I have a number of very young water lily plants in three-inch pots, in
plastic buckets, which I am growing-on to sell at our horticultural society
plant sale in May, to help our funds. However, the bright sunlight has
encouraged a lovely crop of prize-winning blanket weed and, obviously, no
one will buy them like that.

I had this trouble at the end of last year and tried to kill it using Tetra
Pond 'Algo Fin' blanket weed control but, although I made several
applications each time doubling the recommended dosage, it didn't work.

Can anyone advise what the maximum dosage is likely to be or if there is
another method that I can use. Obviously, commercial growers must be faced
with this problem, buit I have never seen any signs of it when visiting
nurseries.

Thanks in anticipation.

Eric