• Robert Blake

a garden designer’s insights on plant choices


Debbie Carroll, a garden designer for the past 14 years, gave a well presented and interesting talk to the Gardeners’ Club on how to choose plants for your garden. Firstly, on taking on a new garden check the soil type in three areas with a pH kit to establish whether it is acid or alkaline. Also look at what types of plants are already there and how well they are doing. The majority of plants will grow in soil that is neutral or slightly alkaline but some positively prefer limy or chalky soil, including delphiniums, clematis and dianthus. Acid soils contain low quantities of calcium and are preferred by azaleas, camellias, rhododendrons, heathers and pieris.

When choosing a new plant do read the label to ascertain its height and spread, best location and any special conditions; beware if you see the word ‘vigorous’! How many do I plant? Avoid a single plant unless it is providing a focal point, and use oddnumbers (3’s, 5’s etc.) as it will keep the eye moving to find a pattern. Spacing is very important as there must be room for the plant to grow into. If you are worried about leaving bare ground then use a mulch or plant annuals to fill the gaps until the shrub matures. Look for plants to cover all four seasons and don’t forget winter. Hellebores will provide colour from January through to March. Dogwood (Cornus) varieties provide striking bright coral-red or lime green stems in winter but do remember to cut them to the ground each spring. Winter plants should be placed where they can be seen from the kitchen or sitting room window.

There are some rules for choice of colours but these should be balanced against personal preference. Reds and oranges jump forward and draw you towards them, so use them as accents as a few go a long way. Blues tend to recede and make a small garden feel bigger. Whites and pale blues hold their colours in the evening and attractnight flying moths. Don’t forget the many different shades of green foliage. Plants with silvery blue or furry leaves indicate that they will thrive in a dry position.

Think of the shape of plants as arrows e.g. the foxglove is a vertical plant while sedum spectabile is a horizontal one. They can be used to guide the eye towards more interesting things rather than trying, for example, to cover up an eyesore such as a large high wall. Select plants with single flowers where possible as they replicate more native plants and help bees and butterflies. Also introduce some native plants such as cowslips. Ivy survives in dense shade and its flowers in late autumn provide the last source of nectar before winter. The flowers turn into berries in February and are the first food source for birds. It needs to be managed and should be cut back hard after the berries have gone.


Finally, some of Debbie’s favourite plants are Dryopteris (Buckler fern), Rosa ‘Iceberg’ and ‘Deep Secret’, Hydrangea arborescens ‘Limelight’ and Digitalis ‘Silver Fox’.


You can find more ideas and useful resources on garden design on her website.