I have been gardening in different types of shade for years, and love it. I grow around 600 varieties of perennials, including some of the many fabulous native plants of our Canadian woodlands. Shade creates a cool oasis in which I enjoy the dog days of summer. So it is beyond my comprehension why so many gardeners harbour a belief that gardening in shade is counter-productive.
Shade gardening is no more difficult or unrewarding than any other type of gardening, as long as you practise certain basic techniques. However, trying to understand the numerous terms used to define types of shade is a challenge. Although certain plants, particularly some alpines, have highly specialized habitat requirements, most are not that finicky. After 54 years of gardening, I believe the over-classification of shade creates unnecessary confusion. I simply dump all shade-loving plants into three basic categories: deep shade, half shade and dappled shade. The terms “damp shade” and “dry shade” refer to the moisture content of the soil, not the type of shade itself.
What, for instance, is the difference between light shade, part shade, part sun, filtered shade and dappled shade? From a practical point of view, nothing. All those terms mean that plants require (or receive) modified light-not strong sunlight-throughout the whole day, usually by being planted near or under trees or shrubs.
Then there are the terms “full shade”, “deep shade” and “complete shade”. Once again, they all mean about the same thing, referring to the type of shade found beneath some conifers, a dense-leafed deciduous tree, such as a beech, the north side of a tall wall or wherever plants get little sun. Of course, the more intense the shade, the less plants will grow-and there is shade so dense that nothing will survive. Shade caused by a tree can sometimes be remedied by the judicious pruning of lower branches or, if necessary, the removal of higher limbs (it is wise to employ a professional for this). If you are lucky, the latter solution may create what is called “high shade”-very useful but basically the same as part shade, dappled shade and so forth.
Not all shade, of course, is created by mature trees, but can originate from buildings, fences and trellises. Indeed, fences and trellises are a quick way to make shade if you have none and are waiting for newly planted trees to grow.
And what about the term “half shade”? When used to describe a plant's needs, it means that the plant will do best in-or can withstand-sunlight for just half a day. For example, there are numerous plants, such as hostas, lungworts and primroses, that perform beautifully in morning sun but cannot tolerate the heat of midday or early afternoon. You have likely seen how lungwort (Pulmonaria spp., Zone 4) and Ligularia stenocephala ‘The Rocket' (Zone 4) droop if the hot sun hits them. Conversely, sun-lovers such as black-eyed Susan (Rudbeckia spp.) and purple coneflower (Echinachea spp.) can withstand half shade if it is in the morning.
Yet another time-honoured misconception is that it is useless to try to garden under maple trees. However, gardeners such as myself, who have inherited 50-year-old maples, simply have to make the best of things. The shallow roots of trees such as maple and spruce roam far and wide, grabbing what moisture and nutrients they can find. They also seem to have an extra-sensory knowledge as to where the gardener has recently created a new bed and quickly fill it with fibrous feeder roots. You can fight these roots to some extent with a sharp digging spade, but a better long-term plan is to provide your plants with additional water and nutrients.