Have you noticed those metallic green and purple beetles munching away at your rosemary bush? Those are likely rosemary beetles. While they won’t kill your rosemary, their feeding can damage new growth.
Before you reach for harsh chemicals, give some natural pest control methods a try. You’ll be able to get rid of these pests and protect your plant using simple, organic techniques.
Best of all, you won’t have to worry about toxic residue on an herb you may use in cooking.
The rosemary beetle (Chrysolina Americana) is a common pest that feeds on rosemary, lavender, sage, and other herbs. This little beetle, about 8mm long, munches on leaves and flowers.
Both the adult beetles and the larvae (small slug-like grubs) can do a great deal of damage to plants . You’ll often spot these rosemary bugs in groups on the stems of your plants.
Also, the beetles are most active during the late summer months. So if you see these colorful critters congregating on susceptible plants during this time, you’ll want to take action before they get out of control.
How to Get Rid of Rosemary Beetles Naturally
These are home remedies and natural control methods you can employ. With diligent monitoring and these organic controls, you can win the battle against these shiny bugs and enjoy your herb garden.
1. Pick Them Off
The most natural way to control rosemary beetles is to simply pick them off the plant manually. Check your plants regularly. Since the beetles tend to gather in groups, you may be able to remove many at once.
Pick them off and drop them into a container of soapy water to kill them. Also, remove any larvae and rosemary beetle eggs you notice on the leaves.
Repeat this process every few days.
Inviting birds to your garden is another way to control rosemary pest populations. Several bird species prey on beetles and their larvae.
To attract birds, provide a bird bath or fountain for drinking and bathing. Also, set up bird feeders with seeds, nuts, or suet cakes.
Place them near aromatic plants like thyme and lavender, where the birds can easily spot the beetles.
Once the birds discover the beetles, they will return frequently to feed on them. The birds will also feed on rosemary beetle larvae and pupae, helping to reduce future generations.
Frogs love to snack on the larvae and adult beetles as well.
If you have a pond or water feature in your garden, frogs may already inhabit the area. However, if you don’t have an existing frog population, you can create a frog-friendly habitat to attract them.
Once the frogs discover your garden oasis, they’ll start patrolling for lavender beetles and other garden pests.
A single frog can eat thousands of insects in its lifetime . Therefore, attracting a few frogs to your yard will make a big dent in insect pest populations in an eco-friendly way.
4. Garlic Spray
One of the most effective natural repellents for sage beetles and other insect pests is garlic spray. Garlic contains compounds that act as natural insecticides and repellents.
The strong garlic odor will deter rosemary beetles. As an added benefit, the garlic water will also act as a natural fungicide.
However, for severe infestations, you may need to combine this homemade rosemary beetle spray with other methods like handpicking beetles or using row covers.
5. Neem Oil
Neem oil is also potent enough to help get rid of rosemary leaf beetles.
To use, mix 2 tablespoons of pure, cold-pressed neem oil with 2 teaspoons of mild detergent, like dish soap, and a gallon of water.
Spray the solution directly on the rosemary beetles and their larvae. It will kill the beetles before they become adults.
You can also spray this home remedy on your plants to deter these and other pests from feeding on them.
An organic insecticide containing pyrethrin can be an effective way to control bugs on rosemary plants.
The pyrethrin will paralyze the beetles and larvae, causing them to stop feeding. They’ll eventually die.
However, be very careful when using pyrethrin, as it can also harm beneficial insects. Spray the product in the evening, when pollinators are less active.
7. Insecticidal Soap
Insecticidal soap is a natural pesticide made from potassium salts of fatty acids. It works by penetrating the insect’s exoskeleton and damaging cell membranes, which causes dehydration and death.
To make your own insecticidal soap spray, combine 4 tablespoons of liquid soap (castile soap works well) and 1 gallon of water. Mix thoroughly and pour into a spray bottle.
Spray this DIY soapy water spray on your plants to kill rosemary beetle larvae, aphids, and other pests. However, if you do not wish to make anything, you can purchase this as a ready-made product and apply it to your plants.
8. IV Organic 3-in-1 Plant Guard
A popular natural pesticide to protect your trees and shrubs is IV Organic 3-in-1 Plant Guard. It contains natural repellent oils like rosemary, peppermint, clove, and castor.
For the most effective results, use this product up to three times per year. It is also effective against rats, termites, mice, caterpillars, and rabbits.
So these are a few simple and natural remedies to help fight beetles on lavender, or bronze-colored beetles, as some call them. Give these eco-friendly methods a try, and you’ll be enjoying beetle-free herbs in no time.
And remember, the key is to start early before their numbers build up and get out of control. With some diligent monitoring and these natural pest control techniques, you can have great success.