Lolium perenne, perennial ryegrass, is a long-lived species of grass that is extensively used for lawns. It's hardy, tough, quick to germinate, and stands up well to a lot of use. For these reasons, most general purpose or utility lawn seed mixes and turf contain a high proportion of perennial ryegrass, along with other grasses. The exception is ‘fine’ or ‘bowling green’ type lawns, both due to leaf size and because perennial ryegrass doesn’t thrive if regularly mown very short.
The growing habit of perennial ryegrass is ideal for lawns, being clump-forming with fibrous, clump forming roots. Smooth, dark green leaves are glossy on one side and, if allowed to grow long, produce tall stems of spikelets that hold the flowers, 30-50cm high from late spring to mid-summer. Perennial ryegrass is native to Europe and for centuries has been widely grown as a forage crop for livestock. Many varieties have been developed for different purposes.
Perennial ryegrass thrives on a wide range of soil types and is easy to grow. Sow seed or buy and lay turf in spring or autumn. Seed is much cheaper but does take several months to establish into a useable lawn, whereas turf makes an instant transformation and can be used within a short time but is more costly and takes more work to lay. Once established, mow regularly – the ideal mowing height for a general-purpose lawn is around 5cm.
Avoid sowing perennial ryegrass into a wildflower meadow because it is vigorous and out-performs flowering plants. If you want to convert a conventional lawn into a wildflower area, reduce the vigour of ryegrass by sowing yellow rattle (Rhinanthus major), an annual parasitic flower that inhibits grass growth, allowing wildflowers to flourish.
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