white substance?

bonsai_monk · Posted: Sat May 07, 2005 6:50 pm Post subject: white substance?

On my chinese elm, on the leaves there is a white substance on them. It looks a bit like bird poo but on a much smaller, thinner scale. I washed it off and sprayed it with insecticide but it keep forming again. Does anyone know what it is and how to remove it?

Stymie · Posted: Sat May 07, 2005 7:14 pm Post subject: Re: white substance?

Its difficult to say, sight unseen but may be residual salts from fertiliser. Wash it off again and try watering direct onto the compost without splashing the leaves. This will tell us if it is something in the water. You may live in a hard water area which means calcium deposits in your tap water. Try to save rainwater and use that if you can or at least age the water for at least 24 hours before use. I hope that this helps.

bonsai_monk · Posted: Sat May 07, 2005 7:21 pm Post subject: Re: white substance?

Im not sure what the water is like around here, but I was looking around on site and I think it may be 'powdery mildew'?