Rain water users here?

My rainwater is of no use to me at all... the ph is 7.5 (collected in the middle of my yard, not falling from a downspout or off the roof) so I may as well get it out of my tap. Besides, as both GrowCN and loganchan say, it's not the PH you're after when you use rainwater...

J'ai une récupération d'eau de pluie. Et le seul problème que tu pourrai avoir et que, y en as pas, les plantes vives avec la pluie ainsi que de l'eau de ruissèlement depuis toujours. bien sur si tu as une usine polluante juste a coté..

A lot depends on how you collect the water. Contamination has a big affect on the water quality. If collecting runoff from a roof there can be bird poop, dirt, pollen and other things being washed off and into your bucket. I find it also depends on how frequently it rains. If it has been a long time since there has been a hard rain the water can be quite dirty. If you get heavy rains frequently the roof gets rinsed more often and the water can be cleaner. I don't bother collecting water in spring. The pollen from trees is so heavy collected rainwater can have a heavy scum on the surface. During the heat of summer it may go a month without a hard rain so the roof can get very dirty so when it finally rains the water is just nasty. OK for immediate outdoor garden use but nothing I want to keep for more than a few days.

its not the PH you are after with rainwater, it is the dissolved oxygen and water soluble nitrogen. the oxygen allows roots to grow in the presence of water, nitrogen is notoriously difficult for plants to absorb. after 18 to 24 hours these elements will have evaporated back into the atmosphere.