Winter 2024 | Fungus outbreak in my cactus collection & seedlings!

Do you remember seeing the beginnings of rust fungus in last week's video after our week of winter? It was especially obvious on the grafted Ortegocactus macdougallii. It got even worse after I recorded that video... And the cactus are dry in this video, it looks even worse when they're wet and you can see behind the trichomes...
I'll show you the cactus that seem to be affected the most. We'll also go over one treatment option I tried, and then talk about another treatment I am going to try. Because more rain is on the way!
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Bonide Captain Jack's Copper Fungicide:
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Southern Ag Garden Friendly Bio Fungicide Organic:
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[@CactusCaffeine]

I also use that Copper fungicide. I hope you eliminate those rust. It happens to some of my cacti outdoors, mostly to my columnars.I think the cold plays a factor. But as soon as summer starts, it stops and the cactus heals but with scars.

[@ceciliaarchibold8187]

A lady from Spain told me I have to use a systematic treatment… hoping for the best !!

[@claudekim7876]

Id use systemic and contact for rust. Once established rust is extremely hard to kill. You can get grass slow release fungicide at HD called diseaseEX (aboxystrobin) and also something like bioadvanced 3 in 1. (It also kills bugs, same stuff in pet flea drug, and tebuconazole, one of the best rust killing fungicides) If the organic options dont work that is. But better make a decision before it gets worse!

[@cookiescacti]

Yeah, I need something stronger to stop the spread and then perhaps the more natural stuff as maintenance. Next winter season I need to spray before the rains come in (if I can remember). Any comments on the effectiveness of copper fungicide?

[@claudekim7876]

@@cookiescacti never tried copper but i hear it can be effective but also i just searched it up. It says it can cause damage if used in cooler wet temps. Also if its too hot it can damage too. The systemics do not damage.

[@cookiescacti]

@@claudekim7876 thank you for looking this up! Have you heard about systemics not being effective when the plants are dormant? I have so much research to do...

[@claudekim7876]

@@cookiescacti contact systemics like tebuconazoles work well esp on rust since rust is only skin deep.

[@mrspeachi4378]

That’s terrible!! Hopefully you can get a handle on things quickly. I have had only 1 gymno that had signs of rust, and I put sulfur on it (I already had the sulfur on hand) and it seems to stop the fungus in its tracks. I’m also excited for the prospect of a CC trivia😂I initially had gotten that asterias from PlantStory using your code, but I was so happy that I went back to the seller and splurged on a superkabuto and and beautiful ariocarpus retusus. I’ve been in cacti heaven!

[@cookiescacti]

PlantStory is so addictive! Omg I'm on it so often... Anytime there's a cactus live I find myself unable to tear myself away! I applied to be able to go live for the giveaway. I'm thinking possibly April when most of the country has warmed up so I can ship the plants. Now it's a matter of keeping the plants alive and healthy until then.... Definitely keeping them away from all this rust fungus!

[@cookiescacti]

And I'm so glad you're having a good experience with it! It's so much fun and I feel like there are some good deals to be had! I've already spent the first batch of credits on plants for the giveaway ☺️

[@Teromi]

hows your ventilation? you may need more of it to keep the environment as dry as possible.

[@cookiescacti]

Well, they're sitting outside with 50% shade cloth as the ceiling and walls of the structure, so they're getting rained on but air should move fairly decently through the shade cloth. Do you think that's enough for ventilation? My thought is that the plants have to be able to take the elements here.

[@Teromi]

@@cookiescacti 100% especially if they get rain on that moisture on the dermis is absolutely a breeding ground for fungus. I have a semi enclosed outside growing area with a close off ceilings and still run fans. it has helped out tremendously with mite problems and fungus. I live in FL so not just rainy but constant humidity. Maybe a shade solution that would not let water in but dry dry dry is key. they should be able to withstand the elements but the wind and natural ventilation they would get is intense. most green houses/ grow houses are drafty with evident circulation.

