Treating leaf rollers on cannas can be a frustrating task, but there are several effective methods you can try. One option is using Bacillus thuringiensis kurstaki, a natural bacteria that is commonly found in horticultural pest sprays. This bacteria specifically targets and kills caterpillars, including those responsible for leaf rolling in cannas.
To begin, you will need a horticultural pest spray that contains Bacillus thuringiensis kurstaki as the active ingredient. These sprays are readily available at most garden centers and online. Once you have the spray, follow these steps to effectively treat leaf rollers on your cannas:
1. Identify the affected plants: Take a close look at your cannas and identify the plants that have leaf rollers. Leaf rollers are caterpillars that roll the leaves of plants to create a protective shelter. They can cause damage to the leaves and hinder the growth of your cannas.
2. Inspect the rolled leaves: Carefully unroll the affected leaves to expose the caterpillars inside. Leaf rollers are usually small and green, blending in with the foliage. It’s important to identify the caterpillars to ensure you are dealing with leaf rollers and not a different pest.
3. Prepare the spray: Read the instructions on the horticultural pest spray bottle and mix the solution accordingly. Some sprays may require dilution with water, while others may be ready to use. Follow the manufacturer’s recommendations for the best results.
4. Target the caterpillars: Once the spray is ready, carefully spritz it directly inside the rolled leaves where the caterpillars are hiding. The Bacillus thuringiensis kurstaki bacteria will work its way into the caterpillars’ digestive system, causing them to stop feeding and eventually die. Be sure to thoroughly coat the affected areas, ensuring the spray reaches the caterpillars.
5. Repeat the treatment if necessary: Leaf rollers can be persistent, so it may be necessary to repeat the treatment after a week or two to ensure you have eliminated all the caterpillars. Follow the spray’s instructions for the appropriate frequency of application.
In addition to using Bacillus thuringiensis kurstaki, there are other steps you can take to prevent leaf rollers on your cannas in the future:
– Clean up debris: Leaf rollers often overwinter in fallen leaves and debris, so regularly clean up any dead foliage or plant material around your cannas. This will help reduce the potential for reinfestation.
– Monitor regularly: Regularly inspect your cannas for any signs of leaf rollers or other pests. Early detection can help you take prompt action before the infestation becomes severe.
– Encourage natural predators: Consider attracting beneficial insects, such as ladybugs or lacewings, to your garden. These insects feed on caterpillars and can help control leaf rollers naturally. Planting nectar-rich flowers and avoiding the use of pesticides harmful to beneficial insects can help attract and retain these natural predators.
By following these steps and using Bacillus thuringiensis kurstaki, you can effectively treat leaf rollers on your cannas and create a healthier, chemical-free garden. Remember to always read and follow the instructions on the pest spray for best results.
