Five-star plant selection

Percy Thrower looks at the best rock plants for the garden

- Percy Thrower

THERE are many kinds of rock plants with very different characteristics and origins. Some are small herbaceous plants and some are tiny shrubs. Some are genuine mountain plants or ‘alpines’, while others come from lower latitudes, even from the seashore, where they find congenial conditions among the rocks. About the only two things they have in common are their relative smallness and an ability to prosper in places too stony for most other plants.

Both of these characteristics make rock plants of supreme interest to gardeners, and especially those numerous gardeners today who have only tiny plots. No difficulty should be found in growing any of the following, all of which I regard as being of five-star quality. Spring is a good time to plant, preferably using pot-grown plants.

1 Armeria

These are the thrifts, and very thrifty they are with their compact tussocks of tough grassy leaves that enable them to survive in poor dry sandy soils. Best for a rock garden is the sea thrift, Armeria maritima, which is common around the sea coast of Britain. The little globular heads of pink flowers are freely produced from May to July, but are rather a washy colour in some forms. For a deep-rose colour, ‘Vindictive’ has been supreme for several decades.

2 Aethionema

These are miniature shrubs with narrow blue-grey leaves and heads of pink flowers like those of candytuft. Few grow above 15in (38cm) in height and all are so delightful that it is hard to say which is the best. But the two most compact are ‘Warley Rose’, a hybrid of uncertain parentage, and A. pulchellum [A. grandiflorum], a species from Asia Minor. Both enjoy warm sunny places with some lime in the soil and both flower in early summer.