Budworm problem? Learn how to get rid of them and protect your plants!
In this complete guide, you’ll learn:
- How to check for budworm damage
- Ways to naturally get rid of budworms
- How to repel them for good
- Methods to protect your plants from damage
- And more
By the time you make it through this guide, you’ll have everything you need to know to control, manage, and eliminate these pests!
Bookmark this page so you can easily come back.
Sound good? Let’s go budworm-free!
Last updated 12/30/19.
What’s a budworm?
A budworm is a common caterpillar that’s commonly found on conifer trees and plants. They chew flower buds and eat them from the inside out.
Budworms larvae are tiny and are often found during the summer months. They’ll mature and grow larger over time before dropping into the soil to pupate.
They’re very destructive pests and will eat vegetative buds, causing them to not open or destroyed from being eaten.
Budworms populate quickly and rapidly breed if not exterminated and managed quickly.
This can destroy many of your plants, such as geraniums, nicotiana, rosebuds, and petunias.
Budworms are also known as conifer, spruce, tobacco, geranium, petunia, nicotiana, and calibrachoa budworms. They’re also often called ester or western spruce budworms.
Their scientific name is Heliothis virescens and part of the Choristoneura genus.
Budworm color varies depending on the species. They can change color depending on their location and what they eat.
By default, they come in multiple colors like yellow, black, tan, and any mix of them.
Where do budworms live?
Budworms are found all over the US and other places like Canada and even New England.
In the United States, they’re often found in New York, Maine, Colorado, Minnesota, North Carolina, Utah, and many other states.
Budworm vs caterpillar
Budworms are the larvae form of moths. A budworm is technically a caterpillar, however rather than turning into a butterfly, budworms turn into moths.
Budworms are also a lot more destructive to your plants and can rapidly multiply. You need to act quickly if you want to control them, as these guys aren’t playing around. A single adult budworm can lay up to 1000 eggs!
What do budworms look like?
Budworms are often found crawling on the stems or flower buds on plants. They’re the caterpillars of moths and will chew through anything that they find tasty.
You’ll find them only during the summer as this is when the larvae start to feed before pupating into a moth. They’re mainly active during the night.
Caterpillars can be black, green, tan, and yellow. They start out at less than 1/16” and grow up to 2” in just a few months.
After they’re done eating, they’ll drop to the soil to pupate into moths and restart the process.
Each adult caterpillar budworm can lay up to 1000 eggs in a few days all over your plant leaves and stems. This is why they’re so difficult to stop and why there are so many of them.
Budworms can also change color to match their food source, which acts as protection making them harder to see.
What do budworms eat?
They eat various flowering buds, trees, and bushes depending on the diet. For example, tobacco budworms eat alfalfa, cotton, tobacco, clover, and soybean.
They also eat a lot of veggies and edibles like cantaloupes, lettuce, pea, pepper, pigeon pea, tomato, squash, and more.
Tobacco budworms are especially fond of flowering plants or nutritious ones like ageratum, bird of paradise, petunia, zinnia, snapdragon, strawflower, verbena, chrysanthemum, geranium, and others.
The larvae also feed on weeding plants like sunflower, velvetleaf, prickly sida, passionflower, beardtongue, black medic, cranesbill, groundcherry, honeysuckle, morning glory, toadflax, and deer grass.
Budworm life cycle
All budworms come from an egg, which is laid on plant leaves, stems, and buds.
After they hatch, they’ll seek out nearby flowers or leaves and start eating them. As they eat, they’ll go through several instars. And after a month, these caterpillars will grow many times its own size before dropping off into the soil and burrowing about 4-6” below to pupate.
They emerge as adult months. Depending on the species, they may eat different foods or have different coloration.
The two most common ones are tobacco budworms and spruce budworms.
You can tell the difference between tobacco vs. spruce budworms by the coloration and spots.
- Tobacco budworms have cream-colored moths that are about ½” wide with a wingspan of slightly over 1”. The budworm larvae feed on annual buds and leaves.
- Spruce budworms are darker, tan moths with 2 semicircular spots on both wings and the larvae feed on conifer trees.
What do budworms turn into?
Budworms turn into moths.
They’re the larvae caterpillar life form of moths. Unlike butterfly larvae, these are very destructive caterpillars that’ll eat up your plants- especially rosebuds.
