Clover is one of the most common lawn weeds, and once it takes root, it can be very tricky to get rid of. So, preventing it from growing in the first place is the best way to control clover.
A lush green lawn puts a smile on many a gardener’s face. When clover and other weeds spread, they can spoil this perfect sight. Although their cute little flowers attract bees and other pollinators, clover competes with grasses and other lawn plants. And while keeping the pollinators happy keeps us happy, this can soon become problematic if someone is stung while playing on or walking across the lawn. To help prevent clover from taking over your lawn, we have put together some helpful tips for you below.
Clover in lawns: what is the cause?
A sparse or patchy lawn leaves room for clover to settle in. Clover plants reproduce either by seed or spreading roots and need very little to thrive. Lawn grasses, on the other hand, are quite particular about their growing conditions and, if not given the right care, will display stunted growth and be less competitive against invasive weeds.
Site conditions: These play a key role in preventing clover growth. Grass requires sufficient light alongside a loose and well-aerated soil, such as a sandy loam soil. Clover, however, tends to grow in “poor” soil. Therefore, good soil preparation before sowing the lawn is the first step in clover prevention.
Cutting the lawn too short: Cutting the lawn too short damages lawn grasses and allows light to reach the creeping shoots of clover, encouraging its growth. Making mistakes when mowing the lawn is easier than you may think.
Not enough fertiliser: Clover has a special relationship with a bacteria called rhizobia that helps it get nitrogen from the air. This gives clover a real advantage over lawns in nutrient-poor soil. Only a well-fertilised lawn can stand up to clover.
Now the question remains: how does clover get onto the lawn in the first place? Roots and seeds are often already present in the soil before the lawn is sown. Wind and animals, too, play a large part in spreading clover seeds.
Once clover has started to grow, removing it is very difficult. Here are some tips on how to prevent and reduce clover in lawns.
How to get rid of white clover in the lawn
The perennial white clover (Trifolium repens) pops up between May and October with its bushy white and pale pink flowers. It spreads quickly and is the most common species on UK lawns.
White clover grows in soil with pH levels from neutral to alkaline. So, using lime against white clover in the lawn is ineffective. Instead, lawn fertilisation is the answer. Unlike lawn grasses, clover is adapted to growing in nitrogen-poor soils, but needs a comparatively high amount of phosphate. Our Plantura Lawn Feed ensures an optimal nutrient supply to the lawn and does not support weed growth − it contains a lot of nitrogen and potassium and only a small amount of phosphate.
White clover should never be scarified, as this will only make it spread further into the lawn. Instead, use a spade to dig out individual plants. Dig deep to make sure you get all the roots out.
Covering white clover with a light-excluding sheet for about eight weeks in the summer can eliminate it from larger areas. Just remember to reseed the lawn afterwards.
With a growth height of 5 to 20 cm – some flowers even up to 30 cm high! − the blades of a lawn mower can easily cut and, thus, weaken white clover. However, take care not to cut the grass too short.
Overview: White clover
- Add fertiliser
- Dig out white clover plants
- Mow white clover to weaken it
- Cover the affected areas
Getting rid of red clover in the lawn
From April to October, the deep-rooted perennial red clover (Trifolium pratense) brings a touch of colour to lawns with its purple flowers. It thrives in similar conditions as white clover. So to control it, you can use the same methods of using nitrogen-rich and phosphate-poor fertiliser, digging out individual plants and covering them with a light-excluding material. Red clover not only has deep roots, requiring deeper digging for removal, but it also grows quite tall to anywhere from 15 to 80 cm. It can easily be kept short with a lawn mower. Take care not to cut the entire area too short though, as this will weaken the lawn and make it easier for the red clover to reproduce and spread further. A good cutting length is 4 to 5 cm.
Overview: Red clover
- Add fertiliser
- Dig out red clover plants
- Mow red clover to weaken it
- Cover the affected areas
How to get rid of wood sorrel
Wood sorrel is a clover-like weed with yellow flowers that is often mistaken for clover. Not only does it look similar, but it too is a common nuisance in lawns. Creeping wood sorrel (Oxalis corniculata) is not so problematic − it is an annual and does not spread through its roots. Common wood sorrel (Oxalis acetosella), on the other hand, is a perennial and survives with the help of its creeping rhizomes.
