With the production and environmental benefits of diverse swards growing, the case for mixing clover with grass seed is becoming increasingly compelling. While red and white clover share several important attributes, such as providing high levels of protein and the ability to fix nitrogen, they have differences that will be revealed in this red clover silage feature.
In this update, Germinal grass and forage expert William Fleming focuses on how to realise the full potential of red clover silage and we hear how one farmer has incorporated an increasing amount of red clover into his rotation.
Reduced need for applied nitrogen
The high protein content of red clover is one of its greatest attributes for producing high-quality silage. Not only is there more protein than in grass silage – around 3% higher on average - but more of it is available to livestock due to the enzyme polyphenol oxidase (PPO) in red clover slowing its breakdown in the rumen.
Its nitrogen-fixing ability not only benefits the clover, but its companion crop too, most commonly a perennial ryegrass, reducing the requirement for applied nitrogen. It also leaves residual nitrogen behind for the following crop.
The reduced requirement for applied fertiliser is one of the advantages seen by Tony and Michael Ball since they introduced red clover onto their dairy farm in Derbyshire.
Red clover silage in dairy farming
Tony and Michael Ball sowed their first field of red clover in 2018 and are now growing 125 acres in a rotation.
“We’d been growing white clover successfully so wanted to see what benefits red clover could bring. We found it performed very well so as fields came back into grass, we added more red clover.
“We’re really pleased with the silage yields, aiming for a first cut in early May to coincide with making grass silage so we’re not opening the clamp more than necessary. We expect to take three or four cuts.
“We find in the very dry periods, when grass growth slows, the red clover just keeps on going, so we’ve used it to graze youngstock. We also let it go into flower at least once in the dry so it can build up its root reserves for winter.
“As we try to reduce the intervals between cuts to gain the best quality silage, using red clover within our Aber HSG 2 Multi-Cut mix automatically appealed and has performed well.
“We’re certainly putting down less nitrogen fertiliser. Unsure in the first year, we probably didn’t pull it back as much as we could have done, but now use minimal amounts. A little early on (40 kg/ha) with some sulphur (45 kg/ha) to give the grass a boost, and a bit of slurry after first cut, but nothing more after that.”
Red clover silage management
To gain the best silage crop from red clover there are a few important points to check during harvest and in the clamp.
After allowing red clover to flower in the first year to encourage good root development and aid nitrogen fixation, taking the first cut between bud development and early flowering the following year is ideal.
Where red clover is grown with a companion grass, the crop proportions in the cut will change as the season progresses. Starting with a greater amount of grass to clover, this will reverse by the third and fourth cuts.
Handle red clover with care
Unlike white clover, red clover only grows from its crown so it must be protected during cutting. If it’s damaged during harvest, the persistency of the crop is lost. To avoid this happening, cut to a height of around 7-10 cm.
Guarding against leaf damage is also important to protect red clover’s rich protein content, much of which is found in the leaves. Disengaging the mower conditioner and not tedding will both help to prevent leaf shatter.
Red clover is low in dry matter (DM), so allowing the mown crop to wilt for up to 48 hours is essential to retain its high nutritional value. Aim to ensile at 25-30% DM.
Be prepared before cutting
As with ensiling grass silage, good clamp preparation reaps reward, with the added benefit of red clover silage being more aerobically stable helping to keep it in optimum condition.
When grown with a perennial ryegrass, the higher DM and water-soluble carbohydrate content of the grass makes fermentation easier in the clamp.
New generation red clovers
Red clover has suffered in the past from its relatively short persistency but Germinal’s new generation red clovers, including AberClaret, can last at least four to five years in a cutting sward.
Our research and innovation team, Germinal Horizon, continues to innovate in this area, working to produce varieties with a lower crown. This will help make red clover more grazing tolerant and resilient to damage.
For more information on growing and managing red clover, read our 5 top tips for sowing red clover seed.
Ask an expert about red clover silage
Contact our grass and forage specialists if you have any questions about red clover silage.