Keep off the grass
Make sure to keep off your lawn whenever the grass is frozen, or the soil is overly wet or even waterlogged. Walking on frozen grass can damage its blades (leaves), leading to dead patches. Walking on a wet soil, especially if the lawn sits on clay, will make muddy patches where weeds and moss can establish and compress the soil, driving out essential air, leading to poor grass growing conditions, which can also encourage lawn moss.
To mow or not to mow
One question that often gets asked in our advisory service is when to stop mowing in autumn and when to start again in spring. The answer is usually – you don’t!
Grass grows at temperatures of 5C (41F) and above, and in mild winters it will just keep on growing. So, you may not have any excuses to put the mower away, except if the grass/soil is too wet and/or frozen! You should cut it whenever it’s growing, ideally aiming to tip the grass blades, and removing no more than one-third of its height at any one time. For most lawns, aim to keep the height in autumn and winter to around 4-5cm (1½-2in).
Casting worms can be very active during the winter, depositing their casts on the surface of the lawn. While the presence of worms is very beneficial, their casts aren’t. They make perfect seedbeds for weed seeds. So, brush them away whenever you can, and especially just before mowing. Once smeared by the mower, they can damage the grass and are even better seedbeds.
There’s no need to feed your lawn in winter. In fact, it’s not a great idea to do so. But, hopefully, you gave it a feed last autumn with an autumn lawn fertiliser. If you didn’t, make a date in your diary this and every year. An autumn feed will give the grass a good deep green colour and toughen it up for the onslaught of adverse autumn and winter weather, ensuring the lawn is ready to use earlier in spring.
Once March arrives, you can start feeding with a spring and summer lawn food, such as Richard’s Lawn Magic.
As weeds won’t be actively growing in the cold temperatures, chemical lawn weedkillers will have little or no effect in winter. So, don’t bother to apply one.
If lawn weeds are an issue, and the soil conditions are suitable, you can hand weed them. Using weed pullers and other manual lawn weeding tools will work well at this time of year. So, get outside, get some fresh air and start dealing with those pesky weeds.
Similarly to weeds, the vast majority of lawn moss killers are unlikely to have much or any effect on lawn moss at this time of year. Small patches could be treated with lawn sand, which may also help “burn” away some lawn weeds.
Just be aware that moss is a symptom of poor growing conditions and will always keep coming back unless you cure the underlying problem(s). Moss is always worse where the soil becomes waterlogged or is badly drained, if the lawn is in shade, or if the soil is extremely alkaline or acidic. If the lawn is on heavy clay/compacted soil that is airless (which is the most common reason), this will ensure moss thrives, but grass grows poorly.
Once, temperatures warm up in spring, get out there and start dealing with the moss. Richard’s “no rake” Moss Remover is the simple way to treat it.
Scarify and aerate
You’ll probably be pleased to hear that this isn’t a good time for those muscle-aching activities; scarifying to remove thatch and aerating to improve aeration. So, you can sit back and relax – until March comes around and then it’s all hands to the pumps – or spring-tine rake and hollow-tine aerator.
If you do find these activities a struggle to carry out, the good news is there are powered versions available that will make both jobs a doddle.
Waterlogging & flooding
Sadly, on compacted soils that don’t drain freely, the lawn can become waterlogged. And, especially in extreme conditions, in gardens close to rivers or where the water table is high, the lawn can flood. Neither are great for creating and maintaining a quality lawn; the excess water drives air out of the soil and, as roots need air to breathe, they die and the whole plant soon follows. And then moss takes over.
On small lawns or where the waterlogging isn’t extreme, hollow-tine aerating followed by applying a lawn topdressing, may help. In more extreme situations, you may need to dig out sumps at the lowest point(s) to help remove the excess water. These should be about 60-90cm (2-3ft) square and as deep as need be to allow water to drain away easily. Then fill with brick rubble, stones etc. Top off with gravel. You can then lay a planting membrane on top and cover over with soil and turf if situated in the lawn.
If you’d like to know more about lawn care, Geoff’s new book Grow Lawns, will be published in March 2024 – click here for more information.