How to sow grass seed

Plant grass seed and enjoy a new lawn

In many gardens, the lawn is a vital balancing element, the perfect backdrop to the more colourful flowering parts of the garden. Without it, mixed borders can seem messy and overwhelming, and subtle planting combinations just get lost in the crowd. Big or small, an expanse of green has a unifying effect, providing a visual link between the different elements of a garden.

How to sow grass seed

If you're looking to create a new lawn area, grass seed is a low-cost way to get some greenery into your garden. There are a range of grass types available.

Read on for step-by-step help on laying a new lawn from grass seed. Alternatively, if you're looking for speedy results, head over to our helpful guide on laying turf.

Planning your lawn

how to sow grass seed

For best results, lawn seed should be sown in spring (from March to May) or early autumn (September to mid October), when the soil is moist and warm.

Before laying a new lawn, take some time to think about the part it will play in your overall garden layout. Consider where people will walk, or if there are any obstacles that will get in the way of mowing.

Areas likely to be subjected to heavy wear and tear – such as access routes and shortcuts or children’s play areas – are better anticipated at the planning stage. If need be, place stepping stones within the lawn, and position children’s play equipment on an area of natural play bark instead.

Grass in fairly deep shade will always be patchy and prone to moss infestation. In such situations, consider substituting an area of chipped bark, or similar, instead.

Overhanging foliage from beds and borders will damage the edges of the lawn and make trimming with shears difficult. A hard edging between lawn and border not only helps avoid this, but if laid flush with the ground will do away with trimming edges completely – you just mow straight over the top.

Seed versus turf

When deciding whether to create a new lawn from seed or to lay turf, you will want to weigh up the advantages and disadvantages of the two methods.

 
  Advantages Disadvantages
Seed

Low cost
Greater choice of grass types available
Convenience – unlike turfing, sowing can be delayed if the weather is unexpectedly poor

Takes time to establish
Sowing can only be done in spring or early autumn
Slightly more site preparation is needed
Difficult to achieve neat outer edges

Turf

Instant results
Quick to establish
With watering, can be laid at any time of year
Easy to keep an exact line around edges

Significantly more expensive
Rolls of turf spoil quickly so need to be laid promptly
May be difficult to find matching seed for filling gaps
Shrinks in hot weather unless well watered

Choosing grass seed

how to sow grass seed

There’s a wide range of grass seed to choose from, according to what you want the end result to be. For a fine ornamental lawn, choose a seed mixture that doesn’t contain any coarse grasses, such as ryegrass. But for a lawn that will need to double up as a party venue or football pitch, or that will simply need to withstand regular use, the tougher and coarser grasses are a better option.

Shady and sunny areas may need different types of seed. However, the difference between two types of grass can look obvious. To make this less noticeable, you can seed the bridging area with a mixture of the two seeds.

 

How to sow grass seed

how to sow grass seed
Step 1:

Clear the ground of all stones, debris and weeds. If necessary, treat any stubborn weeds with a systemic (non-residual) weed killer – this will reduce the likelihood they'll reappear later. Dig over the entire site with a garden fork, mixing in top soil or a soil improver (if you need to) which will improve the condition of the soil. Break down any hard lumps by bashing them with the back of the fork.

If the area is prone to water-logging, work in plenty of sharp sand to help with drainage.

Powered cultivator

If you’re working across a large area, use a powered cultivator (also known as a rotavator) to make light-work of breaking-up the soil.


how to sow grass seed
Step 2:

Add some pre-turf and seed fertiliser at about half the recommended rate and continue to take out big stones and bits of old roots.

Use a garden rake to go over the ground to produce an even surface.

how to sow grass seeds
Step 3:

Firm the soil down by compressing it with the heels of your boots.

Be methodical – start at one end of the patch and trample the soil in a straight line across the end of the plot, then turn around and go back. Carry on shuffling over the earth until you've covered the whole area with footprints.

Then gently rake over your footprints. Keep filling in any hollows and remove any last lumps of root and debris until the ground is as even as possible.

Keep off the area until you are ready to start sowing seed.

how to sow grass seed
Step 4:

Choose a non-windy day to sow seed, otherwise the seed will end up everywhere but where you want it!

If spreading seed by hand, tie four 1 metre bamboo canes together with garden twine to form a square. Then hold in front of you and spread a measured quantity of seed within it. This will show you how densely you need to sow the seed.

Repeat until the entire area has been covered. If using a spreader, add the seed to the spreader and cover the area until it’s covered. As with all seeds, check the packaging instructions for the recommend rate of application.

Don’t be tempted to over-seed the area. This will not only cost more (in seed) but also cause the seeds to rot and die.

how to sow seeds
Step 5:

When you have sown over the entire area, lightly rake the surface to mix the seed into the soil. The seeds also need light to germinate so don’t rake it in too deeply.

how to sow grass seeds
Step 6:

Finish the sown area by going over it methodically with a light garden roller.

Step 7:

Water in the new seeds to start the germination. If you don’t have rain within 48 hours of sowing, give the area a good soaking with a lawn sprinkler. Be careful not to wash the seeds away or create puddles.

Water daily, for 7 to 10 days, until the seeds are established.

Keep off the grass

A new lawn needs plenty of time to establish itself – so the last thing you want is for people and animals to trample it or for birds to eat the seed. To prevent this, either crisscross the area with cotton, tied to regularly spaced canes pushed into the ground, or use fine-mesh netting fixed a few centimetres off the ground.


how to sow grass seeds

Step 8:

Continue regular watering of the new grass seedlings - especially if the weather is dry. While the seedlings are very tiny and delicate, water using a fine mist spray from a hose gun attachment (pictured) or sprinkler with a mist setting.

As they grow stronger, water with an ordinary sprinkler.

how to sow grass seed

Step 9:

Once the grass has grown to 5cm to 8cm high, it can have its first cut. Check that the lawnmower's blade is really sharp, otherwise the shoots will tear and lift out of the ground. Set your lawnmower to its highest setting, so that you only take off the tips for the first few months and collect, and dispose of, the clippings.

The lawn will look patchy at first, but after the first cut, the grass will be encouraged to grow and fill the gaps.

As the lawn thickens up, the cutting height can gradually be lowered. Even if weeds appear, don't apply weed killer for at least the first six months after sowing. Weeds can be removed by hand whilst your new lawn establishes.

For more tips on looking after your lawn, read How to keep grass looking green and healthy.