A dry summer

Being mindful about water and planting accordingly.

Hail and farewell: Late summer’s golden splendor.– Susan Safford

Here we are in September’s golden splendor, contemplating the season’s passing and reviewing the summer during its final weeks. While we hope to regain a measure of peaceful quiet, and life returns to whatever “normal” might be, we shall miss our seasonal adrenaline and visitors.

Goldenrod and grasses are spectacular now; they and other features of the landscape appear to be little affected by the dry conditions. Many domestic plantings, meanwhile, are struggling with them. Anxious reports of beach plum scarcity abound, and yet I continue to see bountiful crops in a number of locations.

Dry season

The crabgrass is bright green; everything else, less so. Many of us have been monitoring the dry conditions as they consolidated into drought while the season wound its way onward. The experts have assured us that there is no reason to worry, that the aquifer is — so far — in good shape. Nevertheless, I witness what I consider to be a profound, astounding mindlessness here about water and water use, and am guilty of it myself.

Maybe it takes having gardening friends or houseguests from the arid West, or California, to remind us to use this most precious resource with care. For a more in-depth look at Island water issues, please check out the Island Blue Pages, a project of the Martha’s Vineyard Shellfish Group at bit.ly/islandbluepages.

But that is straying away from what water means to gardeners.

My household is on a well, and I do not ordinarily irrigate my gardens, vegetable or ornamental, without wondering and worrying about how much the well’s static level has dropped. However, currently I am reluctantly watering a bed of beet seedlings (see below) under Reemay that went in two weekends ago. Without watering they would not survive in these conditions of heat and dryness.

Plantings and gardens will be more satisfactory and satisfying if we adhere to designs and plants that do not require irrigation or intensive water use. Neither does being on town water let you off the hook: As a shared resource it actually demands greater obligation, and consideration of others.

If these cyclic weather patterns continue to trend, we shall need all the trees and shade we can get. Plant for future shade now! Avoid all shallow-rooted trees adapted for moist soils (unless you are in a bog), and maples, unless it is a species specifically said to be drought-tolerant. Maples struggle in the heat and drought, and really want to move up north, to Canada. Watering a tree or shrub for purposes of establishment is one thing, for its lifetime quite another.

Plants drooping, parched and tattered, are hard to bear. Most good garden and plant books contain lists in the appendices for different requirements, including drought tolerance. Perhaps the first directory to seek out is the Polly Hill Arboretum Plant Selection Guide: bit.ly/plantselectionguide.

As a general rule, one is looking for trees and shrubs with deep root systems, well adapted to obtaining residual soil moisture during dry periods. Some of these are not exactly noble — more like weed — trees and shrubs. However, among them are a few of my favorites: lacebark elm, zelkova, and catalpa.

Drought stress

Around the Island today, many deciduous trees and shrubs are showing early autumn coloration and yellowing. This is a sign of drought stress in most instances: The plant is looking to shed leaves early, to minimize transpiration of moisture. It is an adaptive advantage of deciduousness.

In my woodland garden, the contrast between planted North American natives Cornus alternifolia and oakleaf hydrangeas, looking sere and parched, and nearby, naturally occurring beech and sassafras, looking green and perky, is quite striking. If your tree or shrub is suffering, deepening and widening the mulch ring with a composted product is one solution to try (keep mulch away from trunks).

Describing the carbon cycle is a few words more than I have room for in my column, but a shorthand way to say it is: Carbon loves water loves carbon. The “brown” of compost attracts H2O. If you are a soil geek, exciting reading about the carbon cycle is found in Kristin Ohlson’s “The Soil Will Save Us.”

For instance, instead of planting mophead hydrangea or clethra, try the deeper-rooted panicle types, or the drought-tolerant natives, bayberry and members of the viburnum or witch hazel tribe. Huckleberry, dangleberry, lowbush blueberry, and bearberry predominate in the understory in several dry-woodland Island habitats; try them for a mass planting.

As an example of a reasonably successful garden for drought conditions in a very hot, punishing Island location, an unirrigated bed contains perovskia, salvia, nepeta, lavender, hardy plumbago (ceratostigma), elsholtzia, and muhly grass (muhlenbergia), enlivened with a few six-packs of annual portulaca.

This planting is nothing complicated or sophisticated — no structured “plant community” here — but has survived well all season with no additional watering, only dew and rainfall. Had the owners decided they wanted an “English garden,” they would have been doomed to failed plants, higher well stress, and disappointment.

Beet seedlings

Trying to work down my seed-packet accumulation, without high expectations I sowed two past-expiration date packets of beet seed in flats of seed mix. In the perverse manner of these things, it appeared that each packet, from 2011 and 2012, achieved close to 100 percent germination. So there I was, with many, many little beet seedlings, growing their first true leaves, to transplant.

Luckily my sister-in-law, who likes to keep busy, was in the neighborhood. She was up for the challenge. On a sweltering morning, troweling out careful handfuls, we dropped them into holes made using the five-prong broadfork as a jig, and “washed” them in with the watering can spiked with comfrey tea. Before long we had a flat and three-quarters planted, all the space available. Under the Reemay they went, and now, delightfully, are accompanied by a seedling catch of lettuce and radicchio, self-sown from the bed’s previous occupants.