Authors Posts by Abigail Higgins

Abigail Higgins

Abigail Higgins

—Photo by Susan Safford

Mulch or Cover-crop for Fall

Nighttime chill, holding the threat of frost, triggers changes in our gardens (and in us), prompting the close of the growing year. Experienced gardeners know that preparation for the next gardening year starts well in advance of its arrival. In dry spells, such as the one we have recently experienced, the more moisture-retentive organic matter in the soil, the better the survival and growth for the coming year.

In vegetable gardens, as crops are harvested and cleared, various “green manures” or cover crops may be sown. This is a term describing plants specifically grown to be tilled into the soil, instead of yielding harvestable crops. After protecting the soil surface they are incorporated into the soil; the breakdown of their root systems and green top growth supply the soil organisms with valuable nutrition.

Depending on the season, this might be a warm weather cover crop such as buckwheat, grasses, or legumes. Oats are used later on; they will winterkill but still hold the soil. Winter rye is one of the most commonly used cold weather cover crops; on the Vineyard it usually holds over the winter and resumes growth in spring. Blends are also available, either locally or through seed catalogues, containing mixtures of both legumes and other types of plants.

The aim is that, apart from cool weather crops still in place, the garden is completely covered, either with green, or animal, manure or mulched with organic matter from compost or leaf piles. An over-wintering crop, such as garlic or fall-planted potatoes, also benefits from being mulched.

Cover cropping is usually restricted to vegetable patches and agricultural soils, while mulching is what happens in the ornamental garden or shrub border. The goals are the same, however: to cover the soil surface and protect it from wind and water erosion; and to layer on organic matter that feeds and enhances soil organisms, whose action adds humus.

There is a style of mulching that resembles the application of a “mulch blanket,” which stays there, all season long, for the purpose of suppressing weeds and minimizing maintenance. This differs from the application of mulch that is worked and cultivated, so that it is continuously incorporated and digested by soil organisms.

Gardeners may hear about intricate rotational systems for vegetable gardens, and the green manures specific to the rotation. This is good husbandry but is confusing. Until one has gardened in a specific spot for a number of years and gotten to know it, much of this is guesswork, soil testing notwithstanding. If you adhere to the guideline of getting as much organic matter into the soil as you can, you will be improving it.

Take soil samples for testing now. Go to the UMass soil testing website for information, Other soil testing labs that perform more intensive types of testing do exist; they may be found with an internet search. Be prepared to take the advice that is sent to you with the results, as part of your fall garden work.

Food Garden: Harvesting & Storing

Harvest seeds and herbs for drying, such as dill seed, peppermint, and sage, for use as teas, seasoning, and for seed to sow in the coming year. I cut sprigs and seed heads, tie them in bunches with garden twine, and place them in paper bags to dry. The bags catch whatever shatters, or breaks off. Harvest dry shell beans and finish drying on trays, to be shelled and stored when they rattle in the pod.

Plant garlic in prepared, fertile soil by separating the cloves and planting up to four inches deep and 6-8” apart in rows at least one foot apart. Sow hardy crops that will be grown under reemay or other forms of cover over the course of the winter. Dig and divide rhubarb roots: replant in soil that has been amended with good compost or well-rotted manure. Cut down asparagus tops when yellow and mulch the crowns with compost or well-rotted manure. (Rockweed — not eelgrass — and algae are dynamite if you can harvest some!)

Harvest squash and pumpkins; cure before storing. After frost has blackened tops, dig and cure dahlia roots; label well before storing. Harvest fruit that stores, such as apples and pears; only perfect ones may be stored; process the rest. Fall-bearing raspberries are bountiful; I pick and freeze about a pint each morning before work, by traying them in a single layer in the freezer, and then pouring into zip lock bags. Pull cabbages and store, roots and all, in cellars or other cool, darkened place. Four good-size cabbage heads yield about seven quarts of naturally fermented sauerkraut, which may be stored indefinitely in the fridge.

Ornamental Garden

Cut-downs proceed as perennial plants finish their business. With the dry conditions, cutting down sooner than usual may be helpful to drought-stressed perennial plants. Re-work edges, weed, and cultivate, prior to top dressing with low number organic soil food and capping with mulch.

Here is a timesaving move: certain beds may be dealt with by using a power mower on them, blade set high. It speeds things up considerably. Rake up the resulting debris and compost it, top-dress with fertilizer, and then cover bed with mulch or compost. With cleaned up edges the entire bed looks tidy and well ordered for the coming season.

Peonies and iris, both bearded and Siberian, may be dug, divided, and reset, using compost or leaf mold to enhance the planting hole. (Refrain from fertilizing directly in planting holes.) Likewise, strong growers such as lysimachia, Shasta daisies, phlox, some hostas, and many asters may be cut down, dug, and separated into smaller pieces for replanting. The same goes for an ornamental grass that has become out-of scale for its location. Cut it down, dig the clump, and then divide it using the classic, “two spading forks back to back” to prize the root mass into smaller chunks.

Evergreens, especially the broad-leaved ones, such as rhododendron, pieris, skimmia, and sarcococca, continue to transpire all winter, and lose valuable moisture from their tissues during our up-and-down, freeze/thaw cycles. Newly planted trees and shrubs are at greater risk too. The unusual dryness of this fall is placing additional stress on these plants, since going into winter in a desiccated state is a real killer. Provide supplemental water and spray these plants with an anti-desiccant to help them hold onto critical moisture levels.

"The Brown Turkey." —Photo by Susan Safford

The Living Local Harvest Festival: at the Fairgrounds, West Tisbury!

Last week’s long-awaited rain amounted to 0.85” in my rain gauge. Luckily runoff was minimal, as it was delivered softly, without downpour.

My hens are pretty well molted, so I am cleaning the henhouse and composting the litter, preparatory to its mellowing over the winter in the soil of the vegetable garden. The litter has been building since last fall; its high feather content — protein — is a soil asset.

Figs, best savored unadorned

The growing of figs on Martha’s Vineyard seems to have been uncommon until relatively recently. It’s likely that horticulturalists of years back, such as the late John Perkins of Edgartown, tried them, though. Today, with changes in weather patterns — and Sumner Silverman’s indefatigable distribution of propagating material from the prunings of his several pampered fig trees — numerous Island fig trees now exist.

The common fig, Ficus carica, in the Moraceae, has been cultivated since ancient times, and has many mythological and classical connotations. As a garden plant in mild zones (zone 7 and south), the trees with their iconic foliage provide a bold textural contrast, and prefer to be sited “in moist, well-drained soil” (Michael Dirr) but are adaptable.

