Newly laid turf is in a vulnerable state due to recently having the bulk of it’s roots chopped off and then being taken out of the ground, rolled up and shipped to your back garden. Whilst grass is a hardy plant and is perfectly capable of living through this process, it does require a bit of delicacy at the start of it’s life as your new lawn to allow it to establish itself.
One of the key things that you can do as a gardener to ensure the lawn settles well is to mow the grass properly, and at the right times. In this article we are going to discuss when to cut new turf and the best procedure to follow for the first mowing.
The general advice is usually after around two weeks if laid in summer, and after around six weeks if laid in winter. However, the true answer to this question is more nuanced, and depends on a couple of variables. Most importantly the current weather and the type of grass you have used.
Almost all turf used in the UK is from cool season grasses, and these grasses grow fastest from late spring to early summer, and then again in Autumn.1 During these periods most new turf should be cut after around two weeks. Although some speciality grasses that grow particularly rapidly, such as Rolawn Medallion, can sometimes be cut as soon as two or three days after laying.2
During the winter growth will reduce greatly, sometimes even completely halting throughout especially cold temperatures. In this case the lawn may need to be left for up to six weeks before the first cut. In truth, it’s impossible to give an exact time frame for any particular time of the year because of variations in the weather and grass species. The most sure-fire method is to use your grasses actual growth to determine when to cut it. As a ballpark figure, you want the grass to have grown to a height of around 60mm before cutting.
By far the most important consideration before you go to cut your new lawn is whether or not the roots have firmly gripped the soil. If they have not, the blades of the mower will pull at the turf and can even rip it out of the ground, resetting any progress that the plant made to root itself. To ensure this doesn’t happen, it’s imperative that you first check that the turf has rooted.
This can be done very simply by lightly pulling upwards at one of the corners of your garden with your hand. If the turf comes up with the soil, it has not yet had time to root and so you should wait a few more days before testing again. On the other hand, if you feel resistance and the turf doesn’t easily come up, you can be confident that your lawn has established sufficient roots to be safely mowed for the first time.
One other thing to take into account is the type of mower that you will be using. Rotary mowers are slightly more stressful on the plant than cylinder mowers, and so firm roots are imperative if you are using one of these. Whereas cylinder mowers are much lighter on the root system, and so there will be less chance of doing damage to your new lawn.
The most important thing to keep in mind here is to not cut off too much at once as this can damage the grass. It’s impossible to do any harm by cutting too little off at a time, with some experts even suggesting that you can mow your lawn twice a day if you want to keep it really pristine.3 As a general rule, you should not cut more than a third of the height of the grass in one go, as this will put a lot of stress on the grass.
As well as this, you should try to avoid cutting the grass to a height of less than 20mm, unless it is a speciality breed that is better suited to a close shave. This number increases in winter when the plant becomes dormant and is more vulnerable, and we recommend keeping your lawn at a height of at least 30-40mm during this period.