Foundational for any plant to grow is water and air, this takes place in soil. The plant borrows from the soil ammoniates and nitrates to actively and primarily to grow. Soil acidity pH takes a crucial role in this exchange. Soil typing is also crucial as this determines how long primary and secondary nutrients stay in the root zone of the plants. Our approach to fertilization should not be to ask my neighbor, the S#0tts guy at Lowes, or any other retail garden center. It should be responsibly based on a recent soil sample, with a responsible 3rd party laboratory doing the test. And lime and fertilize according to the test.
Any farmer that has a cash crop will sample at least biennially and most annually. They pay for this diagnostic tool and nematode assays as well. Then they pay someone to long hand them a plan for fertilization and lime application. This resource is invaluable. “If you think the cost of an educated professional is high, try ignorance!” This practice is wasteful and even primary units such as Phosphorus and Potassium are not needed as much as extended release Nitrogen. I don’t use them with a soil sample recommendation. I have seen toxic levels of Phosphoric acid in my home county. The cell walls of Bermuda grass are stiff as a dry twig and no bedding plant will grow. Potassium will form an alkali, if soil pH goes above 7.3 or higher, making opportunistic problems for annual sedges and weeds. With materials costing what they do today and environmental concerns with rain water runoff ending up in our creeks and reservoirs. Can we – should we- take the chance?
I have been doing soil sampling for nearly 30 years now. Most problems we encounter on the surface have an underlying cause in the soil. There are several new technologies on the market now that greatly speed absorption and reduce rain water leaching into the ground water. I think it is a responsibility to be well read on these issues because many people trust and look to me for an informed decision, as a licensed landscape professional. I hope this post will stir up a concern and desire to reduce the use of unnecessary chemicals. Use a soil sample – Do it right!