Garden Notes

To deadhead hydrangeas, cut back to the first pair of fat buds to avoid damaging them. Photos by Mae Deary

Sprucing up

By Abigail Higgins - April 12, 2007

Outside the species bulbs are providing early color around my place. Tufts of tiny yellow trumpet daffodils have forced their way up through the carex sedge on the hillside behind the house. Narcissus 'February Gold,' misnamed in our climate since it never blooms then, is nonetheless a delightful pool of golden yellow at the foot of a white oak. A potful of Siberian squills given to me years ago by my son have become multiple spots of brilliant cobalt all over the place, as they seed and sow themselves, leapfrogging sporadically farther and farther away from the original planting. Emerging rhubarb leaves in the vegetable garden form crumpled mounds, looking like antique textbook engravings of the human brain in red and green.

Meanwhile indoors, seed trays occupy all the space on my heat mat and are using the floor of my sunspace, where I hope they get a touch of radiant energy from the black landscape cloth on the floor. If it is going to be a hot summer, with all this climate change going on, then I am preparing with okra, a heat-lover if there ever was one. I planted 'Heirloom Red' in mid-March. Added to the Garden Special soup base I like to make, it makes great "gumbo" with hardly any effort. I received a complementary packet of 'Tomatoberry' seeds from Johnny's Selected Seeds, that my curiosity would not let me pass up: they have joined a couple of other tomato varieties that I am trying, 'Marmande' and 'German Pink.'

Pruning winter damage.

Peas are on the up and up

Peas, both sweet and vegetable, are growing away and take up a lot of space. My daughter grows hers in the ground beneath long lengths of rabbit wire folded in half lengthwise into tents that sit over the rows, to foil the crows. She is in a completely different climate and part of the country, although bizarrely we pretty much share a hardiness zone. Here we have not only crows but also cut worms. I have grown weary of watching fully germinated rows dwindle down to only a few lonely plants. I want the pea seedlings indoors under cover for as long as possible, and the hens in the garden catching cutworms, as long as possible.

My experiment with the newsprint starter pots is going well, although I have had to add one staple apiece and masking tape on the bottom to make them hold together. My fabricating technique has improved considerably and you might see me rummaging in the post office recycling bins for more newspapers. Onions, salad, and cabbage make up the remainder of the seed trays. I suffer from gridlock, with a backlog of trays currently, as my small Juwel cold frame was violently uprooted in a windstorm a while back and waits for me to get it together once again.

Maintenance, shaping, and containment pruning of roses and shrubs is part of the spring routine. A reminder is that making an undercut, before taking off a larger branch with the pruning saw, is the way to avoid those nasty bark tears down the trunk. Before tackling all the pruning and clean up, edge tools need sharpening, not only for the sake of making good cuts to the plant, but also with the aim of avoiding fatigue to hands and wrists. After watching the good people of Oesco putting on a sharpening demonstration, hard to share in words, at a recent landscaping conference, I found the following web site, which has good illustrated pointers.

This year an unusual amount of winterkill on broad-leaved evergreens is suddenly showing up, especially on leucothoe and hollies of the aquifolium, cornuta/Burford hybrids, and inkberry groups. Some gardeners like to wait a little longer before going in and cleaning up winterkill by pruning out and removing it. They wait to avoid another meteorological event causing more, and also to see where bud-break actually is occurring. I think it is okay now, but I say that a bit nervously, since the weather has been unpredictable. There have been snowfalls in strange places recently. I think this year would be a good one to be tardy in cutting back buddleia, lavender, or other plants needing the protection of their old wood. Do I say that every year?

In the gardens we are trimming up the roses and climbers, deadheading lacecap and mophead hydrangeas, shearing back inkberry, and cutting Montauk daisies (currently Nipponanthemum nipponicum) back almost to the ground. Pruning roses consists of removing canes and branches with signs of weakness or damage: cankers, rodent gnawing, split, shriveled or red-spotted bark, or weak twiggy growth. Remove the outer third of the cane or branch back to a nice strong bud that faces outward, if possible.

New Dawn for the new season

With vigorous climbers, like the many 'New Dawn' roses Island gardeners so love, I often choose an older cane to remove right down to the crown: keeping a new cane coming so that there is never too much build-up of woody old growth. Train the canes by tying in as horizontally as you can, so the laterals sprout perpendicular to the cane and vertical. Side-dress with fertilizer and/or compost at the same time.

Raking out beds is best done before the perennials' tips are long enough to be damaged by the rake. This is one of the best times to weed out onion grass, while the soil is loose and moist. Weeds like chickweed, spitting cress, and dandelion are already off and blooming but are easily dealt with now.

With lacecap and mophead hydrangeas, even if you don't prune, it is still good to clean out the accumulation of debris from the crowns early, while the buds are small. It is always a toss-up between waiting for settled weather, as these plants need the cold protection of old wood, and waiting too long. Then the buds, containing the embryonic first blooms of this season encased between leaves, are knocked off the canes very easily, as one tries to work around the plants.

A friend asked when to fertilize her hydrangeas with ammonium sulphate, in order for them to be blue. To avoid root burn it is better to apply a small amount every few weeks, one half cup for an area ten by ten, than a lot all at once. The plant can only take up ammonium sulphate once soil bacteria have converted it into nitrate. Bacteria only become active when soils warm up, so apply when plants are in active growth.

Clean up clematis vines according to guidelines of the different groupings. Most garden references contain some sort of listing of different large flowered hybrids and clematis species, and their pruning protocols, if you are in need of advice.

The Polly Hill Arboretum hosts bulb specialist Brent Heath on Container Bulb Gardening from 10 am to noon on April 17. Please register in advance by calling 508-693-9426.