How do I get grass stains out of clothes?

Grass stains are chlorophyll and plant proteins pressed into the fibre by knee or elbow. They behave like a dye, which is why plain detergent and water usually leaves a green-brown ghost, and why the second wash never does any better than the first.

What you'll need

• Surgical spirit or a biological detergent
• An old toothbrush
• A clean white cloth
• Oxygen bleach powder, for whites (optional)

Step by step

1. Deal with it before it is washed.A grass stain that has been through a machine cycle is roughly twice as hard to shift, and one that has been through a dryer usually stays.
2. Brush off the dry debris first.Dried mud and grass fragments sitting on top will just spread when you wet them. A stiff brush over the dry fabric takes off half the problem.
3. Apply surgical spirit to the stain while the fabric is dry.Dab it on with a cloth, working from the outside of the mark inwards. Alcohol dissolves chlorophyll, which water does not. Test a hidden seam first on anything coloured.
4. Or use a paste of biological detergent instead.Liquid biological detergent worked into the dry fabric with an old toothbrush, left fifteen minutes. The enzymes handle the plant protein even where the alcohol handles the green.
5. Work it in gently along the weave, not across it.Small circles with a soft brush. Aggressive scrubbing on knees and elbows breaks the surface fibres and leaves a shiny patch.
6. Rinse in cool water and check.If green is still visible, repeat before washing. Getting it to a faint shadow before the machine is what decides the outcome.
7. Wash at the warmest temperature the label allows.Unlike protein stains, grass benefits from warmth once the dye has been loosened. Forty degrees with a biological detergent suits most cotton sportswear and school trousers.
8. Air dry and inspect before any heat.Green that survived the wash will be set permanently by a dryer. Dry it on a line, look at it in daylight, and repeat the treatment if anything remains.

Tips

• White vinegar and water at one to two is a gentler alternative to surgical spirit on delicate coloureds, though it needs longer.
• For white cotton, a long soak in oxygen bleach after the alcohol treatment removes the last shadow that nothing else touches.
• Never use bar soap on a grass stain. Soap reacts with the plant tannins and fixes the colour into the fibre.

Common mistakes

• Washing first and treating afterwards — The wash cycle sets chlorophyll into the fibre. Every treatment after that is working against a dye that has already bonded, and results drop sharply.
• Scrubbing hard at knees and elbows — These are the areas where the fabric is already thinnest from wear. Hard brushing raises the fibres and leaves a permanently shiny or fuzzy patch around the cleaned area.

If it doesn't work

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