[@dannyf8-nv668]

Oh no! Hope you get a handle on it, and damage is minimal. Fortunately I haven’t had to deal with this, but I should probably get some supplies in preparation. Thanks for the ps code, I used it towards a purchase from Thorn Oasis. Best of luck 🤞🏼

[@cookiescacti]

I swear the challenges of growing plants never ends! Same with all the learning that comes with it. I think I've attended every one of ThornOasis's lives on PlantStory so far. They have the coolest plants and for some pretty good prices too! I'm so addicted to the app omg...

[@billgolightly7203]

I grow inside year around and sulfur works for me. I use an oscillating fan and dehumidifier 24 hours a day, so not much rust.

[@cookiescacti]

The sulfur is a great suggestion, simple and inexpensive! I just picked up some from the store yesterday and I'm giving it a try.

[@ceciliaarchibold8187]

How do you use it on your cactus ?

[@cookiescacti]

@@ceciliaarchibold8187 the sulfur comes in a really fine powder, so I just took a paintbrush and dusted the powder onto the skin of the plant. I heard folks warn not to let direct sun onto the plants when treating.

[@morningstar8187]

Professional nurseries have access to far more powerful fungicides and insecticides than regular people. There are a lot of chemicals that are highly effective at combatting pests but are also extremely toxic and dangerous to handle. You need special permits to buy and use them.

[@claudekim7876]

U can get almost any of the fungicides used by pros in homedepot in usa.

[@cookiescacti]

Uggghhh I'm trying to stay away from chemicals as much as I can for now (it'll be a last resort). I'm trying bacillus and sulfur powder first, if it can't do the trick then something stronger. We'll see...

[@investidoramador9850]

go heavy on fungicide i have 2 brand fungicides on the rain season in brazil its hell,we have like 20 days in a row with rains and the air humidity is breeding ground for fungus

[@cookiescacti]

Oh my gosh, I can't imagine so much rain! Do you prepare before the raining season and then just treat regularly throughout the raining season? What part of Brazil are you at? I have some colleagues in Belo Horizonte.

[@investidoramador9850]

@@cookiescacti i am more down south in parana,actually this past october was the rainiest in 50 years we had like 500mm in a month ,yes i have an outside plastic covered shelf where i keep most of my plants during the rainy months ,u usually aply fungicide every 15 to 20 days,depending on the air humidity,copper based like that one you got and also defeconazole baased,which seems to be the best one

[@yaddahaysmarmalite4059]

I've been using captan. I mix the captan into the water I water my plants with. I've never been sure of how effective it is. A couple years ago, my plants started having a big break out of rust (again); every single one of my plants were infected. So, I painted neem oil onto them and probably a couple other things that I don't remember. Then refused to water them for a couple years. Some died but the survivors seem to have much less rust now if not seem free of rust. I watered them for the first time about a month ago. 2 weeks ago I repotted them; they needed repotted anyway. Today I will be watering them again and yes captan will be mixed in. I hate using neem and copper fungicide because they both permanently stain my plants. Cedars and pine trees harbor rust fungs btw. That's why you can't plant apple trees near those trees. My plants initially got rust about 15 years ago from a pine tree that was hanging over my apartment balcony. Now I keep my plants indoors under lights all year long. I like the idea of using a bacteria that eats fungus. I'd like to give it a try.

[@cookiescacti]

Oh geez that must have been so rough with that fungus breakout. I don't think there are too many pine trees around here since I'm in Arizona. But clearly there are fungus spores EVERYWHERE. What part of the country/world are you at?

[@paradoxicalocus3761]

How tragic! Best of luck with treatment, and thanks for sharing the info. The flip side of the joy of raising living things is when they go wrong (and boy do they!)

[@garygilliam1890]

I’m sorry that you are Dilling with a rust colored fungus I am dilling with a black fungus in the greenhouse

[@fenrik8178]

To be fair when I buy cacti most of them already had a lot of these spots, since they don’t seem to be spreading compared to another plant on which they’re definitely spreading my guess is some kind of damage spots instead of rust fungus?

