January and February In The Garden: Healthy Soil

Healthy soils are vital to healthy plants and to a healthy ecosystem.  We should cultivate topsoil which is relatively dark in color, active with microorganisms, nutrients, and organic matter (OM), and generally has a pH between 5.5 and 7.5.

As Blackridge’s typically clay soil structure is improved by decomposing OM, our soil absorbs moisture that would otherwise run off, causing erosion and a loss of nutrients for both plants and beneficial soil organisms.  Good soil structure also provides channels though which water and air (Remember that roots need air.) can filter to greater depths to reach plant roots.  OM continually decomposes, so adding it must be a continual process.

If you wish to have your soil tested for pH and nutrient levels, you can find details on how to do so at http://www.aasl.psu.edu/SSFT.HTM .  Soil test kits can be purchased from our local Allegheny County Cooperative Extension Office at 400 North Lexington Street in Pittsburgh (412-473-2540.)  If your soil test results recommend additional nutrients, add them just before planting in the spring. If you regularly add OM to your soil, you will decrease your reliance on chemical fertilizers, since OM promotes a gradual release of plant nutrients. OM alone, however, will not always provide sufficient nutrients for plants. Organic fertilizers may also need to be incorporated into garden soil.  If your soil test results suggest finely ground lime for your soil, the lime should be worked into moist soil two to three months prior to planting.

When you peruse your seed catalogs and visit local nurseries, remember that the roots of native flora have evolved in our soil, and are better at resisting the stresses of our area.  Native plants require less time to flourish because they are already acclimated to the nutrients found in our area's soil. They will require less fertilizer, and there will be less need to change the soil's natural properties. Native plants should be able to subsist on natural rainfall, decreasing the amount of overall water consumption needed to keep your garden healthy and beautiful.