What weight fleece should I use?

17g/m² (ultra-light) is for insect protection and gives little frost cover (about freezing point). 30g/m² is the usual general-purpose grade, protecting to roughly -3°C (often quoted -2 to -4°C). 50g/m² heavy-duty protects to around -5°C and lower. These figures depend heavily on wind and exposure and are not guaranteed — adding a second layer of fleece raises protection further. Set the Layers field to 2 or 3 for cold spots.

How much extra fleece do I need for overlap?

Allow about 30cm of overlap on each side to tuck in and weigh down with stones, bricks, or pegs so wind cannot lift the cover. The default overlap is 30cm per side, but you can change it under Advanced Options if your bed is more exposed.

What is a standard fleece roll size?

Common UK sizes are 1.5m or 2m wide in 10m and 50m lengths, with heavy-duty bulk rolls up to 2m x 100m. The calculator defaults to a 1.5m-wide, 10m roll, but you can enter your actual roll width and length under Advanced Options.

Can fleece be reused?

Yes, good quality fleece can be reused for 2-3 seasons. Fold and store dry when not in use. Replace when it becomes torn or thinned.

When should I use garden fleece?

Cover tender plants when frost is forecast, typically October-April in the UK. Also use in spring to protect blossom on fruit trees and to warm soil before sowing.

GardenCalcs

Fleece Coverage Calculator — How Much Fleece Do I Need

Calculate horticultural fleece needed to protect plants from frost.

Bed Length

Longest side of the bed — strips are laid along this direction

Bed Width

Shorter side — sets the length of each fleece strip plus overlap

Layers

Use 2-3 layers in hard frost; each layer adds a few degrees of protection

How We Calculate This

The calculator lays fleece strips along the length of the bed. It works out how many strips of fleece are needed to span the bed length, then adds an overlap on each side of the width so the cover can be tucked in and anchored.

Formula: Strips = Bed length ÷ Fleece roll width, rounded up. Length per strip = Bed width + (2 × overlap each side). Total fleece = Strips × Length per strip × Layers. Rolls = Total fleece ÷ Roll length, rounded up.

By default it uses 1.5m-wide rolls of 10m with a 30cm overlap each side, but the roll width, roll length and overlap are all adjustable under Advanced Options to match the fleece you have bought.

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.