When planted a few weeks ago we were in the low 80s. Hi Michelle, we use h202 preventatively (in spring before milkweed emerges) and to overwinter plants indoors. H2O2 kills gnat larvae on contact. Thin out the herd– if your milkweed plants are crowded, your milkweed patch can become a breeding ground for fungi. I figure assassin bugs kill lots of caterpillars, like cutworms and loopers, in addition to the occasional monarch or other desirable insect they get. I removed the whole plant to be safe and when I checked the underside of all its leaves I found 2 small cats. Is it safe to use the solution on the plants with eggs? Why are my plants’ leaves turning purple? If an egg is on a problem leaf, you can cut off a small piece of the leaf (with the egg) and place it on a healthy cutting or leaf. A: There are many diseases and parasites that kill monarchs, including viral, protozoan, fungal, and bacterial infections. 4. Hi Brenda, you could always try spraying leaves with a hydrogen peroxide solution and/or removing affected leaves as is listed in the post…, Will the peroxide help with rust spots do the leaves and will it hurt the caterpillars . Over the years, I’ve been less concerned about what’s ailing our milkweed, and more concerned about treating it early. If you don’t have milkweed to spare, you can transplant what you remove: How To Successfully Transplant Milkweed with Taproots. Help! Hi Terry, I use this more preventatively at the beginning of the season and overwintering plants indoors. This article mentions using a hydrogen peroxide mix to kill fungus. Replenish their milk?– for fungi similar to blackspot, try this simple rose remedy after removing the affected leaves: note: If you’re spraying sickly milkweed and notice webbing on the plant, you’re probably dealing with microscopic (almost) spider mites and can check out our milkweed pests page for specific treatment options. I noticed one of my plants started getting the yellow curled/twisted leaves that you mentioned is caused by leafhoppers. Stop Milkweed Pests from Ruining Milkweed for Monarchs. The cats must be protected from them by putting the branches of milkweed in water and bringing them into a protective shelter with mesh sides and a zipper. I will definitely remove these. Hydrogen peroxide also adds more oxygen to the soil to prevent root rot. Thanks! I have them in some pretty sunny places, like full sun and heat most of the day. Monarch caterpillar on common milkweed by Joanna Gilkeson, USFWS. The black spots on my curassavica look exactly like your picture so I’m going out right now to remove the unhealthy ones. I don’t think h202 would hurt them, but I’ve never sprayed it directly on them. It’s been all day now and they’re slow to munch. Use a spray bottle to thoroughly soak the infected plants. Could I have maybe just beat them up a bit too much when I was washing them? Any ideas/suggestions on dealing with this problem. It has never developed into a serious issue, so I don’t believe it’s a fungus/disease. I also need to know if it’s safe to spray with H2O2 solution when eggs and cats are present? I've wiped out the little bastards with BT, but now I'm wondering if a bud wash would be a good idea to clean off any residual BT and leftover caterpillar poop. Thank Tony, for the leafhopper damaged post. 2. It does wonders for the aphids. Of course, they accept no responsibility and told me they know nothing about caterpillars etc. Hi Erin, Asclepias curassavica does not ‘contain’ OE spores…they are left on the plants by sick butterflies taking nectar and/or depositing eggs. Thanks. As of this morning I have officially lost over 40 caterpillars again. I’m in Houston and have been raising asclepias for 25 years. They then told me because I’m using tropical plants and not native that that was the problem. Is this from too much shade or what? Here are some questions to ask yourself if you see either of those symptoms. Thank you, Hi Gloria, I use it preventatively and haven’t had to use it during the season. 2. I figure they are either going to die for sure from the leaf spot (the1 tablespoon 3% peroxide per 8 oz didn’t do anything after the fact), so I might as well treat them aggressively and see what happens. Told me he trusted his vendor and told me he had a few calls with problems with the milkweed. Will hydrogen peroxide kill bugs in soil? Lots of foliage since I trimmed it back. Within the last 2 days I have had several cats die. Native milkweed typically looks pretty bad by the end of the season, so your milkweed may be … Hi Gail, I use the mixing chart for sick/fungusy plants: Sounds like Kathy had a combination of problems. I’m just wondering about future eggs/cats. I need help with my giant milkweed. The milkweed in my backyard raised bed is afflicted by this. I had about 20 healthy butterflies emerge this spring, but the next 10-12 were all diseased. For the first time, my milkweed is covered with rust fungus. Another advantage of the Peroxide breaking down is that it releases free Oxygen into the area. Is there anything else I can do? Hi Joanne, I’ve seen this before too and just removed the affected leaves. Hi Gloria, hydrogen peroxide is actually food for plants, adding more oxygen to the roots. I try and let the caterpillars do it, but in areas where there is rust the stem just seems to die. If an infected butterfly lays eggs, they will be infected and can spread the OE to other healthy cats who crawl over the same plants. I have never heard of these leaves potentially hurting caterpillars, but I’ve never found any caterpillars on those leaves either. These