Wednesday, 5 May 2021
Deep-rooting crops that are good to fill the summer grazing gap also help to improve soil structure and fix nitrogen. However, the 21st century mix isn’t a monoculture; it includes three different species and makes an ideal entry into a reseed on the grazing platform.
It can also serve as a 3-year break crop, or fulfil a role for those wanting to increase sward diversity, says Helen Mathieu of Germinal Seeds. “Traditional short-term crops are the brassicas: a small seed, needing a soil temperature of about 10°C, sown at the end of April/early May for grazing from 2 months. They fill the grass gap, but shouldn’t supply more than 25% of daily intake for milking cows, otherwise you will get milk taint,” she explains.
A modern mix of drought-tolerant plants for drier farms and lighter soils now includes plantain, chicory, red clover and white clover. Most are sold as a companion to perennial rye-grass and may include some lower output grasses, such as timothy, meadow fescue or festulolium. They are lower in energy and persistent, says Helen.
“Herbs and legumes like slightly warmer soil temperatures and grow throughout summer. They have a denser, deeper rooting system and a waxier leaf that resists desiccation – plus legumes fix nitrogen.”
One note of caution, she says, is that herbs are slower growing and not all are persistent species. “It’s important to put mixes together that are balanced. Plantain and chicory are competitive; they have good early vigour and establish well. Others are less competitive and – even when properly established – don’t provide enough biomass to contribute to the sward. You want there to be a good percentage of all the species in every mouthful.”