[@andersnrregren9087]

The dark spots on my plants are not fungi or rot but just frost/cold damage water makes it worse but it stays on the plant forever but dont spreed and can not be cured only heat can stop it from getting worse, but internet will try to tell me its fungi buts its for sure the cold

[@cookiescacti]

Hi Anders! As long as the plant lives, it's all good! You know your plants better than the internet. I hope you're staying warm!

[@morningstar8187]

I had rust on my Myrtillocactus geometrizans “boobie” cactus literally days after bringing it from a fancy plant store. I never went back to that store. I was gonna just toss it, but I decided to try an extreme treatment first. I washed it well in soapy water until it was just bare roots without any soil. I let it dry completely away from any cacti for a couple of days. The I sprayed it with 70% alcohol. I made sure to rub all the spots. I repeated the alcohol treatment multiple times. I then repotted it into fresh soil and kept it away from any plants for a long time. The spots haven’t come back yet, and the cactus is growing well.

[@cookiescacti]

Nice! Basically washing all the fungus and spores off that you can? Now I'm worried that I can't sell or give any plants to other people because who knows about contamination? I guess this is where new-plant-quarantine comes into play.

[@Hsjsisjdjdh]

I don't know if I'm crazy for saying this but I don't know if the rain passes through the metal protection or not. For me it's constant humidity and water on the cacti's skin, it looks like localized drops of water that pass through the protection and are always falling in the same place on the cacti constantly in the rain. It's just my opinion. Just protect the top.

[@cookiescacti]

There is no protection from the rain at all. It's just 50% shade cloth all around the structure. I'm pretty limited in what I can do to the structures due to fears of violating city code... Which I think I already am. I have to make sure whatever my neighbors can see isn't too visually offensive. So my mentality is that the cactus must be able to take the elements!

[@tracemolzon4525]

Please update if the captain jacks worked

[@Chaotic-Cacti]

The sulfur powder can work well. It repels pests, kills fungus & it can be applied anytime of the day but the rain can wash it off.

[@cookiescacti]

I like how simple it is to handle. Now my grow area has a constant special odor 😂I've read that sulfur should not be applied when the temperature is above 85F, do you happen to know why?

[@Chaotic-Cacti]

@@cookiescactiSorry I didn’t see this till now, I would say it’s just to keep the cactus skin dry, I think whoever said that probably thinks ur making a watery paste with it. I’ve never had a problem with it on my cactus with it dry an the temps above 85F.

[@oleander7755]

Hello, I don't know why you want rain on your cacti in winter. I live in the north of Belgium, moderate winters, some freezing days, so the cacti go into the garage, only one door with glass, quite dark, completely dry, 6 months a year, and they come out healthy. Too much moisture in their resting period, combined with low temperature. Beautiful collection, didn't know those spots are fungi. I have them on astro which I sprayed. Won't do that anymore. Apologies for the wrinting errors.

[@cookiescacti]

I live in the desert so I figure these plants have to be able to take the seasons. There are some preventative measures I can take next time to try to combat the fungus. Another reason I leave them out is that I don't have space indoors to put them, so everyone stays outside. Otherwise, most of the plants love the winter rains, and many of them look the best in the winter. The bigger challenge here is usually the summer...

[@icebiker3]

My plants are inside under lights for the winter. I have a dehumidifier and fan going 24/7 and no problems with fungus. Spider mites and mealy buds are my issue and I use Neem oil if I see a problem.

[@cookiescacti]

That's a nice setup! I will find a nice balance between having an outdoor setup, letting the plants get the winter rains they enjoy so much, but applying preventative measures for the fungus next winter season. Hopefully, I won't be making another video like this a year from now!

