In ideal conditions, most grass seed species will begin to grow in about 8-10 days after initial sowing. After 6-8 weeks, the grass will be fully established and providing full coverage across the lawn with no patches.
Taking your seed growing conditions into account, when your grass is growing successfully around the 6-8 week mark, you are free to walk on it, play on it and enjoy it as much as you see fit.
Please be aware that the successful growth of your garden is subject to a few preparation requirements and aftercare activities that you need to keep in mind. If not, your grass could take longer to grow or the worst-case scenario – not grow at all.
Best Preparation to Help Grass Seed Grow
Four things should be considered when sowing grass seed and hoping for the very best outcome, these are:
- Weather and Soil conditions (the environment that the seed is trying to grow in)
- Sowing Method
- Type of Grass Seed
Weather and Soil Conditions
Sunshine, temperature and water are the primary ingredients that power the growth rate of your grass. Although even with all of these ingredients in place, your lawn can still fall foul to poor ground preparation and adverse/extreme weather conditions. These issues can cause delays in growth or completely prevent the seedling's ability to germinate.
Therefore, weather and soil conditions when the seed was sown are crucial to successful germination and rapid growth!
Ideal Weather for Germination
Most grass species will germinate between 8-10 degrees Celcius (and above). Should these temperatures be inconsistent and drop frequently, germination and establishment could take longer.
How do you know when conditions are perfect?
Ideally, grass seed should be sown when temperatures range between 8-10 degrees consistently for at least two weeks.
In the UK, this generally means the sowing season is from March – September. Always keep an eye on the weather forecast for frosts, snow, flooding or heatwaves. And when deciding when to sow, it is best to consult a two-week forecast.
Ideal Soil/Sowing Conditions
The ideal seedbed should be free from weeds and mosses, needs to be level and have adequate draining. If seedbed preparation fails on any of these fronts, the seeds may struggle to grow.
Similarly, if the seeds are sown incorrectly, they may not germinate. Seeds need heat, moisture and air provided by the soil, so if the seeds are too close to the surface – they won't benefit from the key things they need to germinate.
Be aware of burying the seeds too deep (unable to reach sunlight) or too close to the surface. Sowing at the incorrect rate (too close together or too scattered) will also cause growth issues.
To find out the best method for sowing grass seed, please read our detailed guide here.
The Type of Grass Seed
This seed offers extremely fast-growing, especially within the UK.
Various grass species germinate at different temperatures, which also equates to how long it takes the grass to grow fully. For example, perennial ryegrass is a cool season grass and only requires temperatures of 8-10 degrees consistently to germinate. Since the UK gets temperatures of 8-10 degrees during the sowing season (spring, summer, and early autumn), fast and efficient growth is easy to achieve.
Fescues require slightly warmer temperatures of 10 degrees plus to germinate. We usually hit these temperatures during mild spring and warm summer months in the UK and this helps speed up seed germination. However, temperatures in the UK usually get to 8-10 degrees a lot earlier and more consistently, making perennial ryegrass a relatively faster-growing seed option when compared with fescue.
Grass seed mixture
Grass seed mixtures are often a blend of multiple species. Most of our mixes contain blends of perennial ryegrass and fescues, except for a few specialist mixes for sports and shaded areas. We also have other specialist mixes of 100% perennial ryegrass or 100% fescue.
What is in your mix will dictate how fast it will grow. As stated before, perennial ryegrass grows faster than fescue – so if you want a fine bowling-green quality ornamental lawn (100% fescue), be prepared to wait a little bit longer, and be aware of the ideal growing conditions.
One of our most popular mixes, SUPERSTAR: Back Lawn, offers you the best of both worlds through its 80% perennial ryegrass content. This seed mix is fast-growing and hardwearing, whilst also containing 20% fescue that helps to give it a fine appearance.
So, you have sown your lawn in the ideal weather conditions in a perfect seedbed, with great seed and the ideal mix for what you need – how can you further guarantee its quick growth? One way to enhance growth would be to ensure your lawn gets watered evenly.
After sowing your grass seed, you should water your lawn once a day daily and deeply for the first few weeks. Avoiding watering when it rains, you will soon see the little green shoots begin to appear all across your lawn.
For more information about how to water your lawn post-sowing and to keep those little green shoots growing, read our top tips for watering your lawn.
So now that you know how long grass takes to grow, you can have a quick read over our guide that covers the burning question of When will my grass grow?