My pumpkin patch soil has been a bit jacked up for a while now in terms of potassium and phosphorus. The numbers have been too high for about 3 years now so I haven't added any potassium or phosphorus to the soil other than what comes with the compost. My latest soil test came back today and potassium and phosphorus are still high but they are coming back down to where I would like to see them. The thing that pleased me the most is cation saturation is pretty much in balance for the first time. Calcium is at 64.4% and magnesium is at 19.8%. Ideally you want those two numbers added up to equal 80% and we are close enough to that. My potassium is high so that will inhibit a little but I think we are okay.
The cation saturation is difficult stuff to understand but basically it can tell you how well the plants can get nutrients from the soil. This article is a nice simplified explanation of how it works. If you are looking for more information you better get your PHD on because there are lots of articles that are over my head.