- Learn More About Sunflower Problems
- Pest Management in Sunflower Plants
- Sunflower Problems with Disease
- Sunflower Seed Worms Effect on the Digestive System
- Homemade Pest Control for Sunflowers
- Soap Spray
- Oil Spray
- Garlic Spray
- What Eats Sunflower Plants?
- Beetles and Weevils
Learn More About Sunflower Problems
Sunflowers are popular mainstays in many home gardens and growing them can be especially rewarding. While sunflower problems are few, you may encounter them on occasion. Keeping your garden clean and free of weeds and debris, however, is your best line of defense in preventing these sunflower problems from occurring.
Pest Management in Sunflower Plants
Not many pests bother the sunflower and those that do only wreak havoc in large numbers. The most common sunflower pests include the following:
- Sunflower Beetles – Sunflower beetles typically feed on the leaf foliage and in small numbers or older plants may seldom hurt the plants. However, on younger sunflower plants, the first true leaves can be severely damaged or completely consumed.
- Cutworms – Cutworms can also damage the leaves of young sunflowers, leaving notches or holes. Wilting may also occur. Again, these are usually not a major issue unless there is a heavy infestation.
- Sunflower Borers – Sunflower borers and stem maggots burrow into the stems of sunflower plants to feed. This can quickly kill the vegetation and other parts of sunflower plants, especially in large numbers.
- Sunflower Moths – Sunflower moths are one of the most destructive pests to sunflowers, laying their eggs within the flowers. Once the eggs hatch, the larvae move into the flower heads to feed, ultimately destroying the plants.
- Grasshoppers – Grasshoppers and various caterpillars also enjoy nibbling on sunflower foliage. While rarely a major problem, large numbers can quickly defoliate plants.
Pest management in sunflower plants involves prevention. Keeping the area free of weeds and debris can help. Damage can also be reduced by treating the area before sunflower pests become well established. Later planting, such as in June or July, may also help alleviate any problems. While there are many broad spectrum insecticides available for sunflower use, organic insecticides, which are deemed safer, can be used as well – including Bt products.
Sunflower Problems with Disease
Although sunflowers can be affected by some disease problems, rarely is this an issue, as these plants are typically quite hardy. Various leaf spot diseases may cause surface spots or yellow patches. Rust, verticillium wilt, and powdery mildew can also affect sunflower plants on occasion.
However, the most common threat to these plants is Sclerotinia stem rot, also known as white mold. This fungus can cause sudden wilting of leaves, stem cankers and root or head rot. Crop rotation can reduce the likelihood of this disease as well as proper watering practices.
Sunflower Seed Worms Effect on the Digestive System
Sunflower seed worms are very common. Remember, while sunflower seeds (at least the kind you find in grocery stores) are processed at a processing facility that is likely FDA approved, seeds still come from the earth. Billions of worms inhabit the earth.
If you have ingested a worm along with your sunflower seeds, chances are, it was dead. Even if it were alive, you needn’t worry. Besides causing you to be grossed out, the worm you found in your bag of sunflower seeds cannot harm you. The worm that you swallowed was likely the larvae of the Indian meal moth and it will not effect your digestive system in any way.
The Indian meal moth does not have any known diseases, it doesn’t carry any known parasites, and it does it carry any harmful pathogens. This larvae or worm is made up of mostly protein and niacin. Other similar insects that could end up in your bag of sunflower seeds include the flour beetle and the sawtooth grain beetle. These insects are harmless as well.
About the Indian Meal Moth
The Indian meal moth’s scientific name is Plodia interpunctata Huber, order Lepidoptera. The moths are 3/8 to ½-inch long with two-toned wings folded over its back. The wings are pale gray with reddish-brown ends. The caterpillars are off-white with brown heads and they grow to ½-inches long. The caterpillars may become greenish, pinkish, yellowish or brownish in color.
The female Indian meal moth lays its eggs in suitable larval food. It may take from 27-305 days for the egg to develop into an adult. Seven or eight generations may occur in a year. The caterpillars hatch from eggs and produce silk tunnels to protect themselves while feeding. Larval development varies depending on type of food and temperature. The caterpillars have chewing mouthparts that chew through Indian meal, flour, whole wheat, cornmeal, shelled corn, dried fruit, seeds, crackers, biscuits, nuts, powdered milk, chocolate, candy, red peppers, and all types of pet food.
