tomato seedlings turning yellow
by Bill Wing
(Delta ON)
using miracle grow seed starting mix. thy are in a window facing west also are 2 hallogen lamps about 2 feet over the plants. they are starting to turn yellow even though they seem healthy.
Doug says yellowing leaves are a symptom of stress. Too much food / not enough food. Too much light / not enough light (probable in this case as halogens aren't grow lights and are too far above the plant). Too cold a temperature, too much water/too little water.
Those are the causes - and without knowing which / what they are, it's hard to say. But yellow is a stress response.