[@zeahlessley6108]

If it helps, i was able to stop rust from progressing on my lophs by lightly dusting/brushing them with powdered sulfur

[@cookiescacti]

Thank you for the advice! I like this type of treatment, easy and inexpensive. I picked up some sulfur yesterday a did my first round of dusting. Although I swear I'm tasting sulfur everywhere now LOL.

[@Fabdanc]

I would make sure to treat the soil as well because the spores likely sit in the soil as well. I might also use some Root Shield+ to treat the soil. It's... Esspenseeve... $125 per pound, but you can keep it in the fridge for several months. I have found it super effective at getting rid of harmful soil fungi.

[@cookiescacti]

That's a good point. Would you recommend root treatment during the winter?

[@ЕвгенийЗобов-ь5щ]

You need to build a heated greenhouse to keep plants in winter. Ortegocactus was definitely covered with spots from the cold.

[@cookiescacti]

What about just taking preventative measures for the fungus? I can't put a greenhouse structure in my yard unless it's less than 6 ft tall (such that my neighbors can't see it). I also don't want to completely block off the plants from getting winter rain because they like it. Just the fungus is a problem

[@kes1171]

Keep Astrophytum asterias out of cold rain in Winter.

[@cookiescacti]

Is it just because of their susceptibility to fungus or something else? I left them all outside last winter and they did great.

[@tayk702]

Just some tidbits, I've learned that fungus, viruses, and bacteria spread by water/ rain, wind, animals, pruning, insects, and stress. So it's also important to get after the pest or disease at the proper time of year, like when how fruit trees get sprayed when they're dormant. Which makes treatment more effective. Good luck with ridding your plants of that nasty fungus!

[@cookiescacti]

Absolutely 100%. I think the lesson I'm learning from reading through all the comments is that I need to do some preventative measures next winter season. The plants seem to enjoy the winter rains and so does the fungus lol. So I'm thinking to apply the preventative treatments ahead of the rain next time if possible.

[@tl317]

I love all the previous comments and completely agree with sulfur, but would also think that the soil could use more aeration and you might not have the same problem more perlite I would assume if you unpot the plants and let them dry, it should stop. I’m thinking they might just have wet feet.

[@cookiescacti]

They definitely have wet feet because they're outside and got rained on multiple times this winter. I'll try to treat the fungus but there are way too many plants to unpot and I don't have space with light and protection to dry them out. They'll just have to take it! The majority of the plants are planted in 75% pumice and 25% cactus mix. That should be gritty enough... I hope. I need the organics for the summer because then it's the exact opposite, super hot and extremely dry.

[@tl317]

@@cookiescacti wow that’s amazing. I’m definitely gonna have to watch my back that’s about the mix. I’m running as well. Sounds like a great set up with just a little too much rain so sorry. Such a bummer. 😮‍💨 i’m in Tucson and it has been wet. Best of luck to you. I can tell you you made me make a change which is an oscillating fan in my greenhouse, so thank you for that because I probably had the same thing coming. You might’ve saved my life.

[@terrizimmerman5297]

Jenny, do you sell your cacti?

[@cookiescacti]

Not after the fungus decided to ruin everything! 😭😂😭😂😭

[@morrisparkintheozarks6831]

I've had a problem with this the last few years. Both Cactus and Euphorbias. Started using a systemic fungicide by Bromide. I've had a good bit of success with it except in some opuntia & a couple of my Euphorbia hybrids. I'm trying to save a one of a kind Euphorbia right now. I've cut off one branch and set it aside. So far so good, I'll root it soon. The rest is in collapse. Doesn't seem to have affected any other Euphorbia hybrids on the table except one small horrida X polygona hybrid which died. Affected all my cactus seedlings and has all but wiped them out. Sprayed all , some plants did very well. My Euphorbia collection in the greenhouse did well with this treatment. The rust dried up and turned a tan corky color when healed. Good luck, seems cactus fair the worst with this. But my Euphorbia ceriformis X horrida looks horrible! Good luck with treatment, hopefully it works on them! Fingers crossed for you!!! From Morris Park in the Ozarks, out to Arizona, have a wonderful day!!! Peace, Love, Plants!!!✌️💖🌵🌷🌴🌸🌿🌻🍀🌾💐🌱🌹🌳😃👍

[@nancylee1883]

Jeepers Jenny 😮 I was wondering how your plants were going to fair in the cold temperatures you had. That rust looks like a real challenge. I hope it quits spreading and that you find a quick cure solution to the problem.

