I have 1000 watt MH bulb about 20" above plant top. The top leaves are turning slighly yellow. Is this normal? Possible burn? Thanks pics Login
Yellow upper leaves indicates either sulphur or iron deficiency, mix 1 tablespoon Epsom salt to gallon of water and use till condition improves for sulphur, for iron folar feed with rusty water, use a combo of both just to be sure