Our pea plants are up about 3 inches. We live in south central New Mexico. The soil is sandy but we've amended it with peat and compost, plus we are using an organic fertilizer. About a week ago, the plants began turning yellow. Is this a lack of iron? If not, what is it and what can we do about it? We water in the morning and the late afternoon. The water here has a high calcium content.
Pea Plants Are Yellowing
Certified GKH Gardening Expert
It is iron chlorosis, but typically, the plants get it because they simply can't get to the iron in the soil. Given what you described, I would say either you have too much phosphorus or the pH is too high. This article will help with fixing that: https://www.gardeningknowhow.com/plant-problems/environmental/leaf-chlorosis-and-iron.htm