Perennial ryegrass (Lolium perenne) is a type of grass that is widely used for garden lawns. The reason perennial ryegrass is good for this purpose is because it's hardy, germinates quickly from seed yet spreads slowly, and stands up well to wear and tear. The growing habit of perennial ryegrass makes it ideal for lawns as it's clump-forming and responds well to regular mowing. As well as being a popular lawn grass, perennial ryegrass is widely grown as a forage crop for livestock, and many different forms have been developed for both purposes, including dwarf perennial ryegrass for lawns.

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How to identify perennial ryegrass

Perennial ryegrass in flower. Tim Sandall
Perennial ryegrass in flower. Tim Sandall

Perennial ryegrass identification can be difficult when it is mown short, but is easier if left to grow to its natural height (around 30-50cm). Its stems are green, narrow and blade-like. Its flower spikelets are messy and held on the stem alternately. Other identification markers include the fact that it grows in clumps and has fibrous roots, and that it grows extensively on road verges and unmanaged land as well as agricultural pasture fields.

Value to wildlife

A lawn that is regularly mown has relatively little value to wildlife, though birds such as blackbirds like mown grass that allows them easy access to worms. It's more beneficial to leave the grass to grow longer and cut infrequently – as little as two or three times a year – which benefits many insects and small mammals. Campaigns such as ‘No Mow May’ have introduced many gardeners to the appeal of a longer lawn. The seeds of uncut ryegrass are an excellent food source for seed-eating birds such as finches.

However, perennial ryegrass is not the ideal grass species to use if the main aim is to create a wildflower meadow because it is vigorous and out-performs flowering plants. To convert a conventional lawn into a wildflower area, reduce the vigour of ryegrass by sowing yellow rattle (Rhinanthus major), an annual flower that is semi-parasitic only on grass.


Where to grow perennial ryegrass

Grow perennial ryegrass as a lawn, in sun or partial shade. Perennial ryegrass grows on a wide range of soils and thrives on all but very wet and very dry soils.


How to sow perennial ryegrass

Sowing perennial ryegrass in an existing lawn. Tim Sandall
Sowing perennial ryegrass in an existing lawn. Tim Sandall

Sow seed or buy and lay turf in spring or autumn, onto soil that has been well prepared and is free of weeds and large stones. Perennial ryegrass seed is by far the most economical option for creating a lawn 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. Turf does cost more though, and is a much bigger job to lay compared to sowing seed.

The best month to plant perennial ryegrass turf is when the days are medium in length, in spring or autumn. Laying turf is inadvisable in winter as conditions are usually too cold, wet, and dark for growth. In summer, the weather is likely to be hot and dry, so new turf can usually only be successfully established by regular watering – not only costly, but against the law if hosepipe bans are introduced in periods of drought.


How to care for perennial ryegrass

Mowing perennial ryegrass. Tim Sandall
Mowing perennial ryegrass. Tim Sandall

Mow a new lawn with the mower blades set high, to encourage the grass to form clumps. Thereafter, vary the regularity of mowing according to your needs. For a general-purpose lawn to use for playing, sitting out and so on, a cut height of around 5cm is ideal, which usually means weekly mowing during the growing season. Consider less frequent mowing for areas of lawn that aren’t regularly used.


Pests and diseases

Perennial ryegrass is not susceptible to any pests or diseases.

Advice on buying perennial ryegrass

  • Perennial ryegrass is such a good lawn grass that it makes up a high proportion of most grass seed mixes
  • While most lawn seed mixes don’t usually name the different types of grass, any general purpose or hard-wearing lawn grass seed will be principally made up of perennial ryegrass
  • The exception is ‘fine’ or ‘bowling green’ type lawns, both because of the broad leaf blades of ryegrass and because perennial ryegrass doesn’t thrive if regularly mown very short

Where to buy perennial ryegrass online

Frequently asked questions

What is the life cycle of perennial ryegrass?

Perennial ryegrass germinates from seed within around five days in optimal conditions. A cool-season perennial, it grows strongly in spring and autumn but goes dormant in winter and can enter dormancy in hot summer weather. If not mown, perennial ryegrass bears seeds in summer.

Is ryegrass native to the UK?

Yes. Perennial ryegrass is a European native, including the UK where it grows extensively on verges, in wild places, and fields. Many varieties have been bred for different garden and agricultural purposes.

Does perennial ryegrass die in the summer?

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During periods of drought, the leafy growth of perennial ryegrass may turn yellow and die, but the roots survive, and fresh growth will emerge once temperatures cool and rain falls. For this reason, watering lawns in times of drought is a poor use of mains water, especially as supplies may become scarce as the effects of climate change intensify.

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