Renovating an old lawn – re-turfing or sowing new seed.

Creating a new lawn from an old one normally a couple of reasons for doing this, firstly the old lawn might become too mossy, this is often down to the soil pH becoming to acidic after a number of years being fed with acid or high nitrogen feeds causing the soil the pH to become llowered to such a degree that it suits moss growth rather than grass growth.
In this case you will need to add a dressing of garden lime to adjust the soil pH.
Secondly older lawn often becomes uneven and the easiest way to sort this problem is to re-create the lawn.
The first task is to kill the existing grass by smothering for 6 to 8 weeks with some landscaping weed sheeting pegged down with some wire or wooden pegs. It’s important to use a weed sheeting that does not allow any light through
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The other method is to kill the existing grass using Roundup weed killer applied from a watering can on a dry day. The weedkiller takes two weeks to work.
It’s important to kill the existing grass and weeks before cultivating the soil because it will make the soil a lot easier to work
Once the grass and weeds are dead you can rotovate with a rotavator or cultivator. Ideally it need to be a machine with a back box
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Ideally you only need to rotovate down to 25mm to 40mm any deeper will bring to the surface old weed seeds.
Next rake the area in a number of directions removing any large stones and to create the general levels required.
Now use a roller or your feet tread in the soil to compact it, then re-rake and repeat until you have the required levels – Now you are ready for sowing or laying new turf.
Before rotavating the area after killing the grass you need to consider any feeds that need to be added.
Nutrients – it’s a good idea to apply some Growmore fertilizer one handful spread over a square metre
Soil pH – if you need to raise the soil pH you should apply some garden lime
Grit sand – if you have a heavy clay soil before rotovating you can add some grit sand available from most builder merchants. The GardenAdvice team normally recommend a builders barrow full per 3 square metre