April 2025 Lawn Diary

This Month's Lawn in Brief

Following an unexpected return of winter weather that lingered into March, while some areas enjoyed pockets of sunshine, most of us experienced a mix of rain, occasional frosts, and even more snow in some places. But with April upon us, we can (fingers crossed!) start to leave winter behind and look forward to some gardening fun as warmer weather arrives.

Key Lawn Tasks: Now Through April

• Moss Control
• Fertilising
• Aeration (Spiking only)
• Raking or Light Scarifying
• Spot Weed Control only
• Top Dressing
• Repairs and Seeding

The Weather Outlook

Courtesy of the Met Office:

Monday 28th March - Wednesday 6th April: The end of March will be characterised by changeable weather patterns. This will see a mixture of showers or longer spells of rain, mainly in the north and northwest, interspersed with some dry and bright periods, especially in the south. Temperatures will mostly be near normal for the time of year. From early April, a good deal of settled weather is likely across the UK, with many areas remaining dry under clear or sunny spells and experiencing light winds. Periods of unsettled weather may sometimes develop, accompanied by rain outbreaks and strong winds. Temperatures will likely be close to normal overall, though cold are possible where clear skies coincide with light winds

Monday, 7th April – Monday, 21st April: Slow-moving (or blocked) weather patterns are most probable during the middle of April. Low and high-pressure areas will be near the UK, and their placement can result in either dry conditions or wetter episodes with rain or showers. Temperatures will vary, with some large day-to-day swings possible, but they are likely to be near average overall.

Did Your Lawn Struggle in Last Summer's Drought?

Our inbox suggests many lawns weren't in great shape and couldn't be fully restored before winter. To help you breathe new life into your lawn and get it looking fantastic again quickly, head to our Lawn Trends section for advice on using a wetting agent as a preventative measure in our article How to Stop My Lawn Drying Out.

What's New in Lawn Care?

In our new Lawn Care Problems section, we've added many new articles to help you care for your lawn. These cover a wide range of standard and less common issues and questions you ask us regularly.

Lawn Trends

Check out our Lawn Trends area's most essential and up-to-date seasonal articles.

Mowing the Lawn

If you haven't made a first cut yet, try to do so soon, as April can be a warmer, wetter month, which will accelerate growth but make mowing more challenging. Keep the mowing height on the higher side until May unless you're raking or scarifying, in which case a lower cut is necessary.

Early Mowing Tips:

• Mow in the afternoon to allow the grass to dry during the day.
• Keep the cut higher until you establish a more regular mowing routine.
• Be careful when turning, as the ground may be soft.
• Thoroughly clean the mower – wet grass sticks easily!

Mowers

For the mowing season, there are two essentials: keep your mower clean and keep the blades sharp. Starting the spring with sharp blades is ideal but often rare! Damp grass can quickly build up inside the mower, so brush, scrape, or hose it thoroughly after each use. Secondly, if you mow frequently, be prepared to sharpen or replace your blades mid-year to maintain a clean cut. Consider ordering a spare blade now before they sell out!

Fertilising the Lawn

Now is the perfect time to apply spring lawn feed. The demands of winter will have taken their toll, and a spring feed is crucial for a healthy lawn. The best timing for this will depend on how the weather in your area is warming up. If you're performing lawn maintenance tasks like moss control and raking or scarifying, apply your lawn fertiliser afterwards. Weed control should follow fertilising, ideally in May or even June.

Various Lawnsmith fertilisers are suitable for application at this time of year. Your choice depends on your soil type and your lawn care enthusiasm.

FAQ: What Fertiliser Should You Use When Overseeding an Existing Lawn?

Typically, you use the fertiliser that is appropriate for your soil type. However, you must support the new seedlings and your established lawn when overseeding. In this case, use a neutral fertiliser, such as Spring & Summer Natur, or one of the Lawnsmith fertilisers designed for sandy soil. These fertilisers have a wider range of nutrients suitable for young and mature grasses.

Weed Control

Common weeds like dandelions will appear quickly as temperatures rise, while Woodrush and Celandine are already visible. Digging them out is the most reliable method of control. See Weed Identification for more details and control methods.

Avoid applying weed killer to the entire lawn, as many more weeds will emerge over the next month. Treat individual weeds with a ready-to-use weed killer or manually remove any large, obvious weeds. If there are too many weeds, treat the whole lawn towards the end of April or into May, about two or more weeks after fertilising.

