Solving the dry shade problem

Gillian Vine fights to get things to grow in dry shade. 

Dry shade is the bane of a gardener's life, and it can be a battle to find suitable plants.

Most plants need moist soil and those that don't, such as cacti, demand lots of sunshine.

There are other issues, too. Rhododendrons, for instance, have shallow roots - just try digging a hole near an old bush if you don't believe me - and their hatred of lime further limits what will survive in their shadow.

Viburnums make suitable companions for rhododendrons. Most grow 1m or more, but Viburnum davidii is smaller, at about 75cm, although to get the blue berries, which are mildly toxic, male and female bushes are needed.

Another acid-loving shrub is Pieris japonica, which does well in shade, although this may limit the quantity of flowers. However, new foliage is red, so there will be colour regardless of a lack of light. Smaller varieties to check out are Christmas Cheer and Dorothy Wykoff for pink and white blooms, or white-flowered Sarabande and Purity.

Flaming Silver grows somewhat taller (1.5m) and has variegated foliage.

Most gardeners look for lower-growing plants that will grow under trees or tall shrubs, or in the shadow of a wall or fence. In warmer areas, it's impossible to ignore clivias. These bulbs have good-looking strappy leaves as well as flowers of orange or yellow, and grow under trees with little attention once they are established.

The best of the annuals in my view is honeywort (Cerinthe major). The dull purple flowers and blue-green foliage are a winning combination, while you don't need to save seed: once you've got honeywort, it's likely to pop up every year thereafter.

Honeywort goes well with purple sage, which seems to do better in shade than the green or variegated types.

Some of the euphorbias - especially the green-flowered ones in my experience - don't mind dim light and dry soil. As green goes with everything, they are a useful anchor plant, despite a tendency to spread too enthusiastically.

Hostas are usually grown where their roots stay moist but some, especially smaller-leafed forms, cope well with dry conditions. Trial and error may be needed to find the most suitable.

Rather overlooked are the ferns. Sometimes called hound's tongue, Microsorum pustulatum is a perennial native with glossy green leaves that will burn in strong sun. Probably the most drought-tolerant small fern, it loves the challenge of dry shade.

Geraniums in the G. macrorrhizum group flower for weeks, their light-coloured blooms shining in a dull spot.

For leaf colour, there are various pulmonarias with blotched leaves. Some have white flowers, others a unique mix of pink and blue. Lemon-flowered Sisyrinchium striatum has a variegated form, too.

If easy-care plants are important, Epimedium is a low-maintenance perennial that is best grown in acid soil, so is well-suited to growing under or alongside rhododendrons. There are pink and yellow-flowered forms, the latter tending to be faster to spread, but the main appeal is the heart-shaped leaves that colour up in autumn.

Taller perennials for dry shade include meadow rue (Thalictrum), monkshead (Aconitum napellus), foxgloves, Astilbe, Astrantia and Japanese anemone (Anemone hupehensis var. japonica), although the latter can become invasive.

Finally, if you are planning to revamp an area of dry shade, it is worth making the effort to improve the soil with plenty of compost. Not only will it give the plants a better start in life, but it will also help retain any moisture that does get through.