Have you ever looked out at your lawn and noticed it’s looking a little wilted? It might need a little pick-me-up: fertiliser. Grass is essentially hundreds of hungry little plants that need regular feeding so they have the energy to grow.
There are two key times to fertilise your lawn: spring and autumn. For liquid fertiliser, all you need to do is hook the bottle up to your garden hose and spray. Granular fertiliser, on the other hand, will need a spreader for even distribution. Then you water it down so the ground can absorb the nutrients.
Perk up your lawn with some food for healthy, green grass. Here’s how to fertilise a lawn – and some other tips to keep in mind!
Why Fertilise a Lawn?
Fertilisers provide essential nutrients for an established lawn, encouraging healthy growth and grass throughout the year. Grass does get its food from the sun and soil, but the nutrients in the soil diminish over time. Using fertiliser gives your soil a nutrient boost.
If you notice less grass growth, sparse grass, or pale grass, those are symptoms of poor lawn nutrition. Correct this nutrient imbalance by applying fertiliser to manage your turf.
Fertilising is also a good way to control weeds, moss, and disease on your lawn. It improves grass recovery and keeps the turf green and lush. You’ll also save more money since fertilising reduces the need for turf replacement or re-seeding.
When to Fertilise Your Lawn
Lawns, like most plants, move with the seasons. Grass comes out of hibernation in early spring, then continues growing throughout the year until it starts to slow down in late autumn.
When to fertilise your lawn? You should be doing it at least twice a year – spring and autumn. Mid-summer is optional but might help improve colour and resilience.
SPRING: Fertilise the whole lawn once the grass has resumed growth, typically once temperatures are above 10ºC.
MID-SUMMER: You can use a quick-release fertiliser to give your lawn a boost for a few weeks.
AUTUMN: Wait for the weather to start turning, and get rid of any dead grass before applying the food. You can also use slow-release fertilisers in late autumn that will slowly feed your lawn over winter.
How Often to Fertilise Your Lawn
Check the feed duration of your chosen fertiliser. Most slow-release fertilisers take between 14–16 weeks to fully exhaust, while quick-release formulas take 4–6 weeks and may need reapplication.
Types of Lawn Fertiliser
There are several kinds of lawn fertiliser available on the market. Each has its own advantages and application methods, so keep those in mind while deciding which to use on your lawn!
1. Liquid fertiliser
It’s all in the name – this is a liquid formula that feeds straight into the blades of grass. There’s less runoff from watering or rainfall, and less of it gets into the soil. This absorbs more quickly into the grass, but may need more frequent reapplication.
2. Granular fertiliser
This comes in the form of pellets of fertiliser formula. Granular fertilisers often contain NPK (nitrogen, phosphorus, potassium) and organic matter. This form provides a slow nutritional boost and improves the soil’s nutrient profile. However, it’s more tedious to apply and requires a wetting agent.
3. 3-in-1 Fertiliser
This formulation combines three lawn care processes in one – fertiliser, weed killer, and moss killer. You should only use 3-in-1 fertiliser on established lawns, not a new lawn.
How to Fertilise a Lawn
Fertilising is part of proper lawn care! Learn how to fertilise your lawn properly so you can keep it healthy and thriving.
1. Before fertilising your lawn
Perform necessary lawn maintenance tasks before you apply fertiliser. Mow 1–2 days ahead of time, remove any weeds, and aerate your lawn. This will all help the fertiliser absorb better.
If you need help prepping your lawn, get a lawn care service to help you out!
2. How to use granular fertilisers
To ensure even coverage, use a fertiliser spreader. Check the packaging for the suggested spreading rate, and try to work on an overcast day or in the late afternoon/early evening.
Once you’ve applied the granules, water off the fertiliser from the grass to prevent burn damage. Do this after application and again the next day, then water regularly for the next 3 weeks to supplement the growth.
3. How to use liquid fertilisers
Lawn Fertilising FAQs
Need to know more about lawn fertilising? Here are some common questions you might have.
1. Slow-release fertiliser vs quick-release fertiliser
Slow-release fertilisers take longer to work but give you longer coverage – about 14-16 weeks. This means you need to do less maintenance and can go for long periods of time between applications.
Quick-release formulas give you faster results since they absorb more quickly into the ground. However, they have a much shorter coverage – typically 4–6 weeks – and need more frequent applications.
2. What is NPK?
NPK is a common lawn care acronym for Nitrogen, Phosphorus, and Potassium. Your fertiliser’s NPK ratio is the percentage of each element in the product.
Nitrogen maintains green grass and helps with disease.
Phosphorus promotes healthy roots for improved drought tolerance.
Potassium strengthens your plant against extreme conditions.
The fertiliser you buy should have the appropriate NPK ratio for your garden. This will depend on your soil pH and composition, so it’s good to test your soil before fertilising your lawn. This way, you’re not overloading on certain nutrients and causing a nutrient imbalance that could harm your plants.
3. Can you over-fertilise your lawn?
Yes – you can. Too much fertiliser causes “fertiliser burn,” which is when nitrogen and salt levels in the ground increase too rapidly. This can damage or even outright kill grass, resulting in dead patches or yellowed and browned strips.
Tips for Fertilising a Healthy Lawn
If you’re using granular formulas, water your lawn 2–4 days before application so that the ground is moist (not wet). Do not apply fertiliser to a lawn suffering moisture stress.
If you want to avoid using harsh chemicals on your lawn, look for organic or all-natural fertilisers! These are available in different forms and often contain organic matter.
There are many benefits to knowing how to fertilise a lawn, not least of which is keeping your grass healthy. Keep things green and growing with regular feeding – this way, everyone is happy!