How to Make Garlic Spray for Grasshoppers | Natural Pest Control

A homemade garlic spray repels grasshoppers by coating leaves and stems with a strong scent and taste they avoid, though it works as a deterrent rather than a guaranteed killer.

For the full breakdown, see our best Garlic Spray For Grasshoppers guide.

If grasshoppers are chewing through your garden, garlic spray offers a simple, non-toxic first line of defense. The basic recipe uses just garlic and water, with a small amount of mild soap to help the mixture stick to foliage. It won’t wipe out every grasshopper, but applied consistently, it drives them to look elsewhere for dinner. Here’s how to make it right and where most recipes go wrong.

Why Garlic Spray Works on Grasshoppers

The smell and sulfur compounds in garlic irritate grasshoppers’ sensory systems, making treated plants unappealing. Garlic spray is a repellent, not an insecticide—it encourages grasshoppers to move on rather than killing them on contact.

The key is coating every surface where grasshoppers feed and hide, including the undersides of leaves and along stems. Miss those spots, and you’ve left them a buffet.

The Basic Garlic Spray Recipe That Works

Multiple tested recipes follow the same pattern: crush garlic, steep it in water overnight, strain thoroughly, and add a splash of mild soap. Let it sit for at least 12 hours, then strain through cheesecloth or a fine-mesh sieve until no solids remain. Pour into a spray bottle and apply in the evening, holding the nozzle about 6 to 12 inches from the foliage and coating both sides of every leaf.

This concentration seems to be the sweet spot across most tested recipes—strong enough to repel, mild enough to avoid burning leaves.

Don’t assume stronger is better; over-concentrated mixtures increase the risk of phytotoxicity (leaf burn) without improving repellency.

When and How to Apply Garlic Spray

Application timing matters almost as much as the recipe. Spray in early morning, late evening, or on cloudy days when the sun won’t bake the mixture onto leaves and cause damage. The cooler temperature also keeps the garlic compounds from breaking down too quickly.

Spray the undersides of leaves and the stems first—that’s where grasshoppers hang out during the heat of the day. Then coat the tops of leaves. Strain the mixture until it runs clear through cheesecloth or a muslin bag; any solid bits will clog your sprayer nozzle within seconds.

Reapply after rain or overhead watering, since garlic spray washes off easily. Without rain, reapply every 5 to 7 days during active grasshopper pressure. If you’re still seeing heavy damage after two weeks, you may need a stronger option—

Common Mistakes and Safety Notes

The most frequent failure is skipping the strain step. Blended garlic pulp will clog any sprayer, from a hand mister to a pump sprayer, and the uneven application leaves gaps in coverage. Strain twice if needed, through progressively finer sieves, until the liquid is completely clear.

Always test garlic spray on a small, inconspicuous section of each plant type before full application. Some plants—especially tender seedlings, herbs, and leafy greens—can react poorly even to properly diluted mixtures. Wait 24 hours and check for yellowing or wilting before spraying the rest.

Use mild, natural soap as a sticker/spreader—castile soap is the most commonly recommended choice. Harsh dish detergents or degreasers can strip the waxy protective layer from leaves, causing more damage than the grasshoppers would have. If you add optional ingredients like cayenne, onion, or mint, note that these increase residue and may stress plants further; they aren’t necessary for the basic repellent effect.

Leftover spray keeps in the refrigerator for about a week in a sealed container. Shake well before each use and discard if it develops an off smell or visible mold.