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How to sow a new lawn from seed


Sowing a new lawn from seed is a great way of creating a cost effective lawn, but it important to consider the time of year you are doing it, carry out correct preparation and be patient as the lawn establishes over several months.

Lawn Seeding can be done by professional contractors such as Lawntechs’ sister company Hewlett Turf & Landscapes or you can do it yourself with a little time and effort.


Autumn is the best time to sown grass seed, (Mid August-October), whilst the soil is warm and damp which will assist speedy germination. Spring is the second best time, (April-May), but germination will be slower as the soil is cooler and there are disadvantages such as competition from weeds and dry weather as you move into the summer.

Tools & materials you will need: Rotovator, Garden fork, garden spade, shovel, wheelbarrow, soil rake, pre-seed fertiliser, grass seed, weed killer, weed killer applicator, sprinkler, garden hose.

Step 1 (to be done well in advance) – Kill Existing Vegetation: Kill off any vegetation such as weeds and grass with Glyphosate herbicide or similar systemic herbicide or thoroughly did out vegetation, or cover the area with a black plastic sheet several months prior. This will make life much easier for rotovating and will prevent unwanted weeds growing through the new turf.


Step 2 – Rotovate: Rotovate or dig through the area to a depth of approximately 100mm deep to relive compaction and to create a workable tilth. Several passes with a rotovator may be necessary.

Step 3 – Raking: Rake the soil down to create a fine smooth tilth to remove stones and particles which are larger than 20mm in size. Firm in the soil by treading up and down the area in between passes with the rake. Scrape off high points and fill in low areas with a shovel. Carry out final tilth with a finer rake. Contractors may use powered rakes and other specialist machinery. Remove all arising’s such as stones and debris from site. Remember it is crucial to get the soil as smooth and even as you want the final lawn to be. Always bring soil right up to the same level as any adjoining paving or edgings.

Step 4Fertiliser: Apply pre-turf/seed fertiliser @ 35 grams per square metre.

Lawnstore Organic Pre-seed fert

Step 5 – Sow Seed: There are various ways to sow lawn seed. The main thing is to ensure the seed is spread at the correct rate, usually 25-35gramms per square metre, evenly over the area and that the seed has good soil contact. If you do not have an applicator or seed sowing drill as used by professionals simply spread the seed by hand evenly over the area at 30-35 grams per square metre and lightly rake-in.

Step 6 – Watering: For best results newly sown seed must always remain moist and unless conditions are naturally damp. Water once twice per day for approximately 3-4 weeks depending on weather. Once germination occurs reduce watering unless conditions are very dry.

Step 7– First mow: Carry out the first mow on a high setting approximately 4-8 weeks after germination or once the new grass is about 2-3 inches long. The new seed will gradually thicken up and fill in over several months.

Step 8 – Aftercare

The new grass will gradually thicken up and fill in over several months. 70-80% of weeds tend to die off with regular mowing. Stubborn perennial weeds can be killed off with a selective herbicide after about 3 months or once the grass has matured to the 3 leaf stage. A gentle fertiliser programme using Lawn Store semi organic fertiliser will help the lawn to establish and keep it thick and healthy.

Sowing a new lawn from seed is a great way of creating a cost effective lawn here is some advice to get you started.

How to control weeds in a newly seeded lawn

How to control weeds in a newly seeded lawn

However, you can get rid of these weeds just as fast as they have appeared.
The important thing to remember when new weeds appear in your newly sown lawn is not to act hastily – do not apply a Feed, Weed and Moss Killer type product of any kind on a newly sown lawn.

Although this can be frustrating and we can appreciate that a quick solution will be desired, the good news about these types of weeds is that they are largely shallow rooting and should come out with the first mow at the 6-8 week mark after sowing. If they don’t, they should be easy to pull out of the turf.

If you find that the weeds are recurring past the 6-8-week mark, you may wish to consider using a selective herbicide to spot spray your weeds. Some weed killers such as glyphosate (Roundup) kill more than just weeds, so it is important to not apply these as if they are not done precisely, they can kill your grass. Shop bought selective weed killers will recommend when to apply their product and how often and you should read the instructions thoroughly and adhere to them.

In short, here’s what you should do if you encounter weeds in your newly seeded lawn:

  1. Don’t panic – don’t use a Feed, Weed and Moss Killer product on a new lawn
  2. These weeds will be shallow rooting, you can pull them out by hand or wait until the 6-8 week mark to mow them out
  3. If the weeds are persistent and reoccurring, use a selective herbicide to spot treat them

If you find that when the lawn is at least six months old and has been taken over by weeds or moss, you can use a Feed, Weed and Moss Killer product.

When your new grass starts to grow, it can be quite alarming when weeds start to grow with it. Sometimes, despite the most thorough seedbed preparation, weeds can lay dormant in soil until the conditions are made perfect for them to make an appearance – such as a reseed.