Where do budworms hide?
They spend most of the time hiding inside flower buds eating them from the inside out.
Since they’re tiny after they’re born, they can wedge their way into a flower by chewing through it. This makes it very difficult to spot them until you notice the flower not flowering or has ragged petals.
They’re protected by the bud and the only way to notice without actually damaging the bud is to look for tiny holes. You can then remove the bud and take a chance. This will prevent the budworm from developing and breaks the life cycle.
Signs of budworms
You can check for budworm eggs on the underside of leaves and buds. They’re gray to white in color.
You may also find tan budworms, which are newly born budworms.
Also check for black deposits on buds, which look like tiny sesame seeds. All of these are signs of budworms. Other telltale signs are chewed up flowers, failed blooms, and jagged petals.
Here are some DIY remedies you can do at home to get rid of budworms naturally.
There are many different ways to go about doing so, but these should get you started.
Removing budworms manually by hand is an effective measure.
Even though this requires you do some manual labor, you’ll find that you’ll quickly reduce their populations on your rose, petunias, tomatoes, geraniums, and other plants just by picking them off.
Make it a habit to check your yard daily before or after work and remove them. Put on a pair of garden gloves and skim your plants quickly. When you come across a budworm, remove it by hand and dispose of it.
You can get a bucket of water with dish soap (14 drops per 2 cups) to quickly kill them. Pick them off one at a time and drop them into the soapy water to eliminate them.
The best time of day to catch them is dusk, as this is when budworms are most active. The dish soap will drown them and kill them. Repeat this process daily until you notice a dent in their numbers.
Bacillus thuringiensis (Bt)
Bt is a natural bacterium that lives in the soil and is commonly used for pest control.
You can buy Bt in various amounts and they usually arrive in a package or vial. The bacteria are planted into the soil and will consume and kill caterpillars, budworms, moths, and other larvae. While this approach is nice because it’s natural and hands-off, you may do some collateral damage to other beneficial bugs.
Not only does Bt kill budworms, but it’ll harm other species like butterflies by killing their larvae. This is only something you can decide if you want to proceed. You should only resort to using Bacillus thuringiensis if you have a ton of budworms that you can’t control.
Remove the eggs
By removing the budworm eggs you come across during your daily checks, this will also dramatically kill off the population.
The eggs are hard to see, but if you carefully check under the leaves, flowers, buds, or stem, you’ll them. They’re clear to white to gray in coloration, and you can scrape them off or remove the leaf you found the eggs on entirely.
Dunk it into a container of soapy water to kill the eggs and then dispose of them. Rather than just killing one budworm, you just killed an entire brood. Now that’s efficient!
Don’t use fertilizer
When you over-fertilize your plants, the excess nutrients may end up attracting more pests to the area, such as roly polys.
You should limit your usage of plant food during the time you’re trying to get rid of the budworms. This will just make your job more difficult if you constantly attract more bugs.
Prune your plants
Prune off damaged parts of the plant and dispose of them.
You don’t want to leave any dead or dried leaves as they can attract other pests. Carefully clip any damaged leaves or flower buds, and also remove any that are infected with budworm eggs.
The nutrients and water that get logged make your plants prone to disease and weaker. With budworms already munching on them, you don’t want to further damage your plant’s health. This is especially true for germanium and jasmine.
Chili spray can be an effective home remedy to control and repel these bugs.
You can make it by using any type of odorous or potent spice. Think of jalapenos, dried chilies, or sriracha.
Take the chili and cut it up into small pieces, or just get it in powder form. Mix it with some water and put the pot on the stovetop until boiling. Then cool the chili mixture and add 2 drops of liquid dish soap.
Pour all of it into a spray bottle and spray it directly on budworms or onto the leaves and stems.
The smell of the chili sticks to the plant because of the dish soap. Thus, this is both a repellent and budworm killer that’s all-natural.
You can even make it organic if you use organic chilies and ditch the dish soap. Or just dish soap made from natural chemicals to keep it natural.
For those with budworms on veggies or fruits, you may want to avoid the dish soap.
Will neem oil kill budworms?
Yes, neem oil will kill budworms and help keep them off your plants.
Neem oil can be purchased at most hardware stores and you can make your own budworm pesticide at home.
