Over the Columbus Day weekend we sat out on our friends’ patio in the golden sunset before going indoors for a wonderful supper. As we admired the fields and the pond our friends told us they had decided to build a pergola over the patio, much as we had, to provide cooling shade on hot summer afternoons. The question was, what should they plant to provide that shade?
We have a wisteria growing on our pergola (which some call an arbor). It got off to a very slow start, but now grows vigorously and it sometimes produces those beautiful and graceful wisteria blooms. While Chinese and Japanese wisteria like mine are not really invasive in our climate, they are strong growers and do send runners out which I cut back when they appear. That is not a difficult chore.
There is a native American variety, Wisteria frutescens, which grows less aggressively, and produces small flowers, however, many find its fragrance objectionable. This is only sometimes mentioned in nursery catalogs.
Our friends have already decided they are not interested in any type of wisteria. We do have another vine that might suit, Actinidia arguta or hardy kiwi. I planted this vine against our tractor shed after seeing its unusual pink, white and green foliage on a trellis in the serene Lakewold garden in Washington state many years ago. Hardy kiwi is a plant that is dioecious, which is to say you need male and female plants to produce fruit. Since I was not interested in the fruit, only the beautiful foliage, I did not have to worry about getting a pair. One vine has covered the shed wall.
If our friends want to add another fruit crop to their garden they could plant grapevines on their pergola. Miller Nursery in Canandaigua, New York offers a wide array of grapes that are hardy in our climate. When I checked their catalog recently they are still promoting Canadice grapes as among the best reds. Canadice is hardy, seedless with a tender skins that begins ripening in mid-August and can be harvested well into September. A sweet grape-y flavor is promised.
Canadice is as hardy as Concord grapes, and I can tell you we have Concord grapes that were here when we bought our house and they are still growing and producing without care. I am sure all grapes produce more heavily if they are properly pruned and trellised, but I know that even grapes grown on a pergola will produce. Miller offers a large selection.
Virginia creeper or Parthenocissus quinquefolia is a familiar native vine with palmate compound leaves consisting of five toothed leaflets. Clusters of small greenish flowers appear in the spring, and are not notable, however the result is a crop of berries in the fall that while not edible for us, attract hungry birds.
The vine has tendrils tipped with an adhesive pad which makes it an excellent climber, but it is best to keep it from latching on to house walls. In the fall the foliage takes on a brilliant red hue which is one reason so many people like it.
My husband recommended Dutchman’s Pipe vine, or Aristolochia tomentosa. This native vine with its large flat leaves can quickly create a very shady wall. It got its name from the flower’s resemblance to the meerschaum pipes smoked by early Dutch settlers in New York. However, the flowers are not very noticeable, hidden as they are among the large leaves, nor is there attractive autumn color.
In New York City Dutchman’s Pipe climbed high up our fire escape, and I have seen it providing a privacy screen on front porches in Greenfield.
One of the special benefits of this vine is that it provides larval food for the beautiful swallowtail butterflies.
If our friends decide they do want colorful flowers they might think about Lonicera sempervirens or trumpet honeysuckle. This is one of the smaller native vines, reaching only a height of about 15 feet. It produces clusters of tubular pink to red blossoms that are not fragrant, but they are particularly attractive to hummingbirds. The berries that appear in the fall will attract other birds as well.
The trumpet honeysuckle begins to bloom in July. Since it blooms on last year’s stems (old wood) it should be pruned right after blooming.
Finally there is Celastrus scandens, the American bittersweet and it must not to be confused with the oriental bittersweet which is such a scourge along our local highways. However, it does produce ornamental berries that are useful in flower arrangements and useful in attracting those hungry birds.
Like the hardy kiwi, American bittersweet is dioecious. It needs male and female plants to fruit. Unlike the hardy kiwi or holly, not all nurseries include the sex of the plant. Gurney’s is one catalog that does promise to send two plants, male and female, to insure good fruiting. Pruning should be done in the fall, although a well established plant will rarely need anything more than cutting out dead or damaged branches.
All of the vines I have mentioned are strong growers. They do not need anything more than ordinary garden soil. A lean soil will help to control growth. They all do need a sunny location, where they can provide you with that desired shade.
Between the Rows October 15, 2011