Cover Crops - 2
Updated: Oct 30
The answer to the maiden’s prayer but what exactly are they doing? We talked about these in the August Blog so I thought we should explore a little further…
AHDB (Agriculture and Horticulture Development Board) Information sheet 41 begins by saying “A cover crop is a non cash crop.” So from that statement there is no financial benefit from growing one?
They do act as a “green manure” recycling nutrients that may otherwise be lost. They also add water back into the soil and an amount of dry matter which is then decomposed by numerous organisms as a food source.
The greater the bulk of crop produced the greater the benefit (recycling) effect. To achieve bulk you need time. Establish the crop after harvest, spray it off before Christmas that is 8,10 or 12 weeks. Dry matter production in the range of 2 to 18 t/ha with a likely return of 5 t/ha for a good crop.
That is 5 t/ 12 weeks or 0.4 t/ week.
A wheat field cut 14th August, drilled to cover crop the next day. Sprayed off and drilled to wheat 10th October. A total of 7 weeks or 2.8 t of dry matter returned to the soil. Not as good as organic manure applications but better than chopping straw this autumn. But… spending £40-100/ha on seed, fertiliser, slug pellets, labour and machinery to get this. Is this why the AHDB opening statement is “A cover crop is a non cash crop” ? The Photos: 1 Canary Grass 2 Buckwheat and Linseed 3 Phacalia and Linseed
4 Forage Rye 5 Forage Rye