How often should I feed my lawn?

Feed 2-4 times per year: spring (March-April), early summer (June), late summer (August), and autumn (September-October). Use the right seasonal feed.

What is the difference between spring and autumn feed?

Spring/summer feeds are high in nitrogen for growth and greening. Autumn feeds are high in potassium and phosphorus to strengthen roots for winter.

Can I over-feed my lawn?

Yes. Over-feeding causes scorching (brown patches), excessive growth, thatch buildup, and environmental pollution. Always follow recommended rates.

Should I feed after mowing?

Wait 2-3 days after mowing before applying feed. Water in granular feed if rain is not expected within 48 hours.

What happens if I over-fertilise my lawn?

Over-feeding causes fertiliser burn: brown, scorched patches. If you spill concentrated feed, flood the area with water immediately. Always follow application rates carefully.

GardenCalcs.uk

Lawn Feed Calculator — How Much Fertiliser for My Lawn

Calculate the right amount of lawn fertiliser for your grass area.

Lawn Area

Measure or estimate your lawn area

Feed TypeGranular is easier to apply evenly; liquid gives faster results

SeasonSpring/summer = high-nitrogen greening feed; autumn = high-potassium feed to toughen roots for winter. Summer needs more frequent feeds.

Price per Pack (optional)

Unit price for cost estimation

How We Calculate This

Feed quantity = Lawn Area × Application Rate × Number of Applications.

Granular feed rates: Spring 35g/m², Summer 25g/m², Autumn 30g/m². Liquid concentrate: ~10ml/m² — a 1-litre bottle of UK lawn-feed concentrate (e.g. Westland SafeLawn Liquid, Miracle-Gro EverGreen) covers about 100m². The made-up watering-can solution covers far more area per litre; this calculator counts the concentrate you buy, not the diluted volume — always check your product label as dilution rates vary.

Number of applications varies by season: summer may need 2-3 feeds, while spring and autumn typically need one (granular) or two (liquid).

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.