How to Start a New Lawn from Seed

Starting a lawn from seed is more affordable than turf and gives you complete control over grass variety. It takes longer to establish than turf, but with proper preparation and aftercare, you’ll have a lawn that’s perfectly suited to your garden’s conditions.

Here’s how to create a beautiful lawn from seed, step by step.

When to Sow a New Lawn

Timing is crucial for success. Grass seed needs warmth and moisture to germinate, and your new lawn needs time to establish before challenging weather arrives.

Autumn (September to mid-October) – Best time

Autumn provides ideal conditions: warm soil from summer, cooling air temperatures, and reliable rainfall. Your new lawn establishes roots before winter and comes back strongly in spring. Use Autumn Lawn Seed for best results in these conditions.

Spring (mid-March to May) – Second best

Spring works well but brings more weed competition (weeds germinate alongside your grass). The advantage is that your lawn has the whole growing season ahead to mature. Use Spring Lawn Seed which germinates reliably in cooler spring soil. If you’re starting a new lawn in spring, our spring lawn care checklist walks you through everything else your garden needs that season, from feeding to mowing schedules.

Avoid summer and winter

Summer heat and drought stress new seedlings, while winter temperatures prevent germination. Stick to spring or autumn.

Preparing the Site

Good soil preparation is the foundation of a successful lawn. Rush this stage and you’ll struggle for years. Do it properly and everything else becomes easier.

If you’re renovating an existing lawn that’s suffered over winter rather than starting completely from scratch, our guide to preparing your lawn for spring after winter damage covers a less intensive recovery process.

Step 1: Clear the area

Remove all existing vegetation, debris, rocks, and rubble. If there’s an old lawn, either strip it off with a turf cutter or kill it with glyphosate weedkiller (wait the recommended period before proceeding, typically 2 to 4 weeks).

Remove any perennial weeds like dandelions, docks, or bindweed completely, roots and all. These will cause problems later if left.

Step 2: Dig or rotavate

Break up the soil to a depth of at least 15 to 20cm. For small areas, double digging with a spade works. For larger areas, hire a rotavator. It’s much faster and less back-breaking.

As you dig, remove any large stones, roots, or debris you encounter. Break up any large clods of soil.

Step 3: Improve the soil (if needed)

This is your one chance to improve the soil structure before the lawn goes in:

• Heavy clay soil: Work in sharp sand and organic matter to improve drainage
• Sandy soil: Add organic matter to improve water retention
• Poor soil: Incorporate well-rotted compost or quality topsoil

Most UK garden soils benefit from some organic matter being worked in. It improves structure, drainage, and nutrient-holding capacity.

Step 4: Level and firm

Rake the soil to create a rough level. Then firm it by walking over the entire area with your weight on your heels (the “gardener’s shuffle”) or use a roller. This reveals low spots that you can then fill and re-firm.

The goal is firm but not compacted soil. You should be able to walk on it without sinking in, but it shouldn’t be rock hard.

Step 5: Create the final tilth

Rake the surface to create a fine, crumbly seedbed. Remove any remaining stones larger than about 2cm. The surface should be level with a fine texture, like breadcrumbs rather than lumps.

Let the soil settle for a week or two if possible. This allows any weed seeds near the surface to germinate, and you can then hoe them off before sowing.

Sowing the Seed

Apply pre-seed fertiliser

Before sowing, apply pre-seed fertiliser according to the pack instructions. This provides phosphorus for root development, which is essential for new seedlings. Rake it lightly into the surface.

Calculate your seed quantity

For a new lawn, use approximately 35 to 50g of seed per square metre. Here’s a quick guide:

• 25m² (5m x 5m): 875g to 1.25kg
• 50m²: 1.75 to 2.5kg
• 100m²: 3.5 to 5kg
• 200m²: 7 to 10kg

It’s better to slightly over-seed than under-seed. Thin areas are harder to fix later than a slightly dense initial sowing.

Sow evenly

Divide your seed in half. Sow the first half walking in one direction across the lawn, then sow the second half walking at right angles to the first. This cross-pattern ensures even coverage.

For larger areas, a handheld broadcast spreader makes this easier and more consistent than hand broadcasting.

Rake in lightly

Gently rake over the surface to work the seed into the top 5 to 10mm of soil. You’re not burying it deeply, just ensuring good soil contact. Some seed will still be visible on the surface, which is fine.

