Some of my in ground plants and more than a few hibiscus in pots are dropping yellow leaves. After reading the newsletter below, I'm wondering if it could be lack of sulfur. Bill Luedecke, my gardening friend and Hill Country master gardener, wrote:
When we see the leaves on our plants turning yellow, we usually say it needs more nitrogen. However, it could be a lack of sulfur in the soil. Apparently, there is less sulfur these days in the rainwater. Around here we don’t even have the rainwater. The drought seems to be causing a sulfur deficiency domino effect in our gardens.
Immobile nutrients, including potassium, phosphorus, and zinc, remain close to the surface, while mobile ones, such as nitrogen and sulfur, may still be available deeper in the soil. Here in the Hill Country, soil tests show that we have lots of potassium, however, the soil will not give it up and we still have to add potassium to our soil.
Remember, your soil is hungry for nutrients after the dormant winter so be sure to test your soil. If in doubt, you can always add organic compost (and with it, a broad spectrum of nutrients) at any time.
