Yellow Rattle Seed Establishment and Management
Yellow Rattle is a semi parasitic plant which needs grass to establish. It can weaken the grass that is there and to help open up a grass area so that wild flowers may flourish along side the grass.
Establishment
The seed must be sown in the autumn as it needs to be chilled over winter to trigger its germination the following spring. It can be sown as part of a mixture or on its own, into established grassland as prepared below. Sow at about 0.5 grams per square metre. The most suitable site for the seed will be grassland of low to medium fertility. With a balanced sward which is not dominated by coarse vigorous grasses. Prepare for sowing by cutting the grass very short (25mm) or by grazing hard and open up the sites for germination, by harrowing, raking or lightly disking. Aim to create up to 50% bare soils. Broadcast the seed on the prepared surface and if possible roll afterwards.
Managing swards with yellow rattle
Yellow rattle is an annual with short lived seed. It therefore needs a chance to set seed each year. Cutting or grazing too heavily between April and mid-July will eliminate yellow rattle by preventing it seeding and should be avoided. Traditional meadow management should be based around an early August hay cut or cut. This provides the species with the best opportunity to set seed. For the seed to scatter during the process of haymaking, autumn grazing, mowing or harrowing is also important as it will help keep the sward open. This provides new areas for the yellow rattle to establish in following years.
Yellow rattle populations tend to fluctuate in meadows from year to year. This may be a reflection of the balance of the yellow rattle plants and their host plants in any one patch. Establishment is rather unpredictable; results will vary from one year to another and from one part of the field to another. The reasons for this are not always apparent, but having an open sward structure seems to be the most important factor. To source some Yellow Rattle seed click on the link below.