cuttings aren’t a perfect looking as some of the others but I can’t identify what I’m seeing. The herbicide kills all plants in its path, except for the GE crop. Some are more red in color than green. I have since removed my other cats onto another plant. Maybe also writhing in the cage? Which ratio would that be? The brown chrysalises can be a bacterial infection. More info here: I planted tropical milkweed in a sunny area in my moist garden about four weeks ago. Can They get root rot? My swamp milkweed leaves turned purple towards end of summer, then yellow, then red, and now they are falling off. To spray on sick or fungusy plants: TO THIS AMOUNT OF WATER ADD THIS AMOUNT OF 3% HYDROGEN PEROXIDE 1 cup --1 tablespoon 1 pint-- 2 tablespoons 1 quart-- 1/4 cup 1 gallon-- 1 cup 5 gallons-- 5 cups 10 gallons-- 10 cups 20 gallons-- 20 cups As you may notice, the amount of peroxide in the chart for sick and fungusy plants is twice as much as … I don’t spray monarch eggs/caterpillars directly with hydrogen peroxide and not sure if/how it would affect them. I soak the soil with the solution before plants start coming up. Milkweeds can take full sun with some wilt if temp goes up to 110 , temp around 80-mid 90’s should be ok …they don’t need much water after the first year. Hello! It appears like a fall changing leaf, but the leaves otherwise are healthy. I use the measurements for sick/fungusy plants…2 cups in a 2 gallon watering can of the 3%. I would try them. You can kill lots of gypsy moth caterpillars simply by wrapping your tree trunks with a band of burlap bags. As a background, there must be at least 25 cats on the bush which is average size in a container about a year old. Is it dangerous for the caterpillars to eat these leaves? Hi Claire, we typically use the h2o2 preventatively on small plants and soil before the plants come up. I don’t generally treat plants outdoors after the season has begun. When you purchase new plants, it’s best to place them in a shadier area and gradually exposing them to more sun. My success rate is really good. (Skip to the bottom to see what you can do if you find your caterpillars in this situation.) All of it is infected. I bought a few Milkweed plants so I could attract and photograph Monarch butterflies. Thank you so much for this! Any suggestions? I can’t find anything that says if this is normal Fall behavior or not (chicago, zone 5b). I have never seen plants have an adverse reaction to it and I often use more than the charts. Hi Kathy, it sounds like you are having a major issue with tachinid flies. Yes its normally to use Hydrogen Peroxide when making Bubble hash .. We have had a lot of rain. Does that affect the caterpillars negatively if later, eggs are laid on the plants and caterpillars eat the leaves? Hi – I just noticed that my otherwise healthy looking Asclepias tuberosa – butterfly weed – has yellow-ish leaves with dark green veins. We always turn over the soil a few times with a large shovel before planting. One potential bacteria that causes this to happen is: Hi there. They are Less than 1 Year old. I'm at the end of my healing and now stocked up on TTO, ACV, Hydrogen Peroxide for ever! Thank you. The causes of the caterpillars deaths are all different. I have also noticed that the leaves on some plants (even in other locations) are very small. I successfully raised over 50 butterflies at the beginning of the season and now the last 3 cages have been dying as the cats get nice size , they stop eating and just sit there for days and gradually die. This is happening on both our ground-planted swamp milkweed and also on our potted tropical milkweed plants. Is there a way to send you an electronic picture. There are links in the post for how much to use…we use the chart for sick/fungusy plants. Do not compost diseased leaves/stems and risk spreading fungus spores into the soil. What could be causing this problem? Hi Wheelz, this sounds like a potential virus (NPV) or bacterial disease. Hi Kathryn, check out this info for how we use hydrogen peroxide. I watered the soil with hydrogen peroxide earlier this spring (before plants start coming up). I’ve never heard of fungus spreading like this. good luck! All my tropical milkweed has the black spots and then turns yellow. I have gotten better, and I'm covered in scars. Oddly- my neighbors yard has become overgrown with this same type milkweed which were healthy until this past week the leaves have a silvery blackish spotting along them. Anyhow, all plants come back just fine the next season…. Rather than fight the flies and hornets, I pluck off all the eggs and instars and raise them inside. Little yellow spots have developed on the leaves. Leaves can also look mottled if infested with spider mites: Tony, do you have to use food grade hydrogen peroxide? Yeah, I'm kinda scared to see what comes out of my buds. And do you know how much to spray on the ground. Thoroughly inspect your milkweed, rescue any eggs or caterpillars, and move them onto an uninfected plant, or to a protected location, like a netted butterfly pavilion. Remove sick leaves–  Whenever you come across sickly milkweed leaves, remove and discard. Every bit of my milkweed has the rust colored fungus and my catties are eating them, so I hope the fungus doesn’t hurt them either. check out this post to learn more about monarch predators and what you can do to save more monarchs: Hi Tony, is it safe to spray milkweed with a baking soda mixture or would it be harmful to cats. This develops on the leaves then the leaf yellows and drops off. Did you soak the dirt or just spray on top of it?