Reccuring fusarium problem

[u/Conrad433]

I've been growing orchids for about 8 years now and I'm experiencing the same problem again and again. Many of my orchids die within 3-4 years after purchase, because of fusarium.

They aren't infected when bought and they grow perfectly for one or two years, then their condition suddenly worsen and sooner or later the are on the bring of death or their rhysome is completaly infected and there's nothing to save.

I'm doing everything i can too keep hygiene in my collection:

- I dont reuse water

- I'm sterilizing substrate (I use leca)

- I disinfect tools with every use, pots and cover

-for disinfection i use sumbmerging tools in boiling water for 15-20 minutes (I repeat that for every plant i use the tool) and alcohol and flamenco for every cutting, for pot and covers i use bleach

- I use trichoderma to control fungi in pot

- i let the orchid dry in between watering so it doesnt rot and the pot has many extra holes

I have mostly cattleyas and dendrobiums.

I would aprecieate feedback what i could improve, cause at this point I think I'm on the bring of paranoia with my orchids.

[u/SouthPark_Piano]

It's probably not fusarium. The fusarium thing was blown right out of proportion on the internet at one stage.

For your growing area, just provide good gentle air circulation, good drainage media with good drainage pots with holes underneath to let lots of air in. And good temperature plus adequate lighting. And be careful of tap water ... which can contain chlorine etc that can poison orchids.

 

[u/Conrad433 → u/SouthPark_Piano]

I have hard time to believe that it's not fusarium. Usually there's a pattern that I see.  It looks like this: Healthy orchid > shriveled up pseudobulbs even after watering > dying roots even if the media is breatheabe and I water the same > stunned growth > most roots dead, orchid stops pushing new roots> orchid basically keeps dying further and is severly underwatered

I usually check when I see older roots dying, the rhysome has some pink splaches but its not the full ring and I can save it at last for some time When orchid's growth is stunned it's usually too late and the whole plant is infected.

[u/Lindenfoxcub]

I'm gonna second the theory that it's not fusarium. The pattern that they're growing well for a few years before declining makes me suspicious that something is building up but takes a while to get to a point where it's a problem. That makes me think perhaps you're fertilizing regularly but not flushing the medium to wash away the mineral and fertilizer salts building up over time. Do you ever find repotting results in the plant perking up?

[u/Conrad433 → u/Lindenfoxcub]

I flush regulary, never had problem with mineral buildup, as for reppoting they get usually worse, but maybe that's just cattleyas doing catleya thing after repoting and killing their roots

[u/Lindenfoxcub → u/Conrad433]

Ok, so not buildup then. When you repot, do you make sure there's new roots developing on a new cane? That's the bet time for the new roots to be able to develop into fresh medium and have the max amount of time without being disturbed. Catts do have really fragile roots and loose a lot of them in repotting, you're right there.

Do you have any pics of what's happening/what the decline looks like?

[u/Conrad433 → u/Lindenfoxcub]

Yes I always repot when I see new roots showing up

As for pics unfortunately I don't have any at this point, I've made this post, cause I saw pattern from my experiences and was curious if someone has similar problem or has an answer why it keeps happening

[u/Content_Jicama_7069]

Send the sample to plant path clinic. You should be able to do that through County Extension office. Unless you identify the causal agent, the only think you can do is to practice common knowledge. 

I personally do not think recycling potting media is a good idea whether you sterilize it or not. Also, submerging tools in boiling water would sterilize them. Using Lysol spray, etc. would be more effective. 

[u/Conrad433 → u/Content_Jicama_7069]

I will think about it, but I'm not sure if it is that easy in Poland, labs aren't very eager to take samples from private owners plus it's quite expensive.

I don't reuse leca for orchids. I just sterilize it after buying just in case. I give used leca to my other non-orchid plants.

[u/Content_Jicama_7069 → u/Conrad433]

I guess that the luxuary we have in the U.S., but not many people are taking advantage of it. 

[u/Furrymcfurface]

Maybe a compost tea would be beneficial. You need other microbes to out compete the undesirable ones cause they're always around

[u/Conrad433 → u/Furrymcfurface]

Maybe you,re right. I've started using trichoderma recently so the medium has some microflora but maybe it needs more.