Growing tomatoes in clay soil
The best way to answer this is with a soil test. I'd encourage you to soil test this garden and we can make a fertilizer recipe for the crops you are growing base on what is available in the soil. UK has a good information publication on how to take a soil test. You can pick up testing tools and bags here at the Lincoln County Extension Office, bring the soil back here and we will have it tested in our Lexington Laboratory.