Moss Control

This winter has been wet and dull, so moss is likely prevalent. This is where a significant portion of your effort should be directed if your lawn has extensive moss infestations. If you've been following our Moss Control Advice and the Lawn Diary, you'll be updated with your lawn care program. Last month, we added an article to Lawn Care Advice based on nationwide feedback confirming serious moss problems and significant grass thinning. Here's the link if you missed it: Spring Lawn Repairs.

This month is ideal for tackling moss, as the grass will soon grow strongly. If you're applying a ferrous sulphate-based moss killer, you can do so more quickly, but only after mowing the lawn to a medium to high cut. This means you won't need to mow for a while after application, and you'll expose some moss for better treatment access.

If you're planning to rake out the moss, your plan should include applying an iron or ferrous sulphate-based moss killer, overseeding bare patches or the whole lawn with appropriate grass seed, and aiding recovery with fertiliser. Raking in early May is acceptable, provided sufficient ground moisture for grass recovery.

Remember, you mustn't kill the moss before raking it out. Applying a ferrous sulphate-based moss killer after raking will be more effective on any remaining moss. Treating before and after is even more effective, especially if moss thrives in your lawn. However, allow at least three to four weeks between applications in cool, wet conditions. See Moss Removal.

A chemical-free product will be available shortly after treatment for those concerned about the safety of children and pets on the lawn. See MossOff

TIP: Good moisture levels around the grass and moss, such as on a dewy morning, help ferrous sulphate penetrate deeper. If there's no dew and the moss is dry, lightly sprinkle the lawn with a sprinkler. It only needs a slight dampening.

Watering the Lawn

Water the lawn only if you've sown grass seed or laid turf, if moss needs a little wetting before spraying with ferrous sulphate, or if it is dry after raking or scarifying.

Aeration & De-compaction

Any form of lawn aeration is generally recommended in April. This can be slitting, spiking, or hollow tining. If you're using a hollow-tine aerator, do it sooner rather than later, as the large holes help the lawn warm up and drain. This can be problematic if the weather becomes warm and dry, causing the lawn to lose too much water. My cut-off for hollow-tine aeration here in Yorkshire is mid-to-late April, so if you're in southern England, early to mid-April and perhaps early May for Scotland.

As discussed in Lawn Aeration Advice, aeration is highly beneficial when done correctly. It is relatively easy to use lawn aerators, such as a rolling aerator or aerator sandals. At a minimum, use a hollow-tine fork in high-traffic areas around clotheslines, path-to-lawn entry points, children's play areas, and the postman's shortcut. Add grass seed to worn areas after aeration, then fertilise the lawn.

Raking & Scarifying

This is the perfect time to use a lawn or manual raker scarifier to remove old, dry grass or moss. Remember that raking uses wire tines, while scarifying uses blades. This means raking is unlikely to cause much damage, whereas scarifying if done hastily, will cause damage as weeds become numerous. If possible, use spring for raking and light scarifying, with autumn being the best time for thorough scarifying and de-thatching. If the lawn is thin or has bare patches, especially if moss is a problem, consider getting some grass seed before weeds take hold. You can learn to do this correctly by oversowing with new grass seed.

Repairs & Renovations

All lawn repair and renovation jobs can now be completed. If you plan to turf, this marks the end of the turfing period. Turf laid after this month will require regular watering to establish itself.

Pests & Diseases

Early spring is often a disease-free time for lawns, with red thread usually appearing from May onward as humidity increases. Your main problem this month will be worm casts.

Worms

Though it's best to treat for worms at the first sign, they'll continue to surface throughout the winter, producing muddy casts that cause mowing problems in the spring. Worms are beneficial as they digest organic matter, provide nutrients, and enrich the soil. They also provide valuable aeration. A lawn with worms is generally much healthier than one without. Although only moderately reliable, we still believe that Ferrous Sulphate is the most cost-effective way to reduce worm casting.

Rolling the Lawn

Consider this for the finest lawns to consolidate areas raised by worm activity and frost heave. Roll your lawn from now into May on relatively firm ground (not soft). Note that rolling won't level a lawn; top dressing will.

Top Dressing

Top dressing is an advanced lawn care procedure that reduces thatch and smoothens the lawn's surface. If you're not a lawn enthusiast, it's best to skip this!

If you are, then lower the mowing height once you have good grass growth before applying your first top dressing. Application rates and frequency will vary depending on your goals and lawn type, so please read our top-dressing advice.

The New Lawn

This is an excellent time to create a new lawn with grass seed or turf. With warmer temperatures on the horizon, the seed will germinate quickly. Sowing seed or laying turf now, ideally with the help of spring showers, is an opportunity not to be missed.

Thanks for reading the Lawn Diary! Have a great month.