Aquatics Flashcards
What should you consider when siting a water element in the garden?
- Electricity (if a pump is required; where will cable go; use qualified electrician)
- Water supply (for topping up)
- Outlet (overflow point)
- Safety (for small children)
- Light (too much you get algae, too little and plants don’t thrive. 4-5hrs is good)
- Terrain (avoid low-lying areas that may be frost pockets)
What are the five categories of aquatic plants?
- Oxygenators
- Floating
- Deepwater
- Marginal
- Bog
Water are oxygenators? And give two examples.
(e.g. Myriophyllum verticillatum and Lagarosiphon major). Totally submerged, help keep clear of algae by competing for nutrients. Essential for fish.
What are floating plants and give two examples?
Floating (e.g. Stratiotes aloides and Trapa natans). Float on surface and cut down the light reaching the water. Be careful not to smother oxygenators.
What are deepwater plants and give two examples?
(e.g. Nymphaea ‘Marliacea Chromatella’ and Aponageton distachyos). Grow rooted in the soil at the base of the pond (30-90cm) Usually decorative and help to reduce algae.
What are marginal plants and give two examples?
(e.g. Iris pseudacorus and Caltha palustris). Plants like to grow in shallow water on the margins of ponds in water 15 to 30cm deep.
What are bog plants and give two examples?
(e.g. Gunnera manicata and Primula japonica). These plants thrive in a moist soil that does not dry out and are the same species that can be grown in very wet soils.
Explain the planting of aquatic plants.
- Usually planted between May and August
- Deep water, submerged and marginals are planted in soil in the bed of the pond or in containers if the pond is artificial
- Containers control the growth of vigorous plants and allow easier division and repositioning
- Aquatic containers have a broad flat base with open meshed sides to reduce stagnation of the growing medium
- The container is lined with hessian and filled with loamy compost that’s free of organic matter and excessive fertiliser (fertiliser causes algae)
- Dress with shingle/gravel/grit and lower into the water.
Explain the principles of planting aquatics in ponds etc?
- About 50% of the water surface should be covered with the foliage of deep water and floating plants to keep the water clear
- If coverage is greater than 70% insufficient light will fill filter through for submerged plants to survive
- Deepwater species like Nymphaea dislike moving water or being splashed (Aponogeton will tolerate a certain amount of water movement).
Explain the maintenance of water features in winter.
- Ensure the water surface remains ice-free, especially if you have fish
- Tidy up bog areas, including lifting/dividing/replanting in suitable weather conditions.
Explain the maintenance of water features in Spring.
- Remove leaves and debris from pond
- restock with new plants
- lift and divide overcrowded plants
- Feed container-planted species with slow release aquatic fertiliser.
Explain the maintenance of water features in summer.
- Removed ead flower heads from marginals and bog plants
- Weed control in bog garden
- Cut back vigorous marginals.
Explain the maintenance of water features in autumn.
- Remove as much dead plant material and organic matter as possible
- Cut back oxygenators and marginals
- Remove non-hardy species for overwintering.
What causes algae and what can be done about it?
- Caused by high nitrate levels in the water and excess sun on the pond
- Can be alleviated by increasing the amount of shade the pond gets (floating aquatics covering 2/3rds)
- Don’t top up with tap water (it’s often high in nitrates)
- Use algaecides.
Name three common problems with water features.
- Algae
- Blanket weed
- Ice.
