Ryegrass
General
Ryegrass varieties are certainly eligible to be sown as green cover crops. Due to their intensive rooting, they are even the best choice on soils prone to silt.
Sometimes the first cut is harvested (grazing, forage harvesting) and the regrowth and the stubble serves as the actual green manure.
In general, preference is given to tetraploid varieties: they have a quicker start, better growth recovery after winter and form a fast covering, healthy crop. The tetraploid varieties for the different grass species registered on the Belgian Variety List are listed under 'grasses for green fodder purposes'.
On heavy soils, ryegrasses are sometimes sown under cover crops (cereals). This complicates the cultivation of the main crop, but after harvesting, tillage is unnecessary and the soil is quickly covered. Perennial, Hybrid and Italian ryegrass are suitable for this. For Italian ryegrass under cover crops, choose varieties that do not form spikes in the year of sowing, in order to prevent storage in the next crop.
When sowing after the main crop (end of July – October), the sowing time and purpose determine which ryegrass to sow.
Variety choice when sowing ryegrass as a green cover crop
| Variety | Purpose | Time of sowing |
|---|---|---|
| Perennial ryegrass Hybrid ryegrass Italian ryegrass Westerwolds ryegrass | Green cover Green cover Green cover Green cover | August / September August / September August / September August / September |
| Italian ryegrass Westerwolds ryegrass1 | Fodder production in the autumn + green cover Fodder production in the autumn + green cover | August August |
| Perennial ryegrass Hybrid ryegrass Italian ryegrass | Green cover + fodder production in spring Green cover + fodder production in spring Green cover + fodder production in spring | August / September August / September August / September |
1Westerwolds ryegrass can be sown slightly later than Italian ryegrass: emergence and early growth are slightly faster