Clover species for grassland reseeding

From management of clover to the differences in leaf size, our resources will help you to utilise clover in a grassland reseed.

• High protein (typically over 25% crude protein (CP))
• Palatable (D-value 75–82) so high intakes by livestock
• Nitrogen fixation by the clover plants means less artificial nitrogen fertiliser required for grass growth
• Fits well into forage or arable rotations
• Benefits soil fertility and structure
• Drought-tolerant with higher summer production than grass-only swards
• Relatively easy and cheap to grow once established
• Increased first cut silage/early grazing yields with strategic nitrogen applications

Clovers can replace some or all bagged nitrogen in both conventional and organic swards. How much nitrogen is fixed depends on the clover content in the sward.

Disadvantages of clover include:

• Clovers require warmer soils for growth to begin (8°C compared with 5°C for grass)
• Soil pH needs to be 6–6.2 and P and K indexes above 2 (as with grass)
• Extra care is needed when ensiling high-DM crops as the leaves shatter easily

Clovers limit weed-control choices as many weedkillers are not suitable for use in a grass mix that contains clover.

White clover

White clover is a perennial legume. The key to its survival and production potential is its multi-branched creeping stem (stolon), which provides sites for new leaves, roots and flowers. The stolon stores carbohydrates and proteins, giving the plant the ability to overwinter and regenerate in spring.

Red clover

Red clover is a short-lived perennial legume that typically lasts for two to four years. In contrast to white clover, it has an upright growth habit and a strong, deep taproot. Red clover is typically higher-yielding than white. Historically, it has been much less persistent than white and as a result was used only in cutting leys. Improvements in management and variety breeding have meant that, with care, red clover can now be grazed by cattle without killing the plant. Red clover can also be used as a break crop in mixed farming systems due to its ability to improve soil structure and soil nitrogen supply.

White and red clover varieties are listed in the Recommended Grass and Clover Lists.  

White clovers are categorised on leaf size.

Small-leaved white clover suits continuous, hard sheep grazing.

Medium-leaved white clover suits frequent cutting and rotational grazing, and cattle grazing.

Large-leaved white clover or red clover suits cutting and rotational grazing. Larger-leafed varieties tend to be higher-yielding but are less tolerant of grazing and compaction. If selecting varieties for cutting, choose large-leafed varieties for maximum yield.

White clover typically fixes 150 kg N/ha, although it can be up to 280 kg N/ha. It suits both grazing and silage and can increase yields by up to 15%, depending on clover content and N inputs.

• Sowing is best in April to August, adding or replacing 2.5 kg/ha (1 kg/acre) seed
• Broadcast or drill to an optimum seed depth of 5–10 mm
• Clover can be over sown after first-cut silage or after weed control in a reseed. Avoid introducing clover until the spray residual has been denatured
• Target 25–35% of sward DM as white clover

For every 10% increase in white clover, the protein content of forage will be 1% higher. In late-summer swards, crude protein content can increase to 25%.

Higher N levels applied to the crop reduce the amount of N fixed from the atmosphere. Be patient for full N-fixing effect in grass production as it takes a full season or more before it achieves full N-fixing ability.

Red clover swards can fix between 200–300 kg N/ha, producing the same yield as a short-term ley with the same amount of N applied.

• Sowing is best in spring, or mid-July to end-August, replacing 7.5 kg/ha (3 kg/ acre) of grass seed with clover seed
• Broadcast or drill to an optimum seed depth of 5–10 mm
• Best sown with grass, especially hybrid ryegrass, to optimise forage yield
• Crude protein content in silage can be up to 19%, depending on the amount in the sward and cutting date
• Cutting too low, overgrazing in autumn or winter or wet conditions damages plant crown and can reduce persistency
• Soilborne disease and pest control create a need for a rotation, with breaks of five to eight years between red clover crops

High protein content makes it excellent for finishing lambs and cattle in autumn. However, it is unsuitable for grazing breeding ewes during tupping and six weeks either side.

Other clover varieties are offered in mixtures, particularly for cover crops or green manures.

Berseem (or Egyptian) clover is a fast-growing, annual clover, which makes it good to use in arable rotations. It will fix nitrogen once established and will produce a reasonable amount of growth. It can be grazed by stock carefully if introduced slowly with a fibre source. It is easily killed by frosts.

Crimson (or Italian) clover is a fast-growing, annual clover that is more winter-hardy than berseem clover. It will fix nitrogen once established and will produce a reasonable amount of growth. It can be grazed by stock carefully if introduced slowly with a fibre source.

Subterranean clover is a slow-growing, annual clover that is native to north-west Europe but grown widely in Australia and America. It can thrive in poor-quality soil and is an excellent weed suppressor. It is self-fertilising, produces its seed underground and regenerates itself for the next year.

If you would like to order a hard copy of the Recommened Grass and Clover Lists or the Establishing and growing clover manual please contact:

Email: publications@ahdb.org.uk

Telephone: 0247 799 0069