I have some Afghan in solo cups filled with FFOF & it looks healthy to me; however, it's 2 most bottom leaves are yellowing & looking like they will fall off some time.
Could this be a nitrogen deficiency, despite them constantly praying & not really looking pale. I thought FFOF was more than enough nutes (maybe even too much) for young plants in solo cups?
Foliar spraying in general is using a diluted solution to spray directly on your leaves, which absorbs them. You can fertilize by using a diluted nutrient cocktail, or it is a useful too for figuring out lockouts and stuff, since you can apply possible remedies and bypass any root problems you might be having. In other words, for example... if your plant can't get enough magnesium because of soil Ph issues, a foliar application of a solution that contains magnesium is sprayed on the leaves. The plant gets the magnesium, looks better, and you know the problem is a lockout in the roots because things got better when you bypassed them. Foliar feeding is fairly common, although mostly using homebrew concoctions and/or teas.
Foliar spraying in general is using a diluted solution to spray directly on your leaves, which absorbs them. You can fertilize by using a diluted nutrient cocktail, or it is a useful too for figuring out lockouts and stuff, since you can apply possible remedies and bypass any root problems you might be having. In other words, for example... if your plant can't get enough magnesium because of soil Ph issues, a foliar application of a solution that contains magnesium is sprayed on the leaves. The plant gets the magnesium, looks better, and you know the problem is a lockout in the roots because things got better when you bypassed them. Foliar feeding is fairly common, although mostly using homebrew concoctions and/or teas.