On 21 Mar 2011, at 10:22, Donald Barnett wrote: > Hydrogen peroxide, yes. You can also use some other ones like zerotal but that may > be for greenhouse operations. If you can get 3% basic hydrogen peroxide from a > grocery store then use full strength, just spray with a basic spray bottle after > every watering. The stronger stuff I'll get back to you on. I'd have to check some > notes. You can buy 35% hydrogen peroxide (I get mine from a farm supply place) but unless you have experience in dealing with hazardous substances, stick with the stuff from the grocery store. In high concentrations, hydrogen peroxide is a strong oxidizer, thus something of a fire hazard. It will raise blisters almost immediately if splashed on skin. Nothing to fool around with, even if it is a lot cheaper. There's a 10% version used in hair salons, but even that is something to be cautious about. Buying the 3% grocery store stuff also has the advantage that it doesn't have to be diluted, so there's no risk of forgetting to do the dilution (or getting it wrong) and killing your plants with high concentrations of the stuff. BTW, Walmart (spit!) has 3% H2O2 at a very good price here. Check the Walmart near you - they might have it at a good price too. -- Rodger Whitlock Victoria, British Columbia, Canada