S/h pot size

[Algyros]

I'm taking the plunge into S/H with three cattleyas. The pots in which they are growing are 5" across the top. I repotted one in a 5" Deli container, but, to my untrained eye, it seems a little cramped.

Is there are rule of thumb for pot size when switching orchids, in this instance, catts, from conventional media to S/H? One of the things I was thinking about is that since there is no organic medium to rot, does it really matter how big an s/h pot is, aside from practical or aesthetic grounds?

[vcuchick]

yes! Pot size does matter! I found this out the hard way. I thought when I moved a phal into S/h that I could just keep it in the same diameter pot and go from there, found out that the pot was too deep and the plant really suffered during the transition.

I have found good success in keeping the pots a little on the smaller side. One reason I found is that when you move over into S/H, what usually happens(and not all growers may have this) is that the old roots will die off and new roots will form. The roots will grow to addapt to the new medium/environment so you may see the plants get a little weird at first while they aclimate. I have found the small/shallower pot allows the plant to get used to the idea of S/H faster since the roots have less 'space' to cover to get to the water source. Then once I see it have a nice healthy root system and it's rebloomed in S/H at least once, then I know the plant is good to move into a bigger pot. Basically, if you can take the plant out of the pot and it clings to all the LECA clay balls, and the pot is overflowing and about to burst then it's time to repot into a bigger pot.

I have attached a few shots of my S/H plants for you to see as reference in terms of size of plant vs. size of pot. I have sucessfully had most of them in S/H for about a year and they've really done well.

You'll have to give us updates since I have a new Cat that I may try out in S/H if your project goes well. Good luck!!!

[LouisW]

In my opinion, you should keep your conditions in mind when deciding what is best for your plants in particular. For example, contrary to Vcuchicks experience I have had luck with very tall narrow pots more so than wider pots. My hypothesis on this is that here I have very low humidity and generally high temperatures making it very hard to keep things evenly moist, even S/H. My pot increases the amount of water in the reservoir while decreasing the exposure to the dry air. The deeper pots stay more moist for me while im sure Vcuchicks pots dont have a problem staying moist up in Canada.

You can expect to lose some roots but if you repot at the correct time they should quickly be replaced by roots adapted to S/H. I would pot up one size as you normally would when transferring to S/H for the first time. Then when the plant is acclimatized to S/H you can pot it up more than you normally would. Because the LECA is inert, stays evenly moist, and guarantees good air passage, there shouldnt be trouble with rot or other problems associated with overpotting.

I would give your plant a little space rather than sticking it in a plant container, making sure that you do not submerge existing roots in the reservoir. Good luck!

[Algyros]

Thanks for the replies. One thing that confuses me is Vcuchicks's statement concerning the roots needing to get to the reservoir. I was under the impression that the reservoir was there to supply a well of water that then could be wicked up into the rest of the LECA and that the roots, although occasionally finding their way into the reservoir, got water primarily from the wet-through-capillary action LECA.