GARDENING: Brian Kidd on how to keep your pond fresh in a heatwave
We have been plagued with duckweed on the pond's surfaceÂ again this year. This tiny green floating plant is a real nuisance and if not treated completely covers the surface soÂ it's impossible to see the fish.
InÂ the winterÂ we managed to clear the entire surface by lifting out sheets of ice, a cold job but the duckweed was encased in the iceÂ so it was removed and plonked straight inÂ the compost bin '“ great.
ButÂ if just one little piece is left behindÂ the weed breeds like mad and in spring we were back where we started.
Off to the garden centre to see if there was a product to do the job. There was. We followed the instructions ensuringÂ none landed on other plants' leaves, so we carried out the treatment before water lily leaves appeared, and waited with bated breath. It didn't work. Back to the drawing board.
We now have a team effort combating this problem. David, our grandson, uses the hose and squirts water over the pond's surface whileÂ I stand onÂ the opposite sideÂ using a fine fishing net to scoop up the duckweed. Previously I have just used the net to scoop up the weed but using the hose meansÂ we remove far more duckweed in a shorter period of time. Why didn't we doÂ this before?
We had another problem aggravated by theÂ hot spell in late June '“ blanket weed. ThisÂ grew so rapidly I was worried the pond water would overheat or the water would lack oxygen so decided to use the barley straw method of controlling it. First of all the worst of the weed was removed, about half a barrowload '“ it is a large pond. This was done using a rake and a lot of oxygenating plants were removed at the same time. But we could see the fish again.
Instead of using barley straw floating mats, we used a productÂ '“Â Pond Clear '“ which contains bacteria found in barely straw. It's expensiveÂ so we bought the largest size as it may need another treatment. It worked. AÂ lot of theÂ weed turned yellow and floated on top of the water and was again removed with a rake. That which clungÂ to the pond's sides simply turned black andÂ disappeared.
We'veÂ had regular visits from a heron which has the cheek to sit on top of the hedge overlooking the pond, eyeingÂ up the fish. ItÂ swoops down and gobbles them up. We were angeredÂ by this and decided to buy a plastic heronÂ to keep real onesÂ away.Â Ours didn't. The heron came down and triedÂ to mate withÂ the plastic one!
So weÂ bought an electric fence to go around the pond's edge, turned it on and watched. The heron arrived, walked up to the pond, got a shock and flew off. A few days laterÂ it returnedÂ and instead of walking across the grass to get a shock, he landed on a large area of water lilies to grab the fish.
The pond is now covered with wooden frames and wire mesh. It spoils the lookÂ but at least the heron can't go fishing. ButÂ when we want to skim off the duck weed, all the frames have to be removed from the pond. Another job we couldÂ do without.
THIS WEEK'S TOP TIP
Plant nerine, amaryllis and colchicum bulbs. Choose a spotÂ where they can bask in the sunÂ and they'll give much autumnal pleasure. They may not be at garden centres yet, butÂ I mentionÂ it now asÂ they'reÂ snappedÂ up quickly.