Greetings, Netters, and Best Wishes for a Healthy New Year. I am mystified by a problem with seedlings of Bauhinia species, probably B. monandra, growing in small pots. The seedlings are a little over a month old, and were doing fine until about a week or two ago, when the young leaves began to look chlorotic. The symptoms are getting worse. They are growing in a mixture of compost, topsoil, aged chicken manure (mixed with wood shavings), with some wood ashes and a little coral sand. It looks to me like some sort of deficiency, but I don't think it's nitrogen, since it is on the younger leaves. I thought of iron, but this red topsoil should have plenty of iron. I am now beginning to see some necrotic spots on the leaves of a couple of plants, and even veinal necrosis in one plant. Does anyone have any suggestions? Could it be a calcium deficiency? Maybe I should add a little lime? ... or maybe it is some sort of toxicity?
I think Bauhinia is a member of the Fabaceae, so perhaps it's waiting for rhizobia. So find a mature tree, dig up some roots, select pink nodules and grind up and add to the soil and see what happens. And perhaps don't add chicken manure and wood shavings next time.
This is my guess. Hoping someone will put us straight!