I accepted three of Sumner’s prunings and rooted them in water over the winter. Only one actually took well enough to pot on, and that is how I got my “Brown Turkey” fig tree, one of the more reliably hardy varieties for our plant zone.

The temptation to grow figs in-ground is great: Schlepping a potted fig in and out, with ever-increasing root-ball and container sizes, requires just the right sort of situation and a strong back or hand truck. The men in my family had, however, unilaterally decided that their projects required a concrete slab on the best spot for my fledgling fig tree.

As we saw, last winter’s weather proved to be a setback for fig trees planted in-ground by risk-taking Islanders. Many were killed down to the ground. Although most regenerated, some did not, and an entire season’s fruit was lost. It is the fruits (and eating them) that are the main point. The vexing concrete apron inadvertently saved my fig tree, most likely.

Culture of figs has been something of an enigma. Their being such newcomers here means there is no long-standing local tradition, unlike growing, say, apples or peaches. Sketchy information that exists suggests they are more suitable for the South or California.

Stories of the elaborate rituals that elderly ethnic gardeners of Watertown, Charlestown, and the North End of Boston have developed to cosset fig trees in their urban backyards have circulated for years. However, without firsthand knowledge of how to do the trick, it seems risky to attempt severing half the roots and bending over the tree (one reported technique) to bury it in a straw-filled pit!

Plus, figs have quirks that mean that by incorrect pruning, one can prune away the entire future crop. I was happy to acquire the following advice from “Gardening at Longmeadow” (BBC Books, Random House, 2012, 351 pgs.), by Monty Don, the respected British garden authority, and from “The Cook and the Gardener”  (W.W. Norton & Co., Inc., 1999, 632 pgs.), by the chef Amanda Hesser, whose cookbook is based on the gardening year in Burgundy.

I quote at length from Don’s “September” section of the above book, because it supplies the most complete information I have found on understanding fig habits. (The fig trees Don writes about are planted in-ground, in Britain.)

“Figs can produce three crops simultaneously and invariably have two on the go at any moment. At this time of year there will be large ripening figs, half-sized ones and, if you look closely, tiny pea-sized, even pin-head, fruit tucked into a joint between stem and leaf. These tiny ones are next year’s harvest.

“The in-between ones — essentially any that do not ripen by the middle of October — will never ripen in northern Europe although further south they will produce a delicious harvest from New Year to early spring …” He goes on to describe how they sometimes ripen further, but for various reasons never amount to anything.

“The solution is to wait until you have harvested the last ripe fig at the end of October and then remove every single fig bigger than a fingernail. … The fruit are formed towards the tips of healthy young shoots so for a maximum harvest it is best to roughly fan-train the fig against a wall, removing about a quarter of the oldest stems every year along with any growth that is growing out from the wall or crossing. Do this in April. Then in August, prune away any overly vigorous outward growth that will shade the ripening fruit.

Hesser writes in a similar vein: “In a warm climate, figs enjoy a double season like raspberries, only slightly later. The first season usually occurs about midsummer and a second in the fall. Burgundy is on the fringe of fig-growing latitudes, so only the figs from the first session actually ripen enough for consumption. The second-session figs grow halfway then shrivel up, burdened by the bite of frosts.

“The trees remain in this half-developed state through winter … until the trees are pruned in March.”

After I pruned my tree in early April, I was fortunate to be given a mammoth nursery pot for my “Brown Turkey,” at just the point when it had burst its former container and needed greater root room. I replanted with Fort Vee compost and was rewarded, as the photograph shows, with a nice harvest of fruit.

My collection of cookbooks is quite respectable, yet among the whole there are very, very few recipes for fresh figs. Hesser concludes her section on figs with a recipe for an apparently artless confection. She writes, “This is not a sophisticated recipe, as you can see by its length, but the last fruit I would ever want to torture with overcooking would be the fig.” Which goes to show that if you have fresh figs, the best thing to do is just eat them! Convert the surplus to jam.

Sedum ‘Xenox’s’ glowing flowers are set off by its dark foliage; it partially obscures green-leaved S. ‘Matrona’ (behind). —Photo by Susan Safford

These are blue-sky days, great for weddings; but I am a gardener and hoping for rain. Everything I see is hanging in droughty ribbons. Yet “there is no drought, only abnormally dry conditions.”

Early Fall Garden

Gardeners face such a variety and quantity of projects and endeavors at this time of year that it is hard not to be bewildered and spun upon the wheels of indecision.

Redesign? Rework beds? Dig and divide? Renew soil? Prep houseplants to return indoors? Visualize plantings and order bulbs? Soil test? Lawn repair? Mulching? And it isn’t as if we are all ladies and gentlemen of leisure, daintily picking up a pair of garden snips in our endless idle hours!

However, let’s review these topics. The end of the season is a great opportunity to go through the garden with a revising eye, while the recollection of what worked, what did not, and what downright annoyed you, is still fresh. (This is where frequent photos of the garden help greatly.) In my garden, a Japanese maple sapling is coming out — not without guilt on my part. It was part of a scheme of three young trees, planted to create a backdrop with four-season interest for a portion of a bed. Well, this one proved to be more of a light-blocker than I’d anticipated, so — sayonara.

Reworking beds is simplified after plants have been cut back, although the digging can be laborious nonetheless. Removing growth creates clarity vis-à-vis their location and relation to one another, and there are no tops to deal with if you decide to shift some. This is a good opportunity to renew soil by adding compost or leaf mold, too, while plants are out of the ground, especially if you did find the soil hard to dig.

Mulching can be just about the last garden task of the entire year, done after leaf drop and cleanup, and just before true cold weather sets in. Alternatively, should you have had a load of mulch delivered and unloaded in a convenient spot, it can be spread, little by little, as you do this reorganizing work. Keep a bag of low-number, organic soil food (i.e., fertilizer) nearby, to side-dress the area around the plants as you mulch.

You know with certainty that next spring you will find that your place needs more spring-flowering bulbs, so don’t disappoint yourself. Ordering bulbs should be simplified if you have been perusing the bulb catalogues as they come in. Many arrive in spring, while bulb season is underway. The rub is that the lists may be made “mentally” and “mentally” disposed of, too.

