Answer: Yellowing can be a sign of transplant shock if the plants were insufficiently acclimated or hardened off prior to planting, it can be a sign of overfertilizing and it can be a sign of overwatering. You might want to check the soil moisture (it should be evenly moist but not soggy wet) before watering and if you think it is transplant shock, wait a bit and see if they come out of it. You might also take a careful look and check for pests such as aphids. These can be rinsed off with a spray of water from the garden hose or can be treated with insecticidal soap. There is also a possibility that there is a soil problem, but the only way to check that is to run some soil tests and find out. Your County Extension should be able to help you with the tests and interpreting the results; be sure you tell them what the problem is when you discuss the results.
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