While medically harmless, finding moths flying around the home can be annoying. This is an indication of a breeding population in the home. The caterpillars can also be found crawling on ceilings and walls in search of a place to spin a cocoon. When found in food, you might also notice the caterpillars’ loose silk mat on the top surface of the food.
Not to be mistaken for the clothes moth (Lepidoptera: Tineidae) which does not have two-tones wings, but rather uniform gray wings, the Indian meal moth is easy to kill. Al it takes is time and patience. If you suspect that you might have an Indian meal moth infestation, check all opened boxed (or plastic bag) food in your pantry for moths, caterpillars or webbing. If you find any of the three, discard the food. This means throw it in a garbage bag and take it outside immediately.
For any remaining unopened food products, put them in the freezer until you are ready to use. Keep in mind that freezing for a few days kills all stages of the moth. It’s unlikely that the moths can penetrate through cardboard boxes, but it is possible for them to chew through very thin plastic. Don’t forget to check all shelving and surrounding areas in your pantry and cupboards.
If you need some help with locating the infestation, pheromone traps may be helpful. The traps can help locate the general area of the infestation down to a room or a closet. They might even help to eliminate small infestations. Pheromone traps will last anywhere from one to three months. Simply place them in several locations for maximum benefits. Continue to replace the traps until you notice that the traps are free from captured months.
If you want to avoid eating anymore of these protein packed creatures, simply check the inside of any boxed food products before chewing them or cooking them up. This is very easy to do. You can pour the contents into a large mixing bowl and sift through it or pour the contents into a strainer and sift. The same goes for pet food, as meal moths tend to lay eggs in bags or boxes of cat and dog food as well.
Note: Using insecticides in the kitchen or pantry is dangerous, so be ruthless in your search for the Indian meal moth and you will be successful at eliminating them without having to resort to using harmful chemicals.
Homemade Pest Control for Sunflowers
ants & ahises image by Marek Kosmal from Fotolia.com
Making a homemade insecticide with a few natural items from your kitchen is a safe and economical alternative to commercial products. Sunflowers are hardier than most plants and are able to withstand attacks from the majority of garden pests. The most common sunflower invaders are aphids and ants, who create a type of mutual farming community on sunflower branches. Sometimes gardeners will plant sunflowers throughout gardens to purposely lure aphids and ants away from other plants and then douse the pests with an insecticide.
Fill a jug or pitcher with one gallon of water. Measure out 2 tbsp. of dishwashing liquid, preferably organic, and 2 tbsp. of baking soda. Mix well with the wooden spoon.
Choose an industrial-type plastic spray bottle. Label the plastic spray bottle with a permanent marker to remind you of its contents. Using the funnel, fill the spray bottle with the soap spray.
sun flower image by MAXFX from Fotolia.com
Spray the soapy mixture directly on pests hiding within sunflower branches. Check the undersides of leaves and spray them top and bottom. Apply to sunflower plant daily until pests disappear.
Fill a liquid measuring cup with 1 cup of vegetable oil. Gradually add 1 cup of dishwashing soap. Mix well with a spoon and set aside.
Fill a spray bottle with 1 tbsp. of the vegetable oil and soap mixture. Using the funnel, fill the spray bottle with water. Save the remaining vegetable oil and soap mixture in a jar or plastic container to make more oil spray as needed.
Remember to label the spray bottle with a permanent marker to prevent mix-ups. Apply directly on pests and sunflower leaves, shaking the bottle to mix as you go. Apply to sunflowers weekly.
spray bottle nozzle image by Kathy Burns from Fotolia.com
Fill a pitcher with 1 quart of water. Measure in 1 cup of vegetable oil. Mix well using the spoon.
Finely chop 1 large clove of garlic. Add the chopped garlic to the water and oil mixture. Mix well.
Add 3 tbsp. of dishwashing liquid to the garlic mixture. Cover the container, and refrigerate the contents overnight.
