How do you bare root a Catasetum for its dormancy?

[isurus79]

Originally Posted by Ray

Concerning the “rest” for such plants, it’s more about “no nitrogen” than “no water”.

I’d take Steven’s advice about the “hard rest” and just let it go dry, as I have no first-hand experience, but many S/H growers simply water normally and stop all feeding.

I would add to keep the plant warm (above 55 degrees) if the roots stay wet during dormancy. The potential for rot increases in cooler temps.

[mopwr]

Originally Posted by isurus79

The potential for rot increases in cooler temps.

This has been my observation as well, for more than just catasetinae too. Do you know the science behind that?

I think I've heard it has something to do with slowed metabolism coupled with being less efficient at / unable to perform gas exchange when roots are wet... Essentially, the idea is, they can't use water fast enough and it's not evaporating (or being transpired) as quickly, the roots stay saturated with nowhere for the water to go, roots being saturated means they can't perform gas exchange so they die (suffocated) and rot.

Of course, I'm no biologist and have only gathered bits and pieces from what's on the web (which admittedly is often a better source of misinformation that tangible measureable facts).

[isurus79]

Originally Posted by mopwr

This has been my observation as well, for more than just catasetinae too. Do you know the science behind that?

I think I've heard it has something to do with slowed metabolism coupled with being less efficient at / unable to perform gas exchange when roots are wet... Essentially, the idea is, they can't use water fast enough and it's not evaporating (or being transpired) as quickly, the roots stay saturated with nowhere for the water to go, roots being saturated means they can't perform gas exchange so they die (suffocated) and rot.

Of course, I'm no biologist and have only gathered bits and pieces from what's on the web (which admittedly is often a better source of misinformation that tangible measureable facts).

I honestly don't know the mechanism. I've always assumed the plant is quite literally shut down and is unable to deploy it's defenses against what is otherwise an easily beatable infection during active growth.

[SG in CR]

Originally Posted by isurus79

I would add to keep the plant warm (above 55 degrees) if the roots stay wet during dormancy. The potential for rot increases in cooler temps.

That makes sense to me too. I've always wondered why a lot of people say Catasetums need a hard dormancy when I've had a C. maculatum in a tree that I water every evening once the dry season kicks in for like 10 years. But my temps never really go down below 65 and during the dry season never below 70 (85-90 daytime and 75-80 nighttime would be typical). I've been doing it for years and it's one of the biggest plants I know of, though it does seem to produce more bulbs that stay a bit smaller than if they get a really dry dormancy. Here in CR, the dry period is the hottest and sunniest time of year. Which is a big contrast to northern growers who have it go through the opposite. My guess is that might be part of the problem. Catasetums probably want heat and light when dormant.

[isurus79]

Originally Posted by SG in CR

That makes sense to me too. I've always wondered why a lot of people say Catasetums need a hard dormancy when I've had a C. maculatum in a tree that I water every evening once the dry season kicks in for like 10 years. But my temps never really go down below 65 and during the dry season never below 70 (85-90 daytime and 75-80 nighttime would be typical). I've been doing it for years and it's one of the biggest plants I know of, though it does seem to produce more bulbs that stay a bit smaller than if they get a really dry dormancy. Here in CR, the dry period is the hottest and sunniest time of year. Which is a big contrast to northern growers who have it go through the opposite. My guess is that might be part of the problem. Catasetums probably want heat and light when dormant.

Yep, some are more seasonal than others, as described in Arthur Holst's book. And watering with temperatures above 55 degrees F is ok, as told to me by Gene Monnier some time ago. Makes me miss Hawaii! lol