Pond Care
To help keep the water clear and healthy it is important to develop a balance of plants within the pond.
Mid-spring through to early summer is the best time to purchase new plants. At this time the water is warming up and plants should start to grow away rapidly. In smaller ponds, aquatic plants benefit from being grown in containers as this prevents them becoming too large or invasive. Compost suitable for planting aquatic plants should be a medium to heavy loam.
Plants play an important role in keeping a balanced pool free of algae in summer. Floating plants reduce the amount of sunlight penetrating the water and keep the water cooler, discouraging algae. Introduce free-floating aquatics to the pool by placing gently on the water surface. Aim to keep around 50% of the surface clear of vegetation, if necessary by thinning occasionally during the summer.
Deep-water aquatics with floating leaves such as waterlilies benefit from regular dividing and re-potting because of their vigour. Place containers on raised bricks lowered in stages as their leaves reach the surface, until the appropriate depth is reached. When not being potted on, waterlilies benefit from a supplementary feed in the spring of a specialist aquatic food to encourage better flowering.
Marginal plants are valuable for shading pool margins where algae may otherwise multiply in the warm, shallow water.
Submerged oxygenating plants are vital to pool hygiene and balance. They can be purchased as bunches which can be planted into baskets to keep them in control anchored firmly in place. Approximately four to five bunches, with three to four stems, per square metre of water surface should be sufficient. Plants respire at night in hot humid weather releasing carbon dioxide and depleting oxygen levels which can cause fish to die. Thin out excessive growth and avoid invasive species such as Myriophyllum aquaticum.
Avoid overpopulating the pool with fish. Run a fountain on hot humid nights or play water over the surface of the pool from a hose to improve oxygenation.
Throughout the summer monitor water levels and top up regularly when necessary. Tap water will contain mineral salts and may lead to an algal bloom.
Start removing dead leaves and debris from plants early in the autumn to avoid decomposing vegetation building up in the pond.