It’s an all-too-familiar scenario. Daughter wears brand-new white summer dress to family picnic and barbecue. Daughter has a blast playing hide-and-seek and relay races with cousins. Daughter comes home with two large, irremovable grass stains on beautiful new white dress. Maybe the white dress was a bad idea.

Grass stains are probably the most daunting type of stain I have ever tackled (and I’ve tackled many — including poop, blood and, of course, vomit). Grass stains just seem to walk onto our clothes and sit there, not getting up for anything or anyone. No amount of yelling and cursing while you rub it clean seems to help, either. (“Out, damned spot. Out, I say!”)

So why are grass stains so hard to remove? They consist of chlorophyll, the green pigment of the plant’s juices responsible for absorbing sunlight. They also contain chemical compounds such as xanthophylls and carotenoids, which also are pigmented. Because these are all naturally occurring compounds, they will often bind to the fibers of a natural fabric — like cotton, wool or (gulp) silk.

In other words, the stain will set itself in the fibers of the fabric instead of resting on top of it, making it difficult to remove. The exceptions to this rule are synthetic fabrics like polyester or nylon. In these fabrics, the stain will usually just set itself on top and can be washed off easily.

So what’s the secret to getting out these stubborn stains?

First, it’s important to treat the stain right away. As soon as you see a grass stain on your clothes, the clock starts ticking on its eventual permanence. Stains that are given time will set in the fabric even more, making them that much more difficult to remove. So when you see a grass stain, get to work on it right away.

Try soaking the garment in a mixture of dish soap and hydrogen peroxide for about 10 minutes. Then scrub the stain with a toothbrush. Most of the stain should come off, but if not, repeat the process until the stain is completely eliminated, then rinse with hot water and wash in the washing machine as usual. Be sure the stain is totally out before you stick the item of clothing in the dryer, because heat will set stains.

If you happen to remember high school chemistry, you also know that enzymes can help break things down. Another alternative for grass stain removal is to go to your local health food store and pick up some digestive enzyme capsules. If you open these up, you will find a fine powder. Mix the powder with warm water to form a paste, then rub the paste onto the stain and let it sit for a good 10 to 20 minutes before rinsing. Then wash as usual.

There are lots more concoctions you can make at home that may help — some say to use alcohol on the stain, some say bleach, and some say the tried-and-true baking soda and vinegar combination. I suggest trying the above way first, because I think it’ll give you the best results. And the next time you encounter a grass stain, you’ll know exactly what to do. Then that white dress won’t be such a bad idea after all.

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