Young plants should be frequently stopped to keep them bushy. Lambs' ears, Stachys byzantina (syn. S. lanata) is one of the most common border perennials and very easy to grow. Where space is limited, the sub-shrub, Tanacetum densum-amanum is exceedingly useful with its slowly spreading mats of white, feathery leaves, and it will even brighten up a sunny corner in the rock garden.ROCK GARDEN PLANTS Many alpines, or plants suitable for growing in rock gardens, can also be found for dry, sunny places in such a garden feature. It is amazing how the houseleek or sempervivums can survive on the roof of a building. To see S. arachnoideum in the wild, clinging on to bare rocks and with the morning dew clinging to its web-like hairs is something to be remembered. Aethionemas are very useful in the rock garden because of their summer flowering and help to extend the flowering period as the bulk of alpines flower earlier in the season. The light pink flowers are set off well against the blue-grey foliage. Others worthy of consideration include Geranium subcaulescens; helianthemums, which are available in a wide range of colours; Phlox douglasii and P. subulata cultivars; Raoulia australis; Saponark ocymoides and Thymus herba-barona and Г. lanuginosus. BULBOUS PLANTS A brief survey of this kind would not be complete without including some bulbs. Allium karataviense is very ornamental, not only for its foliage and cricket-ball sized head of flowers but also for the dried seed heads. The well-known crown imperial, Fritillaria imperialis, is worthy of a place, but beware of the pungent scent from the flowers. Other attractive fritillarias include F. acmopetala, F. persica, F. pontica and F, pyrenaica. Galtonia candicans, which flowers in the summer, is very useful for mixing with low-growing herbaceous plants with its 4ft(i.25m) flower stems carrying numerous drooping white bells. In the autumn Nerine bowdeniiis very attractive and, for spring flowering, there are many crocuses, irises and tulips to choose from. Naturally, there are plenty of other plants suitable for dry, sunny positions, but hopefully those mentioned here will provide you with ideas if such conditions are to be found in your garden.Plants for Pools The essentials for the successful cultivation of ornamental aquatic plants are strong light, adequate soil, and water, static or nearly so, of suitable depth. THE SITE Algae, the simple plants which constitute the major weeds of the water garden (whether as the microscopic single-celled forms that turn the water green, or the filamentous type called silkweed) are encouraged by sunlight. But siting a pool in the shade to avoid these nuisances drastically reduces the flowering potential of the ornamental water plants. The dilemma is resolved by siting the pool where it will get all the sunshine possible and by covering half to two-thirds of the water with foliage which prevents sunlight from penetrating below the surface.