Now is the time to be thinking about your autumn sown cover crops and getting seed ordered. Winter barley harvest is well underway and cover crops should be established as soon after harvest as possible to make the most of any moisture in the soil. For those planning to sow after winter wheat, make sure you have all the seed in store and get the drill ready to chase the combine out of the field. Once we get to late August / early September each day you lose by not drilling has a real impact on cover crop development.
Remember the key questions to ask:
- 1. What am I trying to achieve with my cover?
- 2. Rotation:
a. When is my drilling window? Do I need a mixture which will cope with being drilled later into September?
b. Will it be over-wintered and if so do I want a frost hardy or a frost susceptible mixture?
c. Do I need to consider club root or other potential disease carry-over issues?
- 3. Am I dealing with any nematode problems?
If you are new to using soil health plants, keep the mixtures simple and focus on key areas of soil improvement:
Use oilseed radish to help break through the compacted areas. An extensive lateral root system will also work through the upper layers of the soil.
Try rye or Japanese (black) oats. Their extensive and fibrous root system will help take moisture out of the top layers of the soil.
Phacelia is an excellent nitrogen scavenger, as are brassicas. If the soil is also compacted, mix phacelia with oilseed radish to allow the phacelia roots to really get down into the soil.
Vetch and clover are the obvious choices here. However, it is worth remembering that if sown too late the plants won’t have time to develop the nitrogen fixing nodules. Definitely best if sown early.