help growing collard greens on verticle towers
My husband purchased several vertical hydroponic growing towers last year, and has been trying to grow collard greens. They grow great, but they are very spotted looking, and have a lot of yellow on the leaves. He has tried all kinds of two part nutrients, and still has the same results.
Has anyone grown collards successful using this method?
Is there a preferred nutrient formula he should be using?
He has used a 5-12-26 and a 8-15-36 2 part formulas. Some leaves are green, but the majority are spotted. It would make him a very happy man if he could grown them green!