Strain the garlic pieces out of the liquid mixture the next morning. Using the funnel, fill a labeled plastic spray bottle with the garlic oil spray mixture. Apply directly to pests and sunflower foliage. Use weekly to keep pests away.
I’m having another Wildlife Lover’s Moral Dilemma, but this time it’s of a different sort. Up until now, my love of butterfly caterpillars has known no bounds, and I’ve gone out of my way to plant larval host plants and create a Caterpillar Hotel and so forth. But today caterpillars have rained on my parade, and my beloved caterpillars have come back to bite me, or at least my precious flower favorites.
It’s been raining a lot lately, and so I’ve not been in the garden too much, grudgingly recognizing that the nutsedge and bermuda are taking over again in the meantime. But a glimpse out my bedroom window got me excited — blooms lower down on the tall Cinnamon Sunflowers meant I had a chance to take new photos of my dark red blooms. I rushed outside in a dry pause from the rain… to a horrible sight.
The first thing I saw from a mere glance was a mass congregation of black on the leaves of one of my yellow sunflowers. Caterpillars, and a lot of them.
Then my eyes opened wider. There were more on the plant next to that one. And on down the short row.
Then I was hit with the realization that they’d completely defoliated many of the leaves of the yellow sunflowers, to the point that I’m not sure whether there’s a future in sight for any of the already-struggling annuals.
In fact, I’m quite certain that two of the smaller plants are dead, or at least zombies. I hadn’t even shown a photograph of a bloom from the poor traditional flowers — I’d been waiting for them to get bigger. I felt such sadness.
And then, like a scene in a horror movie, I turned slowly to look at my Cinnamon Sunflowers, dread gripping my heart.
The first thing I saw was caterpillar poop, and a lot of it.
Ok, something’s eating my Cinnamon Sunflowers. Looks like a few caterpillars. At this point, I’m still thinking it’s ok — I knew the flowers were larval hosts. I accepted that.
But as I opened my eyes beyond the poop to the damage and destruction above, around, and beyond, my heart started breaking.
I have what I can’t seem to call anything else — an infestation — of literally hundreds of caterpillars of all sizes. I knew by the spines that there was a good chance they were butterfly caterpillars, but still… in those numbers?
Part of me wanted them to be something that I could consider pest caterpillars, so that my moral dilemma could be simpler to deal with and I could find a soapy bucket of water. But no, as near as I can tell, these are the larvae of the Bordered Patch Butterfly. At some point, I am going to have incredible numbers of chrysalises and several dead, once beautiful sunflowers. Was this gorgeous butterfly from just a few weeks ago one of the culprits?
Despite the destruction, I can’t bring myself to dispose of the caterpillars, or feed them to the birds, nothing. Must… love… caterpillars.
I can’t love the butterflies without supporting their eggs and babies. I guess I’m just going to have to watch them devour my plants and hope that the sunflowers, at least the larger ones, will recover.
I thought about moving the Bordered Patch caterpillars over to the Zexmenia, also a host plant. But that’s when I discovered hundreds of caterpillars were over there, too. My beautiful Zexmenia, already getting eaten up, too. Gah! It’s ok, Meredith, it’s ok… planted as a host plant. All good.
Here’s what I want to know: when exactly did these Bordered Patch butterflies show up laying eggs? And OH MY GOSH JUST HOW MANY EGGS CAN THEY LAY? Holy cow. And where are my beneficial predators now, now that I need some ecoystem balancing? Hello birds, stop feasting on my seeds and get yourself some live protein. Leave a few so there’s still a good population of butterflies, please. Why didn’t anyone tell me that Bordered Patch butterflies and their cousins are the rabbits of the butterfly world?!!!
According to some sources online, Straggler’s Daisy, or Horseherb, is a larval host plant for the Bordered Patch. I’ve got plenty of horseherb, so I did try moving some of the caterpillars over. They wouldn’t eat while I was watching, and then the rain came again, so I’ll have to monitor them for awhile before moving the rest over. Cross your fingers — there’s a glimpse of hope for the sunflowers if I can pull this off. I’m not holding my breath for too long, though, since so many other sites didn’t list the little groundcover as a favorite host plant.