With the endemic Island deer problem, where we can plant tulips for any real landscape enjoyment is a problem. For several years I have been locating tulips in my vegetable garden, more as a cut-flower crop than as an enhancement of the garden landscape. This year, however, voles (?) seem to have discovered them; I continue to find dug and gnawed tulip bulbs lying on the ground.

If you wish to have plants such as digitalis, lunaria, hesperis, and lychnis, biennials all, sow or locate the young plantlets and transplant, or let grow, now.

Houseplants have grown over the summer, and may need repotting before returning indoors. Water well and then remove root balls from pots and slice off about an inch of root mass and old soil, using an old kitchen knife. Replace in pots and fill in with fresh container mix. Soak them well. Top growth may need to be reshaped to balance the loss of roots.

Lawn repair and renewal is a classic fall project, but one that is predicated upon the arrival of fall rains. While warm, dry conditions prevail, hold off on this one.

Soil testing may be done now, and no oven drying is needed — the soil is already dry. The new address for UMass soil testing: UMass Soil and Plant Tissue Testing Lab, 203 Paige Laboratory, 161 Holdsworth Way, Amherst, MA  01003. Go to the UMass web site at for information and to download order forms. Specify that you want advice for organic management.

Fall Garden: Sedums

When summer’s annuals and perennials are looking tired, the sedums come along to enliven the garden scenery and attract myriad pollinators. In this dry month, they have been outstanding! Most familiar may be the sturdy, often-used “Autumn Joy” (Hylotelephium “Herbstfreude”), but there is actually much more to choose from among these succulents. Late-summer sedums’ color range is primarily pale pink aging through ruby to mahogany.

If one goes toplantlust.comone can view the many varieties and cultivars of sedum (also called stonecrop) available, and find where to get them. The variety is extensive and enormous, and many are for specialist gardeners. These are all succulents and well adapted to dry or rock-garden conditions, something to keep in mind during these “not drought” times.

My new sedum fave is “Xenox,” a dark-leaved cultivar just under two feet tall, with rosy pink flowers at summer’s end. I like it grouped with “Matrona,” a slightly taller German introduction with paler, starry flower heads that age pink, greenish foliage, and wine-red stems.

The stonecrops as a group are endearingly called “kinder” plants, as leaves and stem pieces root effortlessly, producing offspring, or “kinder.” Give them full sun exposure and well-drained soil, and divide after three or four years. The plants of large-flowered taller varieties may be pinched early in the season to make for bushier growth and daintier flower heads, which may lessen the need for staking a large clump.

Drought stress? Background trees at the Place on the Wayside remain green, while maples have turned red. — Susan Safford

Abigail-HigginsThe Labor Day weekend rain, four tenths of an inch in my rain gauge, could not have been timelier. The flawless weather of the past several weeks was perfect for the Fair and likely drew few complaints from visitors. However, as drought conditions emerged, it was another story for farmers and gardeners. Watering has been doubled up, insufficiencies in irrigation programs revealed, and signs of stress have appeared everywhere, in domesticated and undomesticated landscapes alike.

It is impossible to over-emphasize the importance of composting, mulching, and using composted woodchips to build up soil and offset the detrimental effects of dry spells, as well as other extremes, but now is an apt moment.

A soil scientist could better explain the processes that take place in the breakdown of organic matter into compost and humus, but my own experience satisfies me sufficiently. Microscopic bacteria and fungi are at work, but I do not need to see them. Go out in the early morning and see what is wet with dew. Bare “dirt” is dry. Soil containing lots of organic matter — earthworm casts, leaf mold, compost — is dew-soaked and wet, due to its ability to attract atmospheric moisture out of the air and hold it.

Whatever your yard, lot, or garden generates, in terms of biomass waste, needs to go on a compost pile and be returned to the soil from which it originated.

It is good for your land and it is good for your municipal landfill! The lawn, flowers, or vegetables that are grown with this reinforcement are far more resilient, drought-resistant, floriferous, tasty, or nutritious than they would be without it. Although many of us could care less, it is a personal carbon sink as well.

When you see a tree or shrub with some leaves already turning yellow or red at this time of year, you may sure that you are seeing signs of stress. Drought stress is draining those parts of the plant of their green chlorophyll (which is almost like human blood) and revealing the underlying pigments that the chlorophyll’s presence masks. It is autumn, but prematurely.

Maples, with their shallow root systems, are particularly vulnerable to drought, or to the radiant heating of the soil that takes place at this time of year, but drought stress is not limited to them. Although maples (genus Acer), are the favorite tree of millions of Americans, this is one reason that I do not recommend planting them here. They are beginning to suffer chronically in this plant hardiness zone. Think Canada: the trademark tree of cool, northern, forest conditions is becoming too marginal for 7a.

However, if your maple or other woody plant is turning red in August, mulch the root run area, and then water it. Compost, leaf mold, straw, mulch, composted wood chips: all will moderate the soil temperature around the root system and help to attract and hold in moisture.

Start harvesting

Though the thrum of cicadas is still rattling high in the oak trees, it is time to return to school. The earliness of it is a shock, since it seems as if the last day of school was only just the other week. I am thankful I no longer have to pack school lunches; the situation has become vastly more complicated by allergies and dietary preferences, leaving aside kids’ traditional pickiness. Kristin Kimball of Essex (N.Y.) Farm, the author of The Dirty Life, has some practical suggestions in this post about school lunches on the farm website,

The time of harvest is also here. My husband becomes Mr. Green Bean and takes responsibility for freezing them. He has recently expanded his repertoire to include making and freezing kettles of Garden Special, an indispensible, all-purpose base of tomato, onion, green pepper, and celery (our valuable collection of Mermaid Farm yogurt containers thus finds its ultimate purpose.)

The cellar, with its dehumidifier running anyway, holds trays of drying shell beans and mystery bags and bundles of drying herbs and seed-heads. Strewn around my kitchen counter are trays of halved and seeded paste tomatoes for the purpose of making Tomates confites, a delectable oven-roasted product that may be frozen or preserved in olive oil. (I am re-printing it because it is such a versatile way to preserve tomatoes.) This year I tried putting them in my closed cold-frame to pre-dry before turning on the oven, which becomes a “hot-frame,” achieving 150°F.