Preventing wood sorrel is a bit different from clover, and the methods also differ for each wood sorrel species.
Liming: What all species of sorrel have in common is that they like to grow in nutrient-rich, humus-rich and acidic soil. With a fast-acting garden lime, you can lower the pH value of your soil. Neutralising the natural acids in the soil makes your lawn a little less appealing to wood sorrel. Adding lime also increases the activity of microorganisms, which can increase soil fertility. Before liming your lawn, we recommend carrying out a pH test to make sure you apply the right amount of lime.
Weed pruner: With the help of a weed pruner, you can remove all types of wood sorrel with very little effort. Be sure to pull out the entire taproot, otherwise the plant will grow back.
Scarifying: For some wood sorrel species, scarifying is a proven method for removal. But that is not the case with common wood sorrel (Oxalis acetosella) and yellow wood sorrel (Oxalis stricta). Both grow through rhizomes, and scarifying these species would only encourage them to spread even more. However, for many other annual wood sorrel species, such as creeping wood sorrel (Oxalis corniculata), scarifying can indeed eliminate them.
When scarifying a patch of lawn, the entirety of the weeds in the affected area must be removed, roots and all. It is important to reseed the lawn afterwards to repair bare patches. As wood sorrel is partial to shade, reseeding with shade-tolerant lawn seed is recommended. Shady lawn seed is adapted to the requirements of shady places of the garden and can therefore successfully compete against unwanted weeds.
Digging out: If you don’t have a scarifier or dethatcher at hand, you can also use a spade. Don’t forget to reseed the area afterwards.
Covering: Using a lawn mower against wood sorrel will accomplish very little as the plant’s growth height is too low. Instead, place a light-excluding sheet over the affected area, weighing it down so that it does not blow away. After about six to eight weeks the clover should be dead. Of course, the lawn will also be affected by the lack of light, but it recovers much faster than the wood sorrel.
Reseeding: In the case of stubborn wood sorrel species, there is usually no choice but to remove the whole top layer of soil and reseed the lawn, especially if it is a perennial. While preparing the soil for reseeding, it is important to meticulously remove every root fragment. Then, be sure to leave the area fallow for at least two weeks before reseeding the lawn − this time will allow you to spot any missed root fragments trying to sprout anew. Remove any sprouting plants before sowing the lawn.
Overview: Wood sorrel removal
- Add lime
- Scarify the affected area
- Dig out wood sorrel plants
- Cover the affected areas
- Reseed for new lawn growth
Preventing clover and wood sorrel in your lawn
Prevention is the best strategy when it comes to tackling clover in lawns. Here’s what you should consider if you don’t want clover in your lawn:
Fertilise: As mentioned, a good supply of nutrients is the key to controlling and preventing clover in lawns. A fertiliser high in nitrogen and low in phosphate, such as our Plantura Lawn Feed, is extremely effective.
Soil: Before sowing a lawn, it is best to ensure that the soil is loose, not too clayey and well aerated. To improve a heavy soil, work some sand into the top layer. It is also possible to scarify and sand an existing lawn, especially if the soil is quite clay-rich and heavy. Scarifying should only be repeated every few years − when done too frequently, scarifying inhibits grass growth.
Watering: Lawn grasses are less drought tolerant than the most clover plants. So, it is important to water the lawn correctly. It is a good idea to find out what type of lawn grasses you have in order to learn how best to water your lawn.
Pruning: Regularly mowing the lawn encourages the grasses to branch out and create a dense surface. This reduces the risk of clover taking root.
Lime: To repel wood sorrel, keep your soil slightly acidic to neutral − if the soil is too acidic, wood sorrel will flourish. We recommend doing a pH test on the soil to check the acidity level and find out how much lime you need to apply. If the pH test shows that the soil is too acidic, try applying a fast-acting lime.
The right grass seed: Wood sorrel species love the shade. Unfortunately, this is not true for most lawn seed mixtures. Therefore, it is important to get the right grass seed mixture for shady lawns to prevent wood sorrel.
Summary: Clover and wood sorrel prevention
- Mix sand into heavy soil
- Scarify every few years
- Fertilise well
- Water appropriately
- Mow weekly
- Apply lime as needed
- Use shade grass seed mixtures for shaded areas