for fruit and vegetable gardeners along Colorado's Front Range
Saturday, March 13, 2010
Turn under winter cover crops
If a winter cover crop of rye or Austrian winter pea was planted in the fall, turn it under a month before planting or seeding. I turned my winter rye under this past weekend adding “green manure” to the soil.
The large soil critters such as the earthworm pictured here (below right) and soil microorganisms will “chew” through the raw roots and tops over the next weeks for soil improvement. I left the soil “rough” and certainly didn’t step on and compact it. That’s an advantage of raised bed gardening – standing outside the bed to work your soil. It will not be tilled again when seeding or planting so the soil structure can be preserved as much as possible. More tilling would simply destroy it and there is no good reason for it.
First, why do you need to wait a month before planting? The living critters working over the plants consume soil oxygen and can create plant health problems if not tilled in ahead of time. Once the bulk of the “raw” plants have been consumed, the soil environment stabilizes and lack of oxygen for plant root growth is no longer a problem.
Second, it’s about more than the buried plants. If it was only the plants we could find a way to chop them into fine pieces and instantly improve the soil. The secret is what the soil critters add to the mix and the squeamish need read no further. Simply know that without them, you couldn’t realize the soil structure and fertility improvement benefits from planting and turning under cover crops.
Large and small critters feed on the buried plants adding substances such as slime, mucus and fungal mycelia. Analyzing these substances show things such as gums, waxes and resins which glue soil particles together. Clumped particles enhance the tilth, porosity, and water holding capabilities of soil – all good things for healthy plant growth.
Take care of your vegetable garden soil and it will take care of you.
Photo credit: Two soil spading photos - Carl Wilson
At Denver Urban Homesteading * Vegetable Gardening - Sat Mar 16, repeated Sat April 13 - both 2 to 4 p.m. * Berry Growing - Sat Apr 20th, 2 to 4 p.m.
At Denver Botanic Gardens * Shrub Pruning - Sat Feb 23rd, 1 to 3 p.m. * Keys to Home Vegetable Gardening - Sat Apr 6th, 10 a.m. to Noon * Berries and Grapes for the Front Range - Sat Apr 20th, 10 a.m. to Noon
* Keys to Home Vegetable Gardening - Sat May 18th, 10 a.m. to Noon
* Berries and Grapes for the Front Range - Tues May 21st, 6 to 8 p.m.
* Follow-on Vegetable Gardening - Wed July 10th, 6:30 to 8:30 p.m.
* Water Wise Landscape Planning - Sat July 20th, 9 a.m. to Noon
* Best Fall Planted Bulbs for Perennializing - Sat Sep 14th, 10 a. m. to Noon
WithThornton Water * Water Wise Landscapes and Gardens - Postponed due to weather from original Apr 15th date. Rescheduled date is Mon May 6th, 6:30 to 8 p.m.
Carl is a speaker, freelance writer and plant consultant working in the Denver area. He is retired from Colorado State University Extension as the long-time horticulturist in Denver. Contact him about programs on vegetables, fruit, perennials, urban landscapes and more. email@example.com