Tomates Confites (from Chocolate & Zucchini)

  • Ripe ‘Roma’ or ‘San Marzano’ (paste type) tomatoes
  • Freshly ground pepper, sea salt
  • Chili pepper flakes (optional)
  • Dried herbs, such as rosemary, oregano, thyme (optional)
  • Olive oil

Preheat oven to 210°F. Cut tomatoes in half and ream out seeds with your thumb (save juice and pulp for another purpose). Place cut sides up on a well-oiled or silpat-lined baking sheet. Sprinkle with salt, pepper, spices if using, and drizzle with olive oil. Put into the oven to bake for two or three hours, keeping an eye on them. Use warm or cold in pasta, salads, sandwiches, spreads, soups, etc. To freeze without clumping, freeze the baking sheet for a couple of hours, after which you can transfer the tomatoes to freezer bags or containers.

Oxalogenic trees

Aviram Rozin, in a recent talk at The FARM Institute, described the reforestation work of his organization, Sadhana Forest. In arid, deforested parts of India, Haiti, and Kenya, Sadhana Forest’s projects focus on indigenous reforestation, water conservation, food production, and introduction of sustainable practices. They have enjoyed a high success rate due to practical, low-tech methods of propagation and planting, emphasizing long-term sapling survival above sheer numbers of planted trees.

An enlightening facet of Sadhana Forest’s projects has been the searching out of tree species to plant in each locale that are not only native, having food, fodder, or medicinal properties, but which are also oxalogenic. This is the ability to go beyond sequestering atmospheric carbon, which all trees and forests store in their tissues, to actually transferring it into the surrounding soils, in the form of calcium carbonate, for long-term storage.

Red Mallow. — Susan Safford

Abigail-HigginsThe sun is falling steadily lower in the sky. It signifies not summer’s end, but tells us that it is drawing nigh. This amazing season has given gardeners much to appreciate and be thankful for. The heat waves experienced elsewhere did not materialize, despite predictions, and there have been few Japanese beetles and mosquitoes. Nights have been cool. Rainfall has been sufficient and often at night.

Scene-stealers in the August garden are the hybrid hibiscus now in bloom. Those unfamiliar with the theatrical plants’ dinner-plate sized flowers and stature are literally stopped in their tracks by them. What a floral tour de force!

The question of the August garden has become more perplexing, with height-of-bloom times speeding up almost yearly: stars of high summer such as oriental lilies and some phlox cultivars are almost passé by the beginning of the month. Fortunately, hibiscus hybrids seem to have resisted this speeding-up process, and still reliably take center stage in mid-August.

According to “Herbaceous Perennial Plants,” Allan M. Armitage’s big book of perennials (Stipes Publishing LLC), many of the garden hybrids were bred from Hibiscus moscheutos (“mos-KEW-tas”) a North American native, along with other vigorous members of the genus. Islanders know the beautiful pink stands of them, along our brackish coves and salt ponds, as “marsh mallows.”

Hybrid hibiscus plants share the hardy nature of their wild ancestors and the brilliant colors of their tropical relatives. (Armitage mentions the outstanding work done by the three Fleming brothers of Lincoln, Nebraska, in this hybridizing.) Many are patented plants and not always available in small local nurseries, but finding and growing them is worth the effort for the show they put on. The color range is white through pinks/lavenders to red and beyond red, to an almost black; one, ‘Old Yella,’ is a buttery primrose.

Space them out

The heights of hardy hibiscus hybrids vary from compact to super-sized, but most require plenty of room and air space. Do not try to shoehorn a hardy hibiscus into that small blank space that “just cries out” to be filled. Hardy hibiscus hybrids prefer full sun and fertile, well-drained soil. They appreciate adequate moisture but, unlike our beautiful, Island “marsh mallow,” they do not need to be planted in a swamp! Figure two to three feet wide and about four feet high for spacing most, with some becoming one to two feet taller where happy.

Hibiscus plants are categorized as woody shrubs. They are one of the last perennials to break dormancy and emerge in the spring. In the gardens where we care for them, we leave the woody stems until next year’s growth is well up, to avoid disturbing new shoots by cultivating. These woody stems are sturdy enough to be pressed into service to support the current year’s growth, a sort of built-in, self-grown, staking system.

You may encourage sturdier, bushier growth by pinching hardy hibiscus when the shoots are about six to eight inches tall. They benefit from fertilization, but hold off after the third week of June, or you may encourage vegetative growth at the expense of blossoms. Excessive feeding by Japanese beetles or hibiscus sawfly may indicate plants that are stressed; step up efforts at soil improvement.

Turk’s cap lilies

An emblem of Island roadsides and quiet shaded spots in August, the turk’s cap lilies have shone in recent weeks. While there are some people whose aesthetic prevents them from welcoming these towers of elegant orange into their premises, most of us are enchanted with their bright presence, easiness, ability to reproduce and increase on their own, and general resistance to the red lily beetle. So I am dismayed to see that many — though not all — are suffering from browning and loss of lower leaves. Am hoping to learn the cause of this disfigurement.

In the garden

Check grafted trees and shrubs, such as roses, for suckers originating from below the graft union. If they are not removed, eventually the entire plant will revert to whatever species supplied the rootstock.

Watering is paramount now. The afternoon sun is especially hot. The sun’s wavelength shift towards the infrared causes solid matter to heat up and hold heat differently than when the wavelength is primarily ultraviolet. Pots and garden seedlings may need watering twice daily. Keep plants looking good with a liquid feed.

Lift and divide bearded iris. Choose young, strong sections of rhizome. Trim off foliage and roots by two thirds and one third, respectively, and replant about one foot apart, with rhizome just at soil level.

I have seeded beets, carrots, more zucchini ‘Romanesco,’ Swiss chard, sugar snap peas, radicchio, and Portuguese kale but could have done much more — nothing ventured, nothing gained. Continue to weed and cultivate in vegetable gardens. The uncultivated crust that forms accepts less water, including dew, than cultivated soil does. Reemay over my three seeded rows of carrots will, I hope, hold in the moisture the seedlings need to grow well and keep out the bunny that has wormed its way through my fencing.

Parts of well-established clematis vines have succumbed to clematis wilt in my garden, and in others too. It is always a disappointment: to go for years without wilt, and then, in an otherwise satisfying season, to have it appear — “for no good reason,” as we always say. (Well, there is a reason, probably, but it’s not apparent to the gardener.)

If there are empty spots in your vegetable garden, or if you are clearing it out preparatory to departure, mulch them or sow with a green manure (cover crop) of some sort. If nothing else, it occupies the space and prevents the blown-in seeds of weeds becoming established.

