The Beechgrove Garden 2021 episode 7: In this episode, Brian reviews the success of Beechgrove’s box-hedging alternatives, while he and Mairi also share some topiary tips.
Meanwhile, Calum Clunie continues to let us into the world of show growing as he explains his method for taking his dazzling dahlia cuttings in his Leven allotment. And Beechgrove travels across the Atlantic to the Slate Islands to behold rare blue bamboo, while catching up with the Seil Community Garden, which Beechgrove helped create in 2009. Gardening show that celebrates Scottish horticulture and growing conditions.
The Beechgrove Garden 2021 episode 7
Box (Buxus) is commonly planted in gardens as a clipped, formal plant or hedge, although there are many types available that are ideal for naturalistic planting. While box has been a traditional stalwart in gardens, it is now proving more difficult to grow well due to disease and pests marring their neat appearance.
Box is tolerant of a wide range of soil types, provided there is adequate drainage and it does not dry out completely. A reliably moist soil is especially important if growing in full sun, otherwise the foliage may scorch. Box will tolerate deep shade and is ideal for planting beneath taller trees.
Do not allow young plants to dry out. Check regularly and water to keep the soil moist – but do not allow to become waterlogged, particularly in winter. Once established, apply a general-purpose fertiliser such as Growmore at 70g per sq m (2oz per sq yd) in spring and mulch to a depth of 5cm (2in).
If well cared for, small plants should form a reasonable hedge or, in the case of B. sempervirens ‘Suffruticosa’, parterre within three to five years. Cut back young hedge plants and topiary by up to one-third in May to encourage bushy growth. Further trimming can be carried out between May and August, as required.
Trim mature hedges and topiary in August. It may be worth noting that although box hedging and topiary can be pruned towards the end of May, pruning at this time may leave the new flush of soft growth vulnerable to weather damage such as leaf scorch, the result of late frosts, drying winds or unseasonably hot sun and, additionally, diseases such as box blight. Pruning later, during August when the new growth has hardened off and slowed down should help minimise leaf damage due to weather conditions or disease and the hedge should remain neat through the winter months.
Topiary – The Beechgrove Garden 2021 episode 7
Topiary has been used historically in many different European gardening styles, from early Roman gardens through to modern day. From box balls to yew ‘peacocks’, it is so versatile and striking that many are inspired to create their own piece of living architecture.
Topiary is the art of training plants (typically evergreen shrubs and trees) into intricate or stylized shapes and forms. The term may also be used more loosely to describe a number of garden features that rely on the close clipping and shaping of plants.
With a wide choice of flower shapes and colours, dahlias are unrivalled for giving a showy display from summer into autumn. You can combine them with other late-flowering plants like salvias and grasses to boost late season borders, add dwarf cultivars for colour in summer containers or grow them in rows to give lots of cut flowers for your home.
Height ranges from compact (up to 30cm or 1ft), to stately at 1.5m (5ft) or more. Flowers can be open-centered and daisy-like or form complex 3D structures of tight spheres or jagged ruffles. Colours are diverse too; a spectrum from sedate pastels through to riotous reds and oranges.
Dahlias like free-draining soil in full sun and regular feeding to ensure the best flowering. Tie stems of taller cultivars, especially large-flowered ones, to canes driven into the ground.
Dahlias dislike strong winds and cold, wet soil. They’re not hardy so root tubers will need protecting from sub-zero temperatures in winter.