Just add 2 tablespoons to a gallon of water. Then pour some into a spray bottle and spray it directly onto the plant. The neem oil is powerful and can be harmful to specific plants, so you’ll want to test it on a small part of the plant first.
Use it on a single leaf and see how the plant reacts after 2 days.
Neem oil can also be toxic to beneficial bugs, so it can definitely disturb your garden’s ecosystem. It’s also toxic to bees, so only use it after dusk when bees are no longer present.
Don’t use neem oil during the day when the sun is out because it can overheat and burn plants. You should also rinse your plants after you spray the oil. Don’t use more than once per week for pest control.
How do you make insecticidal soap?
You can make your own soap by using a few drops of dish soap and a cup of water.
The soap drowns the budworms after you spray it on them. Any dish detergent will do the trick.
Note that some plants are sensitive, so test on a single leaf before applying to the whole entire plant.
Lure natural predators
You can also use the power of nature and attract other bugs that eat budworms to your yard.
This way, you can have other pests take care of the worms for you, even when you sleep. The first step is to find out what predators are native to your area and already present.
You’ll have a hard time trying to attract something that doesn’t already exist, right?
Here’s a list of common predators that eat budworms:
- Robber flies
- Carabid beetles
- And some mammals
Remember that budworms start out as larvae (actual worms) that eventually pupate into a moth.
Depending on the part of the budworm’s life cycle, different predators will eat different phases.
Some bugs will eat the budworm eggs while others will eat the small budworm larvae. Others will eat the actual month after it breaks free from the cocoon.
Do some research to see if any of those are already in your yard? Have you seen any before? What can you do to attract more of them?
Budworms during flowering
If you notice budworms during the flowering of your buds, this is a clear sign that you have a problem.
The petal or flower can appear to be jagged or uneven. And if you see budworms on the actual flower, they’ve likely already eaten up most of the content which results in a poor or failed bloom.
You need to take action and stop them by checking the rest of the blooms.
Prune off the buds that have yet to bloom and check for tiny holes, black deposits, or eggs. This is one way to stop the life cycle of budworms and prevent another generation.
Remember that each adult can lay up to 1000 eggs, so you want to prune off all these eggs or scrape them off manually. It’s impossible to get every single egg, so you should complement your efforts using some kind of homemade soap spray or repellent.
Does Sevin kill budworms?
You should always avoid and use natural or organic pest control.
They’re also dangerous to bees, so you should avoid using synthetic pesticides when possible.
And these residues are dangerous for both humans, pets, and the environment.
Protecting your plants form budworms
Most budworms can be managed with persistence and patience. Use the tips above and the following ones for methods to control budworms on specific plants.
Budworms on roses, petunias, jasmine, and geraniums
If you have budworms on these plants, use a mixture of natural repellents such as essential oils, spices, and manual removal.
These plants are more sensitive, so they don’t take well to harsh pesticides or extreme measures. Also, consider pruning any buds that are damaged or failed blooms.
Tomatoes are also a common vegetable that are often abundant with budworms.
You’ll want to be careful with the treatment method you use because you’ll want to keep the tomatoes edible. If you’re growing organic tomatoes, don’t use any inorganic techniques.
Stick to using something basic like manual removal, spice repellent, or blast them off with a hose.
Potted plants are easier to manage with budworms because you can relocate them as needed.
You can try spraying them down with a hose, then adding spice repellent, dish soap, and/or neem oil. Prune any damaged greens.
Snapdragons attract budworms and can be handled just like any other plant.
Pay special attention to the colored foliage to check for damage. Prune off any visible damage to get rid of the caterpillars, and also check and remove eggs.
Don’t take chances with this plant. If you suspect that there may be eggs, prune it off.
Here are some other resources you may find helpful:
- Heliothis virescens – Wikipedia
- Tobacco budworm – Hortsense – Washington State University
- Native Budworm – Pest insects and other invertebrates
Did you get rid of the budworms?
That’s all I have for you.
By now, you should have everything you need to know to control, repel, and manage the budworms in your yard and protect your plants.
If you have any other questions, leave a comment below.
Or if you found this guide to be helpful, let me know! Tell a friend!
Thanks for reading.
Currently an active researcher in the pest control industry for the past 8 years- with a focus on using natural and organic methods to eliminate pest problems.
I share handy DIY pest techniques I come across here to help out others (and possibly save them from a mental breakdown).
Fight nature with nature.