Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Trouble shoot problems you are having with your cactus.
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PolishGuy
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Location: Poland, dolnośląskie (lower silesia)

Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Post by PolishGuy »

So to make it a bit simpler to understand why I want to spray water starved plants here is a story behind what I want to do and why:

I wanna repot my cacti before I wake them up from winter hibernation, I dont wanna water them before since by reppoting I will damage any new roots.

One of my cacti during winter got rust and I cured it with trifloxystrobin, but I wanna desinfect the rest of my collection with contact copper fungicide, in case they have any spores left on them.

(I wanna use copper contact fungicide since its not systemic and also I will be using micorrhyzal culture in soil and I want to use something milder since these are healthy plants)

Since they are a bit dehydrated (some of them have those soft wrinkles on their bottom) and waiting for moisture to absorb, wont it burn/damage them if I spray them with it?
I dont want them to sense moisture and then open stomata and suck in all this copper water...

Again to make it simpler to understand, I want to spray healthy but a bit dehydrated cacti with copper contact fungicide before replanting them to new pots, and during replanting (after 1-2 days after spraying) wash it off (since I need to wash the winter attick dust from them and loosen up the terrible supermarket peat medium).

And yeah I know Im doing it a bit late but I have to do it now anyways

EDIT: unless its not necessary to spray them with anything if during few month of winter they havent caught anything (but also not even a single drop of water landed on them), I would kinda even preffer not to spray them but if I see those orage-red spots on freshy repoted plants Im gonna be very dissapointed with myself and my day will be ruined...
Poland, dolnośląskie (lower silesia)
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Steve Johnson
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Re: Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Post by Steve Johnson »

If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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PolishGuy
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Re: Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Post by PolishGuy »

I added location sorry about that, just thought that my username was accidentally enough 😅
Anyways I just need to know if its relatively safe to spray water hungry cacti like that, they are kept inside
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greenknight
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Re: Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Post by greenknight »

It shouldn't hurt the cacti - but be careful with that stuff, it's pretty toxic to animals (and you!).

I wasn't familiar with this particular form of copper fungicide, so I did some reading on it. Its advantage is that it's not very soluble in water, so it stays on the surface of the plants longer than copper sulfate. WP stands for wettable powder when it comes to sprays, meaning it forms a suspension when mixed with water, after the water evaporates it leaves particles of the pesticide behind. The plants won't absorb it - and it wouldn't hurt them if they did, it's not toxic to plants. Follow the general rule of not exposing plants to the sun when they're wet with spray, to be on the safe side.

Plenty of Polish guys in this country, too - though I did assume you meant you were in Poland. :D
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Steve Johnson
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Re: Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Post by Steve Johnson »

PolishGuy wrote: Sat May 28, 2022 12:51 am I added location sorry about that, just thought that my username was accidentally enough 😅
No worries -- I thought that you might live in Poland, but I didn't want to make any assumptions.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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PolishGuy
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Location: Poland, dolnośląskie (lower silesia)

Re: Is copper oxychloride (50wp) safe to use on "dehydrated" cactus

Post by PolishGuy »

greenknight wrote: Sat May 28, 2022 1:18 am I wasn't familiar with this particular form of copper fungicide, so I did some reading on it. Its advantage is that it's not very soluble in water, so it stays on the surface of the plants longer than copper sulfate. WP stands for wettable powder when it comes to sprays, meaning it forms a suspension when mixed with water, after the water evaporates it leaves particles of the pesticide behind. The plants won't absorb it - and it wouldn't hurt them if they did, it's not toxic to plants. Follow the general rule of not exposing plants to the sun when they're wet with spray, to be on the safe side.
Thanks, I was also suprised when I read the label, since everyone internationally always seems to use copper sulfate while in Poland copper oxychloride (miedzian 50wp) is like almost "main staple" of copper fungicides

The reason I was asking is that I've read on some website that improper aplication can result in burnt leaves/fruits but it was written in a bit unclear way and sounded like they were describing improper aplication in time but might as well have had dose in mind and so I wanted to make sure.

Ironically I have used more systemic/plant penetrating pesticides than non systemic contact ones so far and with those I was less scared for the plant since it is supposed to be absorbed, so you can understand my hesitation...

And when it comes to safety I pretty much always wear gloves and some n95 mask and generally take shower after spraying/messing with stuff like that so no worries
Poland, dolnośląskie (lower silesia)
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