— Susan Safford

A late July trip to the mountains of Colorado left me envious of the bright light and clear air and how those conditions enable irrigated flowering plants to hold up and persist in bloom, without succumbing to the mildews and bacteria of our sea-level, maritime humidity. In Vail, we saw overflowing pots of seemingly un-groomed, perfect petunias, full trusses of delphinium and flourishing pansies. For us here on the Vineyard those are difficult accomplishments indeed…although we do have great beaches and the sea.

The high point of Island summer, the annual Fair of the Martha’s Vineyard Agricultural Society, is a few short weeks away, August 21-24. I hope you have been thinking of your entries and planning accordingly. Inform your well-meaning house guests and family members who want to pick which vegetables and fruits are intended as entries!

Due to unforeseen circumstances the 2014 Fair book will not be available online until August 10; apologies for the inconvenience. Fair books are available for pickup at Agricultural Hall and all local libraries.

After the Fair, an unwelcome thought: Labor Day comes, summer’s end nears, and soon the season changes. In gardens the emphasis shifts from summery flowers to berries, fruits, and deepening colors of foliage.

Will your summer-focused garden become a blank non-event? Perhaps there is still time to plant late-flowering perennials and fall-color shrubs, such as anemone, tricyrtis, lespedeza, and witch hazel, to add seasonal interest. Several small trees are known for their high autumn color: Japanese maples, parrotia, aronia, dogwoods, and amelanchier species and cultivars. Ornamental grasses come into their own, flowering, often dramatically, as well as changing from green to eye-catching tan, pink, or reddish hues.

Plan for next fall

Although this fall it is not possible to enjoy any last minute fall-blooming bulbs through planting, they may be planned for. Think colchicums, autumn croci, sternbergias, and more, for autumn 2015. The catalogues are arriving daily.

Speaking of gardens becoming a blank, will your garden be a blank, or a haven, for migratory birds preparing for their long journeys south? As members of Audubon Societies and Ducks Unlimited know well, yearly reports document the relentless reductions of numbers of migratory birds and waterfowl.

I often feel the frustration of powerlessness to change these grim outcomes, which are the result of multiple forces far beyond the control of most individuals. We can, however, think about our investments, consumption, and personal habits.

When I observe catbirds and sparrows hopping down the rows in my vegetable garden, I do not believe they are admiring my planting techniques. It is insect protein they are after. Gardeners need birds, and many deduce the connection instinctively: “What I can do individually is to make my place as hospitable to anything flying by as I can make it.”

We all can do something — permit some pokeweed or wild cherry grow in a back corner, maintain a clean birdbath and feeders, plant a crabapple — to attract and embrace migratory or year-round bird populations. Leave brushy and woodsy areas. Make your place attractive with food and shelter and — who knows — maybe some birds will stay around to work for you!

In the garden

Pretty cabbage whites are fluttering about. Although this European butterfly is a delightful creature, its larvae are the damaging green cabbage worms found on brassicas. Weekly applications of Bacillus thuringiensis (Bt, “caterpillar killer”) sprays on kale, cabbage, broccoli, collards, and more, are a necessity in my garden. Bt is also useful against tomato hornworm, or any other lepidopteran caterpillar. It does not work on beetles, wasps, sawflies, or insects of orders other than Lepidoptera.

Weeds may surge in the hot weather of early August. Many would-be gardeners are really frightened of weeds and weediness, to the point of garden phobia. I used to suffer from anxiety about weeds, but overcame that some time ago. I have several good tools to assist in cultivation, but the weed problem in general diminished when I stopped asking my husband to turn the garden mechanically with the Troy-Bilt. When we stopped turning over the soil, we stopped bringing the stored seed bank to the surface where it could germinate.

The Troy-Bilt tiller, I hasten to add, is a wonderful machine, just perfect for tending two hundred foot long rows in a large truck patch. For a small home garden, 50 feet square, it is way more than needed.

Now, I mainly use the broadfork to aerate the soil, and surface cultivating tools, such as the push-pull stirrup hoe, to weed the rows. Getting enough organic matter into the soil to make it friable and workable is what results in easy-to-manage garden soil. (Sections of this garden are still less workable than others.) Anyone can do this. Just work whatever you have, composted or otherwise, into the soil in the course of the garden year. Once your soil becomes easy to work, weed anxiety will lessen.

Onion time?

Onions are ready to harvest when their tops go over. Pull and lay out in the sun to cure for a day or two, before bringing them under cover to dry and cure further. The necks want to be dry and thin; use promptly any that have noticeably thicker necks — these will probably not store well.

Be on the lookout for squash vine borer on all plants of squash and pumpkin. The lepidopteran insects are susceptible to Bt, but their habits make its use ineffective on them.

Due to August’s heat and sun wavelength, keep a sharp eye on recently planted material and containers. They dry out far more quickly now. Both can be mulched with layers of moisture-retaining material, but these will also harbor earwigs, centipedes, and other insect life you’d just as soon not encourage.

As soon as a crop appears to slow down or be on the way out, get rid of it. Have a replacement crop ready to plant in its place.

Garden stakes must withstand downpours and summer storms. Here, homegrown bamboo stakes support three different varieties of pole beans. — Photo by Susan Safford

As the season wears on and plants grow taller, thunderstorms producing drenching rain such as that of July 16 (not to mention tropical storms) test staking skills and put them in the spotlight. Usually it is only when a plant has flowers or fruit that this becomes a problem, because those are what catch and hold wind and water. Leaves seem designed mainly to shed it.

Garden plants are not turkeys and do not need trussing. The goals of staking: to support the plant or stem; to be unobtrusive; and to be easily adjusted while the gardener is bent into awkward positions. However, stakes are ideally placed earlier in the season so that the plants grow around and conceal them.

Moreover, a stem incorrectly staked is almost guaranteed to break, at the point of support. When staking a single stem, the delphinium being the classic example, the goal is loosely tying in at a minimum of three points; usually the stem is given freedom to move slightly within the twine. Large knots, twine wound heavily around stakes, and strapping-in the plants unnaturally: all are unsightly and to be avoided.

Some plants’ habits require creating a network of twine running through the center for support, similar to slices of a pie. This type of support is needed for Hydrangea ‘Annabelle,’ with many large flower heads produced all over the large plant clumps.

Early pinching or cutting of many perennials may make them bushy enough to stand on their own. This works well for clumps of phlox, but improve airflow by selectively thinning out some stalks too.

Although I use peony rings and wire mesh rings because I have them (bought years ago, when it seemed like a good idea), in general I find them unsatisfactory and likely to promote breakage unless monitored and adjusted carefully. Garden twine and bamboo stakes of different diameters and lengths are the most versatile support materials.

