Can you please tell me the best way to control couch in a commercial mixed crop/vegetable production system. I would like to avoid the carbon destroying process of continual cultivation over a dry period.
This should not be a problem in an organic rotation. If there is a problem then it should be dealt with before planting. That means a cultivated fallow in the summer is required. Couch is shallow rooting, use a rotatiller at shallow depth to cut up the rhizomes into small bits. Use shallow cultivators over a 5-6 week period as weather permits to keep rhizomes at the surface to dry out. Check the conditions by walking the area with a fork. When control is indicated continue with normal rotation. In a 6 year rotation only one such period of intense cultivation should be required and if the job is done well because of favourable weather then it could be even longer before such a technique is repeated.