Good evening, I have planted several containers over the past couple weeks and I have noticed that some of the plants in them started to develop a purple discoloration of the leaves within a few days of being transplanted. Specifically, the mint and catnip I planted in a large stock watering tank (with drainage holes cut in the bottom), and the sweet potato vine I planted in a pot with some other foliage plants, have developed this discoloration. I have read that it could be any number of things, including too much water, too little water, a phosphorous deficiency, and other things. I have attached some pictures below. It seems that the new growth on the catnip and the mint is coming in with normal color. I added some organic fertilizer to the containers with the herbs last night, but it is obviously too soon to see if that would help the problem. I was also concerned that the stock tanks were placed too close to a SW facing wall of our house, which has white vinyl siding. I thought that the plants were getting scorched from the sun and the reflection of the sun off of the siding. I used Sta-Green potting soil for container gardens, and I don't know if that is a good quality potting soil, or not. It says it has fertilizer included and would feed for up to 9 months. Any thoughts you could share on the situation would be greatly appreciated. Thanks,