Peat is useless, compost polluting, manure unnecessary, fertilisers encourage algae. Maximum plant growth is achieved by spreading 6in(i5cm) of soil over the bottom of the pool, but the eventual result is an uncontrollable tangle of the toughest survivors. Container planting is more satisfactory. Soil will have to be replaced from time to time but much less will be needed. With no soil between containers, wandering roots find no encouragement, and plants are confined to tidy clumps. Fish have less scope for mud-stirring. When the pond needs a Spring clean, containers greatly simplify the job. Containers for marginals should be about 6in(i5cm) deep. On the normal marginal shelf this leaves about 2in(5cm) of water above it which suits the great majority without adjustment. The container should be broad-based for the sake of stability. Different species or cultivars should not be mixed in the same container. One loin by loin by 6in(25cm by 25cm by 15cm) will take two or three plants of most marginal varieties and soon make a bold clump. The same size will suit an Aponogeton, Nymphoides or Orontium; or a water lily from Groups I or II. The largest container offered commercially as a 'lily basket', i2in by i2in by 8in(30cm by 30cm by 20cm) with tapered perforated sides, holds \ bushel (8 quarts or 9I) of soil. From the details of the water lily groups this will be seen to be totally inadequate for the larger water lilies without annual soil changes. To avoid this, larger containers must be found for the bigger water lilies. Almost anything that will not disintegrate in water-or pollute it-will do. Wooden boxes and casks will serve, but plastic tubs and bowls are even better. Perforated sides are unnecessary when the container is wide and shallow, the ideal proportions. The wide range of plastic washing-up bowls will cater for virtually all needs. One i8in (45cm) in diameter and 6in(i5cm) deep holds a generous \ bushel(4 gal or 18I); one 2iin(52.5cm) in diameter and 6in(i5cm) deep contains J bushel (6gal or 27I); and one 24in(6ocm) in diameter and 6in(i5cm) deep holds enough to nourish even a Group VII water lily. The larger the container the longer it will nourish the plant, but remember that containers have to be lifted and a bushel of soil will weigh about a hundredweight (51kg) before it is saturated. While planting is in progress care must be taken to keep plants moist. Oxygenators in particular shrivel rapidly on exposure to sun and wind. They must not be unwrapped until needed and their immersion in the pool must not be delayed a moment longer than necessary. WATERSIDE PLANTS If the pool is a natural one the adjoining soil will contain ample moisture to support the lush summer growth of foliage plants such as Rheum, Rodgersia, Hosta, Carex, Peltiphyllum, and even Gunnera. It can enjoy a flowering succession from April to August by planting only primulas and astilbes, with Iris kaempferi and I. sibirica thrown in for good measure.