Phlox mildew control

As the season wears on and plants grow taller, thunderstorms producing drenching rain such as that of July 16 (not to mention tropical storms) test staking skills and put them in the spotlight.
As the season wears on and plants grow taller, thunderstorms producing drenching rain such as that of July 16 (not to mention tropical storms) test staking skills and put them in the spotlight.

In addition to the thinning and pinching of Phlox paniculata mentioned above, a cultural tip comes from the phlox growers at Perennial Pleasures’ website, “If you must spray, we have found that horticultural oil works well as a preventative. This is what we do on our potted phlox, which suffer unavoidably from dry and hot conditions in their black plastic pots. We spray every two weeks with light summer oil, which protects the leaves, and doesn’t wash off easily in the rain. Plus, it makes the leaves nice and shiny.”

Vegetable garden

In the vegetable garden, support/staking is the norm for tomato plants, but pepper and eggplants laden with fruit also appreciate it; without support they may topple in windy or rainy conditions. Make cages of sturdy wire and anchor them with earth staples.

Bushy prunings of woody shrubs, “peas-sticks,” cut a bit shorter than a plant’s eventual height, supply just the right sort of support if you firmly stick them into the ground around the plant’s crown. The spring prunings of a large vitex provided me with more than enough for an entire row of sugar snap peas, and are the right color to become invisible, even in the flower garden.

We tried a new early potato variety, ‘Satina,’ this year. Boy, are they ever smooth and yummy! Our usual, ‘Dark Red Norland,’ is great too; it is likely that all new potatoes are an epiphany, compared to tired old storage spuds.

The early broccoli crop, ‘Blue Wind,’ was good-sized and trouble free, although I lost a few plants to root damage — grubs the likely culprits. In fact, all the early crops — beets, spinach, lettuce, kale, etc. — have been very nice. (One cabbage made almost a full crock of sauerkraut.) After losing those few early broccoli, subsequent ones were planted with a large comfrey leaf buried in the bottom of the planting hole and have grown well and trouble free.

The chilly spring seems to have provided the right growing conditions, after all. Did starting the early crops in trays of compost contribute? All gardeners have to decide the answers to those questions on their own.

Care and maintenance revolve around keeping yield coming, whether it is the food from the vegetable garden or flowers from the cutting garden. Most plants of both are annual in nature: it is their ambition to set seed. This means preemptively removing anything spent or near-spent so that the plants keep on trying. This is done, ideally, on a daily basis and ends up in the freezer, dinner table, or flower vase. Examples are snap beans, peas, leafy herbs such as basil and marjoram, cucumbers, squashes, arugula, zinnias, bachelor’s buttons, cosmos, snapdragons. And many more.

Replant after spring greens with carrots, leeks, and turnips, for example. They make great fall and storage crops but we are not so much interested in them in spring, when we hunger for tender greens and peas. Have seed for another crop of bush beans ready and growing in cells. Radicchio makes a wonderful fall crop, being usable through the winter and into the following spring when properly protected. Plant a row of storage squash such as butternut, delicata, or acorn.

As soon as a crop appears to slow down or be on the way out, do not waste time: get rid of it. Have a replacement crop ready to plant in its place. This is what successional sowing means.

Consider a warm-weather cover crop for spaces that will be empty for a while. The easiest is buckwheat. It germinates and comes up immediately. Let it grow to about a foot tall and flower, and then turn it in. Wait perhaps two weeks before planting in that spot, to allow for decomposition.

Allium. — Photo by Susan Safford

A cardinal flashes across the lawn. The treetops sway and sough despite the stillness, awaiting tropical storm Arthur. They and the lawn seem actively receptive of the raindrops, having been so thirsty; in a season this dry, it is a nice variation on the Glorious Fourth.

Garden sculpture: alliums

Ornamental alliums do not appear extensively in Island gardens, which is a pity since as bulbs they are cold hardy, tolerate average soil, and avoided by deer. They bridge the late spring to early-summer season of bloom between tulips until annuals, lilies, and hemerocallis begin flowering.

Two impressive cultivar/species: the astounding ‘Globemaster,’ tall (three to four feet), purple flower heads to eight inches that last and last, and an astronomical price per bulb; and Allium schubertii (more modestly priced than ‘Globemaster’), an exploding fireworks of a flowering head, starred with lavender florets, that may exceed a foot across. Stems are one to two feet tall.

Ornamental onion.
Ornamental onion.

Even after the color has gone by, the skeletons of the stately flowering heads remain effective architectural presences in the garden. Tulips or lilies, in contrast, become entirely null once past, while the standing heads of alliums provide weeks of subsequent interest.

Alchemilla mollis combines well with alliums, whose foliage has a tendency to yellow and fade before the flowering heads do. The alchemilla, a frothy base of chartreuse and green, masks the yellowing leaves.

In the vegetable garden, leeks in their second year similarly send up towering flower stalks topped with fragrant softball-sized flower heads in white, pink, or mauve that attract pollinators and beneficial wasps by the dozens. As the small black seeds ripen and fall, they may germinate around the parent plant and may be lined out, giving the garden a ready-made supply of “pencil” leeks before fall.

The subject was roses

‘Glorious’ is often used in conjunction with roses, and this June has demonstrated why. It has been a great month for them, due mainly to the plentiful rainfall early on and the cooler-than-average temperatures, it seems.

The plants have benefited greatly, with many of their pests absent or delayed by cool weather and wonderful displays of bloom ensuing. I regret however that Island gardens display so limited a selection of them, when there is so much more “out there” in the roses department.

The comprehensive and instructive DK “Encyclopedia of Roses” (Charles & Brigid Quest-Ritson, DK Publishing, 2011, 448 pgs., $40) has informed me greatly this season. I have spent enjoyable time with it, examining its descriptions, full color photographs, and histories of rose breeders — and just plain daydreaming, too.

The coffee table volume demonstrates the stupendous breadth and variety of roses available for all climates. No one needs to be without a rose or roses because of “black thumbs” or other fears, as the popular Knockout series has shown. At one time, many of the most glorious roses available were bred in a band of warm, dry conditions from the south of France through to Bulgaria and Turkey. Roses flourish in those conditions, which is why many of the most comprehensive U. S. rose collections are located in California.

Rose breeders have sought to rectify that situation by hybridizing with a wide array of rose species, yielding floriferous plants that could flourish in the frigid winters of the American Midwest and Canada and in the British Isles with their dampness, and be resistant to a wide spread of disease organisms.

