The juicy, large leaves of basil (Ocimum basilicum) are tempting to humans and insects alike. If grasshoppers currently threaten and attack your basil plants, don't despair. Use an integrated approach to deal with the notorious chompers. When one step doesn't completely slow down grasshopper damage, adding other barriers, traps and repellents is likely to do the trick.
Pick grasshoppers by hand and drop them in jars of soapy water. This method is effective at dealing with small infestations on your basil.
Set a floating row cover over basil plants to keep off grasshoppers. Floating row covers are made of lightweight fabric that drapes directly over plants and is weighed down by rocks or stakes.
Set individual basil plants among other sun-loving herbs or flowers that are of similar height. Grasshoppers prefer beds of the same kind of plant -- scattering the basil plants throughout the garden helps outsmart the pests.
Plant repellent crops around the perimeter of your herb garden. Pot marigolds (Calendula officinalis) and cilantro (Coriandrum sativum) are both annual plants that grasshoppers may be reluctant to cross by.
Apply a garlic oil spray to the basil to repel grasshoppers. To make a homemade spray, infuse 3 ounces garlic of cloves with 1 ounce mineral oil, then strain the cloves after one day. Combine the infused mineral oil with 16 ounces of water and 1 tablespoon mild liquid soap, and keep it in a sealed jar. To use, fill a spray bottle with water and add 2 tablespoons of the garlic solution, and spray the tops of bottles of basil leaves, as well the stems.
Establish "trap crops" either instead of barrier crops or as an additional layer of protection placed outside the barrier crops and the basil. Trap crops are plants that you don't mind grasshoppers eating instead of basil. Keeping grass tall near the herb garden is ideal because it attracts grasshoppers but doesn't get as raggedy-looking after grasshoppers feed on the blades as broader-leaved plants may.
Bury wide-mouthed jars in the soil near basil plants to make homemade grasshopper traps. Fill the jars halfway with 1 part molasses and 10 parts water. Empty the jars of drowned grasshoppers as needed, and refill with the molasses mixture.
Things You Will Need
- Liquid soap
- Wide-mouth jars
- Floating row cover
- Row cover weights (stones, lumber, stakes)
- Marigold and cilantro seedlings
- Mineral oil
- Spray bottle
- Many of the steps for controlling basil in garden beds can be applied to container-grown basil. Set pots of basil among other plants to "camouflage" it from grasshoppers. Among the container-grown plants you might want to grow near basil are grasshopper-repelling calendula and cilantro. Methods such as hand-picking and using garlic spray are also applicable to potted basil.
- According to the University of California's Integrated Pest Management Program, chemical products for controlling grasshoppers can be ineffective for home gardeners. Chemical baits may only kill some grasshopper species at certain points in their life stages. Insecticides can do more harm than good. They aren't very effective at controlling grasshoppers but are toxic to bees and other wildlife.
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