I read an article about a professional grower's gardening methods in a popular cannabis culture magazine that suggested that the best time to foliar feed is during the plant's dark cycle, before your lights turn on. Also, to add a wetting agent, a.k.a. a surfactant, to your foliar feed solution, which helps increase the solution's absorption by allowing the liquid solution to spread more evenly across the leaf's surface. The solution she used was made from the General Hydroponics Flora series nutrients, no more than 1 t Flora Micro, 1 t FloraGro, and 1 t Flora Bloom, per 1 gallon of water. I've been using this mix on my vegging plant for several weeks now, starting with a very weak solution of 1/4 t of each nutrient per gallon water, and slowly increasing the amount of nutrients to water. I allow it to fully absorb until the leaves are dry, and before their lights turn on for the day. About once a week I'll spray the leaves with plain 'ol distilled water, to help rinse off any buildup that may have accumulated on the leaf surfaces. While the foliar feed absorbs, I make sure the plant has good air ventilation, to discourage any mold or mildew from growing on the wet leaves. It does seem to be encouraging more branching, and the leaves look nice and healthy. I'd probably see more significant results from the foliar feeding if I used the full strength mix of 1t/1t/1t per gallon, but this early on in the plant's vegetative stage, I prefer to err on the side of caution and under- foliar feed rather than over feed - I can always add more.