Plectranthus Undemanding but underestimated: John Hoyland rediscovers an adaptable plant that can be dramatic, charming and practical in equal measure
Grown mainly for their often highly scented foliage, these tender plants are wonderful tumbling out of pots and can also add a freshness to densely planted borders
Plants we undervalue in the garden can suddenly capture the imagination when we come across them in the wild. On a visit to South Africa I was charmed by an imposing shrub, three metres tall, covered in graceful, airy, lilac flowers. Our guide told us it was Plectranthus ecklonii. I wrote in my notebook that it was a plant waiting for an enterprising nursery to promote its virtues.
At the time Plectranthus were, for me, as I suspect for many gardeners, a group of undistinguished, workaday foliage plants usually seen in hanging baskets or as unloved houseplants in dentists’ waiting rooms. Fast forward two decades and it is now a group of plants that I prize for their undemanding nature, patterned or polished foliage and elegant flowers. In general, though, for most gardeners Plectranthus remain an undiscovered treasure.
Probably the largest collection in Britain of Plectranthus is at The Salutation in Kent, where the head gardener Steve Edney has become one of the plant’s greatest advocates. Steve grows about 140 forms of the plants and for several years he has been assessing the best forms for containers and for summer bedding.
The most commonly available is Plectranthus argentatus, which has large, velvety, silver-grey-leaves. Like a lot of people, I use it in terracotta pots as a luxurious background to more exuberant summer bedding and colourful tender perennials. It is also planted out each year in an inhospitable corner of a wall and a yew hedge where it thrives in the poor, dry soil and shines through the gloom. I have seen it equally at home in densely planted borders among hardy herbaceous perennials. In the Glyndebourne gardens it is used to stunning effect with heliotropes, where the dark-purple of the heliotrope flowers is reprised in the purple sheen on the stems of the Plectranthus.
Plectranthus species range in size from prostrate forms, just a few centimetres high, to monsters that can reach several metres tall. The low, spreading forms tend to have heart-shaped leaves that are delicately marbled or veined. These will drape over the edges of containers or spread themselves around trees and shrubs to form an attractive ground cover. In the exotic garden at The Salutation, Steve uses P. verticillatus ‘Pink Surprise’ at the base of cannas to help suppress weeds and keep the roots of the canna cool and moist.
Taller forms provide dramatic presence, particularly in late summer and autumn alongside salvias and other tender perennials. My Plectranthus ecklonii reaches 1.5m tall. Its soft flowers are
perfect partners to the almost-black flowers of Salvia guaranitica ‘Black and Blue’, while the dark-stemmed Michaelmas daisy, Symphyotrichum laeve ‘Calliope’, muscles its way through both plants; a triptych on the theme of autumn.
As so often happens with a group of plants, once you start growing Plectranthus you begin to appreciate their qualities and slowly discover how they can enhance your garden. Very soon you will be hooked and want to plant more.
WHERE TO SEE AND BUY • The Salutation Knightrider Street, Sandwich, Kent CT13 9EW. Tel 01304 619919, the-salutation.com/gardens/ • Sampford Shrubs Holbrook Hill, Sampford Peverell, Tiverton, Devon EX16 7EN. Tel 01884 821164, samshrub.co.uk • Shrubland Park Nurseries Maltings Farm, Whatfield Road, Ipswich, Suffolk IP7 6LZ. Tel 01473 657012, shrublandparknurseries.co.uk
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