I water during the day, this is so that the water doesn't linger on the plants overnight and cause mould.

If your light is very close to the plants and heat is a issue, I would water very carefully at night.
stone_sensation Reviewed by stone_sensation on . watering question i was wondering if it matters when you water as far as lighting goes. would it be more beneficial to water during the plant's daytime or nightime? Rating: 5