Written by: Mary Wang
Gardening in Pueblo, CO is not for the faint of heart. This year alone we have already had seemingly constant winds in May and a sudden snowstorm after Mother’s Day. Really! After Mother’s Day! For weeks it had promised it was spring! Then June arrived and what a start it had. For three days temperatures soared past the 100 degree mark. In my garden I watched as several plants, newly planted during the gorgeous days the week before, shrank away from the heat with drooping leaves. I tell these weather anecdotes not only to complain but also to remind you of some of the challenges we face as Colorado gardeners. So what can we do to help our plants survive these capricious conditions? One thing that helps is mulch.
Mulching is the process in which you cover or add layers to the soil’s surface and over time many good things can happen. The covering or layers applied can be organic such as shredded bark, newspaper, compost, leaves or pine needles. Or they can be something inorganic such as gravel or rock. Mulch is the personal trainer of the garden; it improves the physical condition of the garden’s soil. The improved soil creates a nicer environment in which plants can grow and spread their roots.
Soil improvement occurs gradually in a variety of ways. Foot traffic, hail or machinery, can all compact the soil. When soil is compressed the space between soil particles is reduced. Since there is less empty space between soil particles the amount and flow of air and water in the soil changes, reducing a plants growth. Add a layer of mulch and you can protect your soil from compaction. A mulch layer will also act as an insulator and wind screen keeping moisture levels and soil temperature more constant. It does this by preventing the wind and sun’s rays from directly hitting the soils surface, limiting evaporation and a corresponding increase in the soil’s temperature. Mulch also acts as a barrier to weed seed growth and development by blocking light from reaching them so they remain dormant. As if these benefits were not enough, organic mulch breaks down. As it does so it attracts earthworms as well as microorganisms to the soil. Byproducts of these organisms improve the soil’s texture and add nutrients.
Nitrifying bacteria converts nitrogen in the soil into forms that plants can readily uptake. Microorganisms such as mycorrhizal fungi act with plant roots to increase nutrient and water uptake.
So do yourself a favor this summer, mulch your garden and let it do some of the heavy lifting while you take some time to enjoy your ripening vegetables and blooming flowers.
References:
1) Soil Compaction CMG Garden Notes #215, Master Gardener CSU Extension
2) Mulches for the Home Ground, By J.E. Kelt, Colorado State University Landscape horticulturist and Professor, department of horticulture and landscape architecture. Revised 12/14 from original fact sheet authored by J.R. Feucht, retired 11/97. Revised 12/20 by J. Murgel and M. Platten.
3) To Mulch or Not to Mulch, Johnson County Extension Master Gardeners 2004, K- State Research and Extension, Johnson County.
4) Mulch Basics, Revised by UConn Home and Garden Education Center 2016. Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, the Dean of the College, Cooperative Extension System, University of Connecticut, Storrs.