Firm the surface

Lightly roll or tread the area to press the seed into contact with the soil. Good seed-to-soil contact is essential for germination.

Watering and Aftercare

Initial watering

Water the area thoroughly but gently after sowing. Use a fine spray. You don’t want to wash the seed away or create channels in the surface.

Keep consistently moist

The seedbed must stay moist until the grass is established. This typically means watering lightly every day or two in dry weather for 2 to 3 weeks.

The critical rule: once germination starts, the seedbed must not dry out. Seedlings that dry out die. In warm, dry conditions, you may need to water twice daily.

Protect from birds

Birds love grass seed. Cover the area with netting or use bird-deterrent tape if birds are a problem in your garden. Remove once the grass is established.

First Mow and Beyond

When to first mow

Grass typically germinates in 7 to 21 days depending on variety and conditions. Wait until it reaches about 5 to 7cm tall before the first mow.

For the first cut, set your mower to its highest setting (around 4 to 5cm). Ensure the blade is sharp. New grass pulls out easily if torn rather than cut cleanly. Remove no more than the top third of growth.

Subsequent mowing

Gradually reduce the cutting height over several mows until you reach your desired height (typically 3 to 4cm for most lawns). Mow regularly once the lawn is established, weekly during the growing season.

Stay off the lawn

Keep foot traffic to a minimum for at least 6 to 8 weeks while roots establish. Light walking for mowing is fine after 4 weeks, but avoid heavy use or playing on the lawn.

First feed

Wait until the lawn has been mowed 3 to 4 times before applying regular lawn feed. Then follow a seasonal feeding programme to keep your new lawn healthy.

Once your new lawn is established (typically 6 to 8 weeks after sowing), a seasonal lawn treatment provides the balanced nutrition it needs to thicken up and resist weeds. For year-round care without the guesswork, the Year Round Lawn Treatment Bundle covers every feed from spring through winter.

Weed control

Some weeds are inevitable in a new lawn. They germinate from seeds already in the soil. Don’t panic. Most annual weeds will disappear with regular mowing. Wait until the lawn has been mowed at least 4 to 5 times before considering any weed treatment, and avoid weedkiller in the first full growing season if possible.

Choosing the Right Seed

Different seed types suit different situations. For a detailed comparison of every option with a decision table to help you pick, see our best grass seed UK buyer guide.

Fast Growing Grass Seed: Establishes quickly. Ideal if you want results fast or are sowing later in the season.

Autumn Lawn Seed: Formulated for autumn sowing conditions. Establishes strong roots before winter.

Spring Lawn Seed: Germinates reliably in cooler spring soil. Gets growing quickly once temperatures rise.

Shade Tolerant Grass Seed: For areas under trees or beside buildings where light levels are low.

Luxury Grass Seed: Fine-leaved varieties for the best appearance. Ideal for front lawns or show gardens.

Seed vs Turf: Which Is Better?

Choose seed if:

• Budget is a priority (seed costs a fraction of turf)
• You want a specific grass variety
• You have time to wait for establishment
• The area is awkwardly shaped (seed fills any space)
• Access is difficult (seed is much easier to carry)

Choose turf if:

• You need instant results
• You’re sowing at a less ideal time of year
• Weed competition is severe
• You need to use the lawn quickly

For more seeding guides and lawn care advice, visit our UK lawn care resource.

Frequently Asked Questions

How long until my new lawn is usable?

Light use (walking) is typically fine after 6 to 8 weeks. More vigorous use (children playing, garden parties) should wait 3 to 4 months. A full growing season produces a mature, resilient lawn.

What if germination is patchy?

Some patchiness is normal. Once the main lawn is established, overseed any thin areas. This is easier than trying to fix problems in the initial sowing.

Can I sow grass seed in shade?

Yes, but use shade-tolerant varieties. Even shade-tolerant grass needs some light. If an area gets less than 3 to 4 hours of light daily, consider alternatives like ground cover plants.

Do I need to use topsoil?

Only if your existing soil is very poor, heavily compacted, or full of rubble. Most garden soils just need organic matter worked in. If you do bring in topsoil, ensure it’s quality screened topsoil, not subsoil.

What if it doesn’t rain after sowing?

You’ll need to water. A new lawn from seed is a commitment to watering for 2 to 3 weeks minimum. If you can’t water regularly, wait for a wetter time of year or choose turf instead.