Newsletter‎ > ‎May 2017‎ > ‎

Amending Soil

posted May 4, 2017, 3:16 PM by Kristin Snell

by Darlene Markey, Sweetland Garden Mercantile

Half of a plant’s life is above ground, where sun, air and water supply Hydrogen, Carbon, and Oxygen. Half of plant’s life is in the soil, where a plant derives Nitrogen, Phosphorous, Potassium and a whole bunch of other macro and micronutrients. Our first task, as gardeners, is to help our soil become a rich reservoir of nutrients for our plants to choose from. But of course, the reservoir needs to be balanced. 

Often times I get a soil report from a customer. Inevitably it shows the customer has an abundant amount of phosphorous and calcium. In our desire to have big flowers we often add too much of these things into our soil.  So our first task is to TEST OUR SOIL. 

Home soil tests kits and professional tests are available at most garden stores. The first thing to test is your PH. PH is important as different nutrients are available to  plants at certain ph levels.  Phosphorus and Potassium are chelated best in a more alkaline environment. Nitrogen is leached out in an acidic environment. Iron, Manganese, Zinc, and Boron like are more usable in an acidic environment.  

Professional tests show the macro and micronutrients, such as calcium and zinc, that are in your soil. 

Why, you might be asking, is there usually too much phosphorous in a soil test? You can add all the nutrients in the world, but unless they become available to the plant in a usable form or they leach out, they remain in the soil. Phosphorous and Calcium are two of the hardest minerals to chelate. Chelate-the ability of a plant to utilize a nutrient, is achieved mostly through microbes.  Plants exudate sugars and proteins to nutrients, who in turn release nutrients in a plant usable form.  

So as important as getting your soil tested, is adding healthy microbes to your soil. A good way to do that is by adding new compost. 

Choose a compost that is fully composted, rich in humus, and has no salts. Add it at the rate of 1-2” over the surface. Then add amendments, such as crab meal, glacial rock dust, alfalafa meal or humic acid, that feed the microbes in the compost.   

To learn more,  consider taking an Soil Amendment class with Dar. The next one is May 9, at 6 pm, at Sweetland Garden Mercantile. RSVP needed. 530-292-9000, Dig it!