Cornfield annuals as nurse cover
Meadow mixtures which contain perennial grasses and wild flowers take at least one full growing season to establish full ground cover, and these perennials usually only flower in their second season.
For quicker results when sowing a meadow mixture one option is to combine sowing meadow seeds with a cornfield annual mixture as a temporary nurse cover. This will help fill space and to provide some flowering colour and interest in the first season.
When using this method both mixtures are sown together at the same time on to a clean, prepared, bare soil seedbed. Sow the perennial meadow mixture at its full normal sowing rate (4g/m2 as you would when sowing without nurse cover) as this will deliver the long-term ground cover and diversity. Add cornfield annuals to this up to the full sowing rate for cornfield annuals sown alone (2g/m2) - total combined sowing rate up to 6g/m2.
A cornfield annual mixture can be very successful as nurse cover. The main advantage of using cornfield annuals is that the mixture will give a colourful display of flowers in the first summer. Against their use are their cost and the disappointment that follows their disappearance the following year!
We have seen some excellent results following the use of cornfield annuals. It would seem that the growth of the annuals in the early summer can suppress weed growth, and moderate the vigour of the faster growing perennials and grasses to produce a more open and balanced sward. Yellow Rattle also has a better chance to complete its (annual) life cycle under this regime.
Note: It is very important, particularly on fertile soils, that the annual growth is cut back as soon as flowering declines or as soon as the cover vegetation collapses (usually late July from autumn sowing; early August from spring sowing). The cuttings are usually substantial and must be removed. This cut will reveal the developing meadow mixture and allow it to grow and develop into the autumn unhindered. A delay in cutting will compromise the main sowing, particularly if the cover vegetation has collapsed. Do not wait for the annuals to set seed, there is no point as they cannot grow in established grassland.