Along with the breeding of hardy and trouble-free modern roses has come a tendency to grow them on their own roots, a big shift from the heyday of Hybrid Teas, whose fussiness required grafting to an understock to do well in the typical garden. Since breaking the ‘taboo of own-roots,’ the cutting-grown rose has become a reality for you and me! A very complete description of how to do this in a baggy is available at

Look for the following DK titles, all worthwhile additions to the gardener’s reference library, in addition to the “Encyclopedia of Roses. In association with the American Horticultural Society DK publishes: “AHS Encyclopedia of Plants and Flowers;” “AHS A-Z Encyclopedia of Garden Plants;” “AHS Encyclopedia of Gardening;” and “AHS Encyclopedia of Perennials.”

American painted lady larvae

Soon after the Garden Notes that ran on June 26, which contained a short section about Helichrysum petiolare and the American painted lady (Vanessa virginiensis) butterfly larvae, the first nests also appeared. I had written about my eliminating helichrysum when planting containers: its tendency to become a magnet for the bristly, black caterpillar nests “disfigured” it in decorative terms, according to my thinking at the time.

Once I connected the black, bristly caterpillars and their frass — bit of ee-yew factor — with the charming adult butterflies, my thinking about the matter changed and I decided to return to using H. petiolare, at least here at home in my own containers.

After checking with Matt Pelikan, whose always authoritative Wild Side alternates in this space, I learned it is possible that larvae may not successfully mature on H. petiolare. “Interesting to know whether it actually works to raise young all the way to maturity,” he demurred.

Preferred larval food of Vanessa virginiensis is species of the Compositae, especially Anaphalis margaritacea, the pearly everlasting of Island sandplains. Much as when monarch butterflies may be decoyed into laying eggs on the milkweed relative, black swallowwort, with abortive results, many other butterflies must find the correct larval food-plant for their eggs to hatch and grow successfully.

While it might signify personal growth and even enlightenment on my part to promote butterfly larvae at the expense of container aesthetics, it is not yet clear if I am actually helping them.


Goodbye and good rest to Walter Ashley, who extended the useful lives of many a mower and power-saw for home gardeners and landscapers alike.

— Photo by Susan Safford

Welcome to summer, officially begun with the solstice. For gardeners the significance is slightly different from that of, say, the Steamship Authority or the Chamber of Commerce. Now the pinnacle of daylight has passed; for the rest of the year it shifts and slowly declines, the wavelength moving more to infrared, as we circle away from the sun.

What this means for plants in gardens and woodlands is a shift from vegetative growth into one of hardening off, flowering, fruiting and seed formation. (Even for humans it is significant, although not much mentioned or considered, for we too are light-driven.)

Pruning of spring-blooming shrubs now ceases, as, cued by light’s wavelength, plants are shifting over into producing wood and buds for next season’s flowers. Perennial plants such as lilies and hemerocallis are preparing their buds to grow and open, and pinching of perennials, such as asters and phlox, draws to a close.

Encouraging butterflies

Before learning that the black bristled caterpillars were larvae of the gorgeous small orange and brown American painted lady butterfly, I had discontinued using the grey-leaved foliage plant, Helichrysum petiolare (licorice plant), in containers: the felted grey foliage attracted them. Their feeding and cocoons seemed disfiguring. Now however, in my own containers, I am using those plants to encourage American painted ladies.

Caring for pieris

Pieris (also mistakenly called Andromeda), such as P. japonica and P. floribunda, are flowering evergreen shrubs particularly well adapted for use in Island landscapes and gardens because they are avoided by deer. Their hardiness range (zones 4-7) puts them securely at ease here; new growth following flowers is colorful and ornamental in itself; and tidy evergreen foliage makes pieris a good screener and winter-interest plant.

However, about now, the leaves of many pieris may begin to show an unattractive stippling. This is usually the result of either spider mites or lace bugs, and becomes more of a problem in dry spells. Both minute insects do their work by sucking the plant’s juices from the underside of leaves, leaving the plants stressed and far less attractive than they should be.

Control the damage by spraying the undersides of foliage with water or light horticultural oil. However, part of the problem may lie in the siting and culture of the plants. Pieris prefer partially shaded sites and moist soil, high in organic matter; the presence of insect damage may indicate that its needs are not being met. Mulch the root-run away from the trunk with compost, leaf mould, or composted woodchips. Soil organisms will do most of the work of digesting and incorporating the organic matter down into the mineral soil.

In the Garden

I recently received a question about leafhoppers on garden vegetables. Since I have often had to contend with this annoyance, I could sympathize more than I could offer authoritative solutions. I mentioned that leafhoppers are often tended by ant colonies, which generally prefer warm, dry soils for their nests, so possibly the garden was dry or would benefit by stirring the soil by surface cultivating to disrupt the ants’ habitat.

Leafhoppers may be controlled by application of insecticidal soap, which must be done either early or late to avoid foliar burn, but they and the ants will return. As with the advice above, in connection with pieris, that the presence of insect damage may indicate that plants’ needs are not being met, I can only urge soil testing.

Hardneck garlic is scaping, a sign that harvest is near. A week or two after removing the scapes is the time to harvest the bulbs. Carefully dig one to check development: the goal is as much size as possible without the “wrapper” breaking open, which diminishes the bulbs’ keeping qualities.

Take steps to prepare and sow the next crops. I have just added additional spinach ‘Tyee,’ — fingers crossed against heat — Swiss chard, beets, and lettuce seedlings, and have sown zucchini in modules. If growing potatoes, the earlies will leave a spot open after harvest for a follow-on crop. Depending on the rotation you choose, this would ideally be something such as beans or brassicas, but any cool weather crop would be making use of the space opened up.

The long chilly spring was perfect for roses. Give them an inch of water per week to help their performance continue as summer’s heat arrives.

Indian pipes, Monotropa uniflora, are emerging from the woodland floor. They areparasitic according to Wikipedia, more specifically myco-heterotrophs. Their hostsare certain fungi that aremycorrhizal with trees, meaning they ultimately get their energy from photosynthetictrees.

Mulching and self-sowing

Plants that self-sow are a great boon to garden and gardener alike. They provide a supply of free plants, and they often place themselves where they want to be, not where we would have them. That demonstrates something about their cultural preference and siting.

Examples of great self-sowers are Alchemilla mollis, Verbena bonariensis, Lychnis coronaria, Lunaria (silver dollar) species, Digitalis (foxglove) species, and poppies of all sorts, perennials as well as short-lived Iceland and annual California poppies.

