Fungicides

[missann]

Hello again. I bought some 5$ phals. (actually they are Dtps) but lots of the roots are rotten, and I would like to know if it is safe to use copper fungicide directly on the roots, or is this something I should use only for the leaves?

I have cut all the dead roots off, and soaked them in Consan 20 (same active ingredient as Physan), but I would like to treat them further before I put them into pots with fresh media.

If it is not safe to use copper soap fungicide in this manner, what can I use?

Please help you guys. I have seen a lot of posts about rotting phals, but when I scanned them, I didn't see any specific fungicide advice. Thanks.

[missann]

Also, I have read to use something called benomyl, but I have looked for this in the past and was unable to find it.

[janet_a]

all i know is you shouldn't use copper products on dens.... all i've seen generally is recommendations of physan. personally i just dunk the plant in hydrogen peroxide for 15 mins or so.

[missann]

Full strength hydrogen peroxide like you use in the bathroom, or the horticultural kind of peroxide? I think there is a difference. Instructions please....

[Sharyn]

missann: I do the same as Janet. Just use the drugstore peroxide. It's always best to use fresh peroxide. Don't use some old stuff you've had in your medicine cabinet for years. I'm not sure of the shelf life once the bottle is opened. It's cheap enough to have a few bottles on hand. Has worked pretty well for me. Good luck.

[janet_a]

yep. if it's safe to use on you, it's ok for the plants. i think it's 3%. (don't use the stuff they use for torpedo fuel...)

hydrogen P, isopropyl (rubbing) alcohol and cinnamon are all good home remedies to have handy for these silly little weeds.

[Sharyn]

I had trouble inserting this link about hydrogen peroxide in my previous post. You might find it interesting.

Better Than Nature - - Articles - The Plant Doctor - Hydrogen Peroxide and Horticulture

[digitalgate]

normally , i use this but you have indicated that the roots has rotted. Give the plant an environment where the root can't rot.
meaning you may have to lay bare (no media) for a while as it is summer now. Let it regrow
roots and put fresh media back before fall. That is how i grow $5 phalaenopsis.

[missann]

Digital-what kind of humidity do you have for this bare culture, and how often do you water? I was thinking of doing that, or mounting it, but I don't have a big enough mount. I had good luck with having them just set in their pots with no media, but I don't want the roots to dry out totally. Put them in big bark pieces in clear pots, so I can see what is going on down there.

[Andrew]

Personally, I wouldn't use copper fungicides on anything mildly green. There are plenty of other newer generation fungicide that work as well if not better. If you're after an 'organic' alternative I've found orchids handle sulphur fairly well. As for benomyl/Benlate, while it was a good fungicide and is one of the few effective and fairly gentle fungicides against grey mould it was taken off the general market several years ago. There may be a few specialists or agricultural suppliers who still have it available.

[Anton]

I agree with Andrew, keep the copper based ones for the floor of the the GH, and try one with with Macozeb in it for the plants.

I find this and another one we have in Australia called Fongarid, good if used in rotation, that way the fungus doesn't become immune to a single product.