I have recently regraded my front yard after some foundation work and added top soil in most areas but some areas are still primarily sticky clay. I have several weeks before it is prime time to seed a new lawn and have sent in soil samples for a detailed analysis, but are there general amendments I can add to improve the clay while I'm waiting for the analysis results? I've read mixed theories on whether or not gypsum is effective in our area. Is there anything else I can be tilling into the soil until I'm ready for seed? Thanks!
Thank you for your question. Waiting on the soil test results would be recommended before adding fertilizer. Without the results, it would be just guessing what is needed. Gypsum is not recommended for Kentucky lawns, or lawns in Clark County, even though it is applied in other states at times to alter soil pH. In Kentucky soils, gypsum is not effective at changing soil ph or improving soil structure (AGR-214: "Liming Kentucky Lawns"). Depending on where you are located in the state, your soil ph may not need to be raised. It may actually need to be lowered. If that is the case, applying lime or gypsum could have a negative effect on your lawn. Again, the soil test will give you a better view of the soil pH, and nutrient needs. So it is best to wait on those results. The only thing that you could add that would be recommended without soil test results might be a source of organic matter. Possibly a good certified compost, or manure. Adding organic matter is always a benefit. If you would like to know more, it would be good to contact the county extension office. You can contact me by calling 859-744-4682, Mon.-Fri., 8 am to 4:30 pm, if you would like. There are also several UK lawn fertilization publications available. I am sure your county agent would be glad to assist you.