Feed them some nutrients. Be careful and follow the instructions that come with the nutrient product(s) you use. Use to much nutrient and they will burn.
KanMan Reviewed by KanMan on . WHATS HAPPENING {yellow not mellow] This is whats been happening after transplanting my 3-3inch babies into large 10 inch pots. I used store bought potting soil only, added nothing to it and have not used any fert's. I only water when the soil feels dry , have 4 flor's 48 inches long 40 watts each hanging 2 inches or less above the plant tops. The older bottom leaves are yellowing and dropping off as the plants grow. I'v been having the lights on 24 hours a day. They are making progress but I'm afraid what looks good on top today Rating: 5