02/05/2016
Blanket W**d
Last year Andrew was asked to write a mini series for the Mail Online on Pond Maintenance. Here is the first topic which I hope you find useful. Please contact Andrew if you need any more information or help!
Come back next week to find out how to improve your ponds water quality.
Blanket w**d and green water are a common problem during spring and summer and it thrives where ponds have been created in sunny positions. Plants such as water lilies won’t yet have fully grown so will not be creating any shade. Whilst the sun is the main cause of blanket w**d and green water, excess debris such as rotting leaves, excess fish waste, and fertilizer run-off into the pond can contribute to the problem.
A garden pond is all about getting the correct balance, and to achieve this, the pond needs a good amount of plant life such as marginal plants, water lilies and pond w**d. A good covering is needed i.e. 1/3rd of the surface of the pond, to achieve any significant improvement.
In addition, a pond should be sufficiently deep enough i.e. at least 60-75cm (24-30”) deep in order to prevent water warming rapidly in sunshine which in turn speeds up algae growth. Black pond liners are better than pale liners which tend to reflect heat back into the pond.
A pump and filter with an ultra violet lamp is also important to help with the algae, as well as keeping the pond oxygenated via a waterfall or fountain especially if there are fish in the pond. However if it is a wildlife pond, plants, lilies and w**d are sufficient.
By June/July once the lilies have come out in full and shaded the pond, and the marginal’s and pond w**d have grown, the pond should be clear of blanket w**d. If your pond is situated in a sunny spot, it may be an idea to plant some evergreen shrubs next to the pond to help create some shade.
Blanket w**d can be removed by twirling a cane amongst it and putting it on the side of the pond thus allowing any caught pond life to crawl back into the pond. There are many chemicals which claim to get rid of blanket w**d and green water which can be purchased from a good aquatic centre, however it is suggested that a more natural solution should be tried first.
Pond algae can sometimes be discouraged by floating a mesh bag of barley straw in the pond. About 50g of straw per sq. m of water surface area is ideal. Add the straw in Spring and remove it when it has turned black (usually within 6 months). A liquid barley straw extract is also available.