Between the masses of caterpillars eating my CinnSuns and the masses of nutsedge and weeds abounding in my garden, I just want to cry. And yet, I’m so happy we’ve had rain — just an absolutely wonderful thing in central Texas during the summer. And I can still smile at the Gulf Fritillary caterpillars on the passionvine.
I saw one starting its chrysalis stage today — it’s a J right now — and I happily discovered a chrysalis hanging from a Mexican Redbud branch. (I also discovered a passionflower bloom in the redbud tree — that pesky vine has done it again!)
But overall I feel like I’m being tested, and I’m not sure whether I’m passing or failing. Passing as a wildlife lover with a high level of tolerance for munchers; passing as a butterfly grower. Failing as a gardener who wants beautiful, intact plants around; failing my new sunflowers. This isn’t my veggie garden– with my tomatoes, it was a war I had to engage in, those hornworms and stink bugs. Now the line in front of me is blurry. Should I be thinking of the crazy numbers of caterpillars as pests or be happy that I’m supporting more butterflies?
No worries, it’s still the latter. I just need to get used to this new concept of caterpillar quantity and re-evaluate my planting methods. Clearly I need more sunflowers so that my plants aren’t so easily overtaken. That will work, right? Learn to share, butterflies!
Hang in there, sunflowers. I know this is tough love from mama.
A smile from a damselfly to cheer us up… 🙂
Bittersweet. That’s what it is. Bittersweet.
What Eats Sunflower Plants?
The sunflower, with its tall stalks and distinctive yellow and black bloom, is a drought-tolerant plant with a short summer growing season. The beauty of the sunflower is appealing not only to people but insect pests that eat foliage, roots and flower of the plant. Cultural control and applying chemicals can keep your sunflowers from being eaten.
Beetles and Weevils
Beetles and weevils are among the insects that primarily feed on the roots and stems of the sunflower plant. The carrot and longhorned beetles deposit eggs on or near the sunflower plant; the larva hatch during the growing season and sustain themselves by eating the lower parts of the plant. The flea beetle also eats sunflower plants, but feeds on the leaves and seedlings of the plant. Wilting and irregular holes on the sunflower leaves can indicate a beetle infestation. Weevils vary in size and color, deposit eggs in the walk of the plant and feed on the stems and leaf tissues of the sunflowers. Weakening of the plant and root structure can be a sign of weevil presence. Tilling the soil well to eliminate larva that has not yet damaged the sunflowers can be a non-toxic control method. Chlorpyrifos-based pesticides may also be needed, depending on the level of infestation.
Moths eat sunflower plants as well as beetles and weevils. The sunflower moth feeds on the head and seedlings of the plant, while the sunflower bud moth damages the stem and unopened buds of the plant. Moths leave a sticky, webbed reside on the plant as well as holes that indicate its feeding path. Larvae that feed on sunflowers can lead to stems that are misshapen, and the stunted development of the head of the flower. Natural trapping using pheromones can control the sunflower and sunflower bud moth population. Insecticides containing the chemical phytomelanin may also be considered for management.
Sunflowers can provide an ample meal for a number of wiggling, crawling pests, including maggots, caterpillars and army worms. Painted ladies and woollybear caterpillars can render significant defoliation of the sunflower plant as they munch their way through the leaves and flowers of the plants. Green army worms and cutworms are also major offenders of sunflowers and leave ragged holes or “windows” in the leaves. Windows are transparent areas on the leaf that occur when the larvae or young stages of the creatures begin to feed on the sunflower but are not big enough to poke a hole through the entire leaf. The threat of defoliation to at least 1/4 of the plant’s surface or the entire crop usually warrants using a chemical control against crawling pests.
Grasshoppers eat sunflower plants but generally do not cause as much damage as other insect pests. Grasshoppers can be hand picked off of the plants when the population is small. Larger infestations may require chemical controls to prevent the young nymphs from migrating to neighboring fields or gardens. Beta-cyfluthrin and acephate are two non-restricted chemical controls that you can use in non-crop areas to manage grasshoppers on sunflower plants.