[@cookiescacti]

So far the plants are doing pretty well, just that darn fungus! I got some good suggestions from all the folks who left comments here. Now I'm trying some of the easy, simple, inexpensive ideas first. Then we'll see.... How's the winter treating you so far Nancy?

[@nancylee1883]

@cookiescacti For me personally, the winter has been great. We have had a number of +40 degree days. It's raining here today, which is unheard this time of the year. Typically, in January we'll have some -40 degree days. That being said, the weather has not been good for our winter tourism activities or our logging industry. Other than the lack of sunlight, there isn't much difference for my plants. I have a living room full of grow lights--I'm pretty sure astronauts can see my house from space 🤔

[@investidoramador9850]

i saw a green plant on one of your cactus.they should be bone dry in winter not wet

[@cookiescacti]

Which green plant needs to be bone dry? Is it the adenium you're referring to?

[@investidoramador9850]

@@cookiescacti i saw some small weed seedlings on your pots,they should be dry to the bone,

[@cookiescacti]

@@investidoramador9850 Ahh do you mean the wild weeds? They're everywhere after the rains lol! I live in Arizona and the plants love the winter rains! Last year the mature Arios and Astros absolutely loved the winter rains which is why I did it again this year, but it's the seedlings' first time. Now I'm learning that some fungus management will be needed in the future and then we should be all good! ☺️

[@kathylovejoy2569]

I think you need to invest in solid sides that rain cannot get in, for the winters. Then go back to shade cloth in the summer. It would be well worth it, as you have a lot of expensive plants in there. If you put up solid sides, would lights and a heater help as well? Just taking guesses at this problem, but you have had problems with the shade cloth before. I am so Sorry to see your beautiful cactus in bad shape like that. Hope you can find a solution. From Alberta Canada,

[@newmanmansell760]

It's shocking to see that rust fungus. I hope the fungicide does a good job.

[@nmumpton]

I am so sorry for the rust infestation on your plants. Hope the spray works. I have plants in pots but not as many as you and they are out in the open. They have gotten a lot of rain and now I’m afraid the roots will rot. Desert plants are so challenging sometimes.

[@dnawormcastings]

Wow first time seeing this in plants nice information video 🇳🇿

[@janelladalupang2115]

I'm sorry to hear about the rust outbreak. I'm currently battling it this winter. I've lost some already. I went through several stages of grief lol and I'm at the stage of "bin it" if the plant condition gets too bad. It really challenges the love for this hobby when there is an outbreak. Thank you for the video! I feel like not a lot of cacti hobbiest show rust damages on the plant.

[@monsterbanger2017]

The copper spray is like old technology, it can work but it’s definitely not 100% proof, I prefer using new technology fungicides , I would also treat once a month till there is absolutely no trace , for some people they need to go further like changing soil mix to be more accommodating to there condition

[@joshualennox3599]

I think I would risk thrasher attack for the sake of different levels of isolation. A series of large dog cages or chicken coops at the extremities of your property perhaps?

[@cookiescacti]

Interesting idea... I was also thinking I need a quarantine space somehow. Next winter season I'm going to see if I can remember to spray everything before the winter rains. I'm more concerned about me remembering to do so though

[@TavoAnzures]

Fungicida Ridomil gold 💯👌

[@cookiescacti]

Thank you for the recommendation!

[@TerryJent]

Get a fan!

[@cookiescacti]

Any good ones that can take the elements?

[@tim1280]

Hi cookie 😻

[@cookiescacti]

Hi Tim 😻