Q: I recently heard you advise gardeners to mulch with cottonseed meal, saying that it provides nutrients to azaleas, blueberries and raspberries. However, when I went to the feed store to buy some, I was told to use cottonseed hulls. Which do you advise?

A: Although they are not the same, either could work fine. Cottonseed meal is a by-product from the extraction of oil from cottonseed. Cottonseed meal is the product most often found in garden centers but it is also found at feed stores, sold as a livestock feed additive. The product is much cheaper in the feed store because it is not sold or labeled as a fertilizer – but it is the same as the product you buy at a nursery.

Cottonseed hulls, on the other hand, are the seed coats from cottonseed. They are removed before oil extraction and are also used by cattlemen as a feed additive. As you can imagine, hulls are high in fiber and are used as roughage where good quality forages are scarce.

The difference between the two is in the nutrients they possess. Cottonseed meal is approximately 6-2-1 (nitrogen-phosphorus-potassium) while cottonseed hulls are usually 1-1-1. I recommend spreading a two inch thick layer of cottonseed hulls OR a one-half inch layer of cottonseed meal under the plants mentioned above.