A client recently questioned me about the absence of foxgloves in her garden. Digitalis purpurea (garden foxglove) is biennial by nature, meaning that the mature plant ripens and releases seed, then dies. The seeds then germinate into tiny new plants, which in turn bloom at maturity two years (“biennial”) later. In theory there are always more plants in varying life stages maturing somewhere in the garden.

Laying mulch, which is done for several reasons such as winter protection, soil improvement, and weed suppression, interferes with this self-sowing process in the same way it helps suppress weeds. I believe this garden’s lack of foxgloves is due to our having mulched it in the fall for the last two years.

The lesson is easy: be careful where you mulch and cultivate if you desire more self-sowers.

The lemony fragrance of some and extraordinary and subtle colors combinations can have the effect of enhancing other flowering plants.

Unknown cultivar's vivid blue flower demonstrates the Siberian irises' appeal in the perennial garden. — Photo by Susan Safford

Abigail-HigginsAbigail Higgins has been writing Garden Notes since 2002, and she has kept a kitchen garden for about 50 years. A resident of West Tisbury, she is an officer of the M.V. Agricultural Society.

Last week’s rain settled some of the pollen-storm surrounding us, for which we are grateful. The sources are at this time primarily grasses, oak, and autumn olive. I report (with relief) the many bumblebees, along with their accustomed buzzing, foraging on the large roseum elegans rhododendrons at my place, primarily at dawn and dusk. Those vast mountains of magenta blossom, usually hosting scores of industrious bumblebees, had seemed eerily silent for the past two seasons.

What’s new in garden irises?        

Colorful spring garden, poppies, iris, and more.
Colorful spring garden, poppies, iris, and more.

The June parade of iris has begun. Actually, dwarf bearded and rock-garden iris, such as the reticulatas, arrived in April and May, providing a welcome early shot of color.

As stand-alone clumps, there are few garden plants that provide the architecture and color of irises. They are a family that sneakily becomes an obsession, due also in part to the lemony fragrance of some and extraordinary and subtle colors combinations, which can have the effect of enhancing other flowering plants.

While the dedicated breeders of all types post their efforts on blogs and facebook pages, where many photos may be found, it is the tall bearded (TB) iris that dominates gardens now. Schreiner’s Iris Gardens is one of the premier American growers; their 2014 introductions may be seen at

Considering the wealth and variety of plants that are not TBs, it is a shame that the selection offered in common trade is so limited. The different types of bearded irises were originally hybridized from different species, according to Renée Fraser on the American Iris Society’s Facebook page:

“The ones that are not TB are collectively known as ‘median irises‘. They are further broken down into Miniature Dwarf Bearded (MDB), Intermediate Bearded (IB), Miniature Tall Bearded (MTB) and Standard Dwarf Bearded (SDB) irises.  Information about cultural requirements can be foundhere.”

The beardless Siberian irises and ‘medians’ have become more interesting to me. Due to drenching rains that frequently coincide with iris season, I find myself searching out cultivars with less height and flower size; originally though, notions of “bigger-is-better” had corralled me. The phenomenal branching and enormous, upward-facing flower of modern TB hybrids require a stem so stout (to withstand toppling in rain) as to skew the plants’ aesthetic proportions.

Siberians are probably the best irises for the perennial border and landscaping. Ensata Gardens in Michigan is the source of many (plus numerous Japanese, Louisiana, and more). From Ensata’s website,, with many Siberian cultivars plus photos: “They [Siberians] prefer a slightly acid, organic rich damp soil, but are very adaptable. Their foliage is tall and graceful all season, even as they turn a handsome red-brown after frost. They are dug and divided in Spring, right after bloom, or early fall. Keep them moist for the rest of the year after transplanting.”

“Coffee For Roses”

Coffee for Roses_book.jpgC.L. Fornari’s new, delightfully no-nonsense book, “Coffee For Roses,” (St. Lynn’s Press, 2014, 146 pgs.) is the book I would have wanted to write if I were as competent and experienced — not to mention as fine a photographer — as C.L., the Garden Lady of Cape Cod and beyond. She is, as well, the author of the beautiful “A Garden Lover’s Martha’s Vineyard” (Commonwealth Editions, 2008, 132 pgs.).

The new book’s subtitle, “and 70 Other Misleading Myths About Backyard Gardening,” says it all: it is an argument-settler. It is beautifully illustrated, mostly with C. L.’s own photography, and affably serves up information on how you should be gardening. Fornari succinctly lays many rumored garden quick-fixes and practices to rest in the 70 numbered, easy-to-digest sections. They reflect not only some of the latest, science-based findings but also some of the older, sturdy 19th century practices that have recently been proven correct.

For instance, number 18: “the soil in vegetable gardens needs to be turned every year.” Fornari’s easy to find “thumbnail” conclusions are featured in boxes; number 18 says, “Turning soil always exposes weed seeds to light, triggering their germination.” Then, the text supplies further information.

Number 51: “I need to do something before this spreads.” The box: “There are several arguments for pausing before taking action.” Then, further elaboration. It is a good format and one that will be very helpful to gardeners wanting to get on with the What and the How, without necessarily attending a master gardener class. (Great hostess gift too, I might mention.)

Earthworms: invasive?

Speaking of gardening myths, a confounding article in the spring/summer 2014 edition of the New England Wild Flower Society’s journal is titled “The Trouble with Earthworms.” Whoa! you say, but yes indeed, earthworms as we know them, those turners of the soil and engines of enrichment, are actually invasive species. For forests, especially, they can be detrimental.

For most gardeners this is news, proudly focused as we are on adding humus and increasing organic content, and considering earthworms as our unpaid helper/allies. “Earthworms from Asia and Europe were introduced to this country both inadvertently, in soil-containing materials, and deliberately, for use in waste management.” Due primarily to their predilection for digesting the debris of the forest floor, the duff layer, earthworms speed up biological activity.

In ecosystems that develop without earthworms, such as in post-glacier North America forests, the biological activity is slow, and is primarily fungal. The duff layers overlaying the soil become the matrix for the plant communities that comprise those forests.

With earthworms now digesting the duff at a phenomenal rate, the matrix no longer supports the germination and regeneration of forest trees. Researchers in Vermont and Minnesota have shown that heavily invaded sites favor certain plant species, including many invasive plant species. “However helpful they are in gardens, in northern forests earthworms are as destructive as white-tailed deer.”