Pot depth for S/H?

[Imperial_Exotics]

Currently I have been moving plants into 32oz fruit fly cups.

These seem to be ideal for a couple of reasons:

1. they are deep. I can drill holes, 1" up from the bottom that leaves a nice reservoir to retain water for wicking action with the hydroton.

2. Plenty of room for root growth without the roots being immersed or saturated in standing water.


I also purchased 16oz. plastic cups at our local Smart and Final, (they are 'soft sided' clear cups like the fruit fly cups)

However I think these may pose a problem for use in a S/H setup. The biggest being that they are short. I cannot drill holes that will allow for a reservoir of water, as they are so short, any orchids planted in them, even young ones, will be in contact with water.

One possibility I see is to drill the holes in the bottom of the cups, then placing the cups in 10" x 20" nursery trays with a small amount of water in them.

Considering the massive root growth on my Doritis, I'm hesitant that this is a good idea even for really young plants.

for the record, these cups are 4.5' wide, and 3" deep.

Are these usable for S/H or not?


thanks

[trdyl]

I hope you mean 4.5 inches and not 4.5 feet. Those will work. For plants that a 4 inch pot is large enough I like using 20oz Solo Brand Clear Cups which I drill. For small seedlings I like Dixie Cup sized plastic cups. One thing I have noticed is that when plants are grown in S/H thier roots are shorter as long as they are in the container. The ones that grow over the sides of the pot get pretty long. I have a couple of Phals that have some aerial roots a couple of feet long. While the roots in the pot are only about 6-8 inches long.

[Imperial_Exotics]

hmmm.....

so drill in the bottom and set in nursery tray then?

Like I said, my biggest issue was concern over submerging roots.

[trdyl]

Having the roots submerged is not an issue when they grow into it. One of the other benefits of the side holes is they allow ventilation of the medium. I would not use bottom holes for S/H. I would only use bottom holes for non S/H applications.

[Ray]

1) Don't submerge the roots in the reservoir when you pot them up. As Ted said, they will grow into it, and that's fine.

2) Don't forget that you're balancing the wicking rate (fixed) with the evaporation rate (variable), so a really tall aspect ratio might lead - under some conditions - to the water never reaching the upper part of the pot.

[Imperial_Exotics]

Originally Posted by Ray

1) Don't submerge the roots in the reservoir when you pot them up. As Ted said, they will grow into it, and that's fine.

that is why I was skeptical about being able to use the 16oz cups. Drilling up 1" from the bottom leaves me less than 2" of space for planting, and that is presuming I pack the cup to the rim with hydroton.

That said, I don't see the 16oz cups being usable. Unless it's freshly planted young plants fresh out of the flask.

Originally Posted by Ray

2) Don't forget that you're balancing the wicking rate (fixed) with the evaporation rate (variable), so a really tall aspect ratio might lead - under some conditions - to the water never reaching the upper part of the pot.

Not a problem there. I check the plants frequently, and they are in a very large greenhouse with lots of humidity. In fact, the first batch I 'planted' this way had very long roots, almost reaching the bottom of the cup. These are already starting to show signs of blooming and it's only been a week.