What should I add to the soil to be sure plants will have enough nutrients?

Question:

I planted a new flower garden last summer (2020). I dug up and removed the old sandy soil and put about 5″ of a soil and compost mixture down. I planted all new plants in this area. The plants thrived last summer and fall season. I am wondering what I need to add to the soil for this year to be sure plants will have enough nutrients?

Answer:

Tori Lee Jackson, Extension Professor of Agriculture and Natural Resources, University of Maine Cooperative Extension Androscoggin and Sagadahoc Counties

The best way to know what your garden soil needs is to do a soil test. You can pick up a soil testing kit at your local Extension office (Waldoboro for you), or have one mailed to your home. It comes with instructions and a box to put your sample in. It is then sent up to the lab in Orono for analysis. Each test costs $18 and you will receive your results in about two weeks once it has been received. The one macronutrient not measured is nitrogen, as it is fairly ephemeral and varies with rainfall or other events. You should always plan to apply any needed nitrogen to your plants each year. For more information about soil testing, check out Bulletin #2286, Know Your Soil: Testing Your Soil.