Whatever their colour, size or shape, evergreens work year-round.
It was love at first sight. Meandering around The Briar Patch Farm & Nursery in South Berwick, NS, this past spring, I spotted yet another "must-have" plant in Lee and John Dickie's impressive collection of evergreens. It was a small Japanese umbrella pine (Sciadopitys verticillata, top right) and its new growth was a gorgeous golden colour. Of course, I already had a half-dozen evergreen shrubs and trees to plant, and in my head I could hear my long-suffering spouse asking, "Where are you going to plant that?" So I resisted - for the time being.
As the name suggests, trees and shrubs that keep their leaves year-round are known as evergreens, and there are two main types. One is the coniferous species, which have modified leaves known as needles - the pines, spruces, cedars, firs, and others that we know and love. Then there are the broad-leafed evergreens, which have leaves in assorted shapes and sizes, including such plants as rhododendrons, euonymus, some hollies, daphne, box, and pieris. Certain conifers are also deciduous, meaning they drop their needles the way maples do. The most common (and native) example of this in Atlantic Canada is the larch (Larix laricina), known regionally as hatmatack or tamarack; its needles turn gold before dropping in autumn. A lesser-known but beloved personal favourite is the dawn redwood (Metasequoia glyptostroboides), which is coppery-orange in the fall. Tim Amos is a horticulturist and instructor at the Nova Scotia Community College's horticultural trades program in Kentville. His garden has a choice selection of trees and shrubs ranging from a 30-year-old dwarf Buxus (box) the size of a basketball with a three-inch-wide trunk, to an 8-foot tall hedge of gold cedar with a pruned "window" in the middle. He's lyrical about the joys of gardening with evergreens.
"Conifers and other evergreens come in all shapes, sizes and colours," Tim says. "They are the foundation of a good garden, making excellent backdrops for herbaceous plants. They provide shelter from winds, refuge for nesting birds, and create lovely sound as the wind blows through them. Evergreens create visual barriers in gardens that can be developed into 'rooms' and provide a sense of mystery that entices visitors around that next corner. Subtle things like frost or new snow on leaves provide winter interest, while new flushes of growth in the spring provide colourful excitement as they emerge from winter dormancy." People are often deterred from planting conifers by siting and size issues. "It's a real chore to try to fit a large conifer into a small space," Tim says. Doing some research beforehand to determine just how tall and wide a particular plant will grow goes a long way to achieving garden satisfaction.
Visiting other gardens, both public and private, as well as plant nurseries with display gardens, is a great way to develop ideas for adding evergreens to your own garden. Kingsbrae Garden in St. Andrews, NB, has an exquisite display of conifers. Tall, well-groomed cedar hedges provide some shelter from prevailing winter winds as well as creating sections in the garden. The conifers range from mature trees to dwarf specimens of many species, with lovely variations in shape, texture and colour. For people with small gardens, there's good news in that there are so many dwarf evergreen varieties available. The Briar Patch's John and Lee Dickie carry a wide selection of dwarf evergreens. Lee says, "We are always promoting choices like dwarf spruce because there's no maintenance and they're relatively pest- and disease-free." The Dickies have numerous shrubs and trees in their display gardens, which helps many a customer decide on the perfect evergreen.
Once planted, broadleaf and conifer evergreens require little in the way of maintenance. Problems often arise from improper siting, such as planting a conifer in a spot that gets too little sunlight, is too dry or too wet. Most evergreens prefer a soil that is humus-rich and moist but well-drained, so if your soil is on the heavy side, make sure to amend it with plenty of compost or other organic matter. Dig your shrub or tree's hole twice as wide as the size of the plant's root ball, but set the plant into the ground so that it's at the same level as it was in the pot. After planting, mulching helps keep soil moist and shades out weeds while your new evergreen is settling in, and you can top-dress yearly with organic matter before adding more mulch to the base of the plant.
A frequent complaint with evergreens, particularly conifers, is about browning of foliage during the winter. Conifers shed and grow new needles each year, so don't be alarmed if you see older needles, especially on the inner parts of branches, browning and dropping off in late summer or autumn. However, if you see browning and needle loss on the outer edges, the likely culprit is injury or stress. Often the stress is from drought, an issue in parts of the region in recent years. Watering deeply once a week is far more beneficial than a light daily sprinkling. Evergreens lose water through their leaves in winter, just as they do during the rest of the year. If it's a snowless winter, watering every couple of weeks will help keep the foliage from drying out.
Sometimes a disease such as juniper rust or needlecast on spruce can be a problem, but there are treatments; consult a reputable nursery operator for recommendations. Because browning can occur due to wind damage, Lee Dickie stresses the importance of planting broadleaf evergreens and more tender conifers so they're protected from north and west winter winds. "If people want to protect things with a barrier, I suggest cutting evergreen boughs or even whole trees to create a windbreak. I've also recommended Wilt Pruf, especially for pieris and rhododendrons," Lee says. Wilt Pruf is a spray that prevents moisture loss through leaves. "Personally, I don't want to look at burlap, I want to see my evergreens during the winter, so I plant them where wind isn't an issue if I'm concerned about their tenderness." Browning can also be caused by salt damage in the winter, so expect this if you have evergreens near a road. There's not much you can do about road salt, but try to avoid getting salt from your walk or driveway on your evergreens. Likewise, don't shovel snow onto them. And don't place evergreens where snow falling off a roof can land on the plants and break branches.
Some adventurous gardeners grow dwarf and standardized varieties in containers, but these should be insulated over winter if you're planning to leave them outdoors. Roots are not well protected by the pottery, resin or metal of most large containers, and the cold can be fatal. Some gardeners sink their containers into a hole for the winter, but this can be time-consuming and difficult if the container is heavy. Moving container-grown evergreens into an unheated shed where they're protected from wind and temperature fluctuations can also work, but insulating containers is often the easiest route to take.