In article <MOD$990906.27885@rec.gardens.ecosystems>, J.F.Hensler writes > > > > > > (Terry Mooney) wrote: >> >> > Why doesn't irrigation water have the same dramatic effect on plants >> >that rainwater does ? > >Eliska replied: >> >> I'm wondering that myself. Water conservation proponents say that a >> deep watering twice a week will help a plant develop deep roots and >> good growth. >> After a dry spell here in Florida, during which my plants just hung >> in, we had lots of rain. They flourished - lots of new foilage and >> flowers and growth spurts. >I remember reading somewhere, I can't provide a reference, that rain >water (especially thunder showers) contains a small amount of >nitrogen, in effect applying a top dressing of fertilizer every time >it rains. We too have noticed that rain water is far superior to well >water for all types of growing things... >
I guess that rain falling during thunderstorms may have nitrates in it
formed using the energy from the lightening. But I wouldn't have thought
it was that much, and I'd have thought in 'normal' rain the nitrogen
would be just as a dissolved gas which will be of no direct use to
plants.