Garden Notes : Summer solstice
Solstice once more,
The top of the year:
Mock orange and rose
Mean summer is here.
Nature's air conditioners
Very few are those who can personally recall the qualities and presence of the American chestnut in our public spaces, but many of us are old enough to reflect on the terrible loss the disappearance of the American elm has inflicted on the streetscapes of our towns and cities. Countless photos and references in news, history, and literature portray the cathedral-like quality of their bygone elm-shaded roadways, a quintessentially American atmosphere created by our symbolic American tree, Ulmus americana.
Even in the 1950s, my own childhood, the main thoroughfares of Edgartown, Falmouth, New Bedford, Vineyard Haven, and West Tisbury possessed that inviting, shaded aspect. Today, minus the elms, they present a vastly different feel, often barren and radiating heat, despite the efforts of tree departments and shade tree replacement programs.
Elms continue to hang on here and on the mainland in rural pockets where they are better sequestered from effects of air pollution, asphalt paving, and heat. These are factors that weaken them - and all trees - enough for elm bark beetle, Dutch elm disease, or whatever, to come along and finish them off; but it is we who are killing them.
It's a tough time to be a tree of any kind. More and more species are exhibiting their own particular symptoms of stress in response to changes in environment. Real care for our trees consists not of calling in the tree professional to diagnose or treat, but in sustaining the conditions trees and all living organisms need to thrive.
The first week of June we had a brief taste of the heat-wave conditions less fortunate mainland residents, human and tree, must live with for months at a time; already I have absorbed enough heat-rays to renew my devout gratitude for the shade cast by trees.
Photo by Susan Safford
Working in Edgartown with its diverse, beautiful street trees (not to mention many specimens in yards), I particularly admire a number of magnificent lindens, dangling green flowers resembling Elsa Peretti jewelry. The Tilia species provide beautiful form, dense leaf cover, and deep cooling shade - what magnificent companions to town life.
I recall several striking landscapes with lindens in my own life: the Creek Club's splendid linden allée near where we lived in Lattingtown, on Long Island; and my mother-in-law's in Royal Oak, Md., where many mature old lindens of several different kinds surrounded the house and studded the broad lawn. Even in sweltering July, when we were often there, a cooling breeze almost always played in their shade.
So I echo the dismay of a conference speaker last winter who puzzled over the reluctance of American tree professionals to plant lindens. For all their beauty and pluses, it is one lone negative that causes lindens to remain unplanted: the whole tree is a sweet treat to bees and aphids, and the resulting shower of nectar and honeydew gets on cars and awnings and causes sooty mold.
Some dendrologists hypothesize that the nectar and the sooty mold are the linden tree's way of encouraging more micro life in the soil of its root-run, clever self-fertilizing tree. This factor does not seem to have limited in any way the popularity of lindens as street trees in Britain and Europe, and linden honey, the by-product of the bees' love affair with linden flowers, is delicious and sought-after.
At my mother-in-law's, I thought one tree stood out as more beautiful than the rest; a neighbor who claimed to know told me it was Tilia petiolaris, or pendent silver linden. The branches were gracefully pendulous, the leaves on longer stalks (petioles) than is typical, and their undersides silvery. I want one at our place but the objective is frustrated by an already heavily treed property. Eventually a suitable spot will open up.
Watching the growth of large shade trees is the non-activity of a lifetime, but meanwhile we can get "instant gratification" from smaller trees and shrubs, especially if they are blooming ones. Sometimes they are even better at performing certain functions, like screening or fragrance, than a full-size landscape tree.
About ten years ago John Gadowski urged me to plant a fringe tree, Chionanthus virginicus. He had just received a shipment of some particularly nice ones (he said they are hard to propagate), and he hoped they would go to appreciative people who recognized their choiceness. I bought one hoping to plant it at some client garden but ended up using it myself to replace a much mourned, mature Japanese maple that had been brought to its knees by a wilt the previous autumn.
The tree is in full flower just now, covered with its unusual snowy fluff of blossoms, which have a delicious, although faint, scent. It is so beautiful that I hardly ever think of the Japanese maple anymore. It wants to be in full sun for best flowering and where its somewhat spreading habit can be accommodated. The sizeable specimen near the Polly Hill Arboretum entrance overhangs State Road to seize a few extra rays of sunshine. Ours turns a nice yellow in autumn. The fringe tree is native to the SE United States but is hardy to zone 3.
Chionanthus plants are usually multi-stemmed and dioecious (male and female flowers on separate trees). It is said that males have larger flowers. The females produce a bluish fruit; since I have not yet seen any, our plant is probably male. The mid-green foliage is elliptical, four to eight inches long, pointed, and with smooth margins and texture. It contrasts well with the dark green of a large Rhododendron roseum elegans nearby.
If you have not done so already, cut off the curling flowering tips of rocambole garlic.
Weeds are germinating like crazy in the warm soil. I love the push-pull hoe for holding a weed takeover at bay. It can be used with precision: e.g., going down the middle of a double row of celery plants without taking any out. Use a hand cultivator to "mark" around individual plants and locate them visually, and then hoe for the rest.
Replace or replant lost seedlings and plants. Keep up with succession sowings: beets, carrots, lettuce, cilantro, etc. Pinch out axillary growths on tomato vines and tie in to supports where necessary.
Harvest new potatoes when tops flower; harvest mature potatoes when tops die.
Deadhead perennials and cut out stalks of passé plants like irises and poppies; pinch out growing tips until the Solstice (perhaps a little later on asters and chrysanthemums); stake.
Watch roses for sawfly larvae and thrips and control with insecticidal soap.