Day: June 20, 2016

Simon Rickard: Herbaceous borders and perennials for dry climates

Simon gave a brief history of perennial borders in Britain and the subsequent further development of this form of gardening, especially in the United States and Holland. Typically such borders were a feature of grand estates with four or more gardeners, and involved a great deal of work and expertise. They reached the peak of their perfection in early spring. Major requirements:

• 6-8 hours of sun per day
• Beds that are much longer than they are wide
• A width of at least 4 metres, preferably more
• The tallest plants to be ⅔ of the width of the beds
• A backdrop of a hedge or a wall
• Very good soil (as for growing vegetables) with plenty of compost, and mulch which is constantly topped up
• Plenty of water
• Long wet springs, short mild summers and cold winters.

Australian conditions are not suitable for the traditional English herbaceous border, but it is still possible to achieve a full, lush and beautiful garden by avoiding early-spring plants and instead using perennials that flower in late summer and which come from countries with similar climatic conditions to Australia.

• Decide on a ‘look’ and stick to it
• Aim for repeat blocks of the same small number of plants
• Shape and texture are more important than colour
• Make sure all plants will flower at the same time.

Reliable late-summer performers:

• Perovskia (Russian sage)
• Agastache (Humming-bird mint)
• Zauschneria
• Sedum ‘Autumn joy’
• Calmagrostis ‘Karl Foerster’
• Miscanthus (needs a bit more water)
• Anthemis ‘Susan Mitchell’
• Many salvias, especially Salvia nemorosa
• Catmints, especially ‘Walker’s low’ and ‘Six Hills giant’
• Gaillardias
• Origanums
• Penstemons, especially P. serrulatus
• Gauras
• Kniphofias
• Phlomis
• Agapanthus – the sterile types which don’t set seed.
• Mixed borders of perennials, bulbs and shrubs can help to keep the bed interesting through every season. Add in winter-flowering bulbs eg crocuses; shrub roses eg damasks, rugosas, species roses (R. moyesii for hips); shrubs such as yuccas, euonymus, euphorbias, cotinus (coppiced to the ground in early spring), cornus, buddleja.