pot size and medium

[kvet]

Hi there!

Would someone kindly help recommend a pot size, and let me know if I can use orchiata SUPER size (3/4"-1", it's large) on its own? And can I wait 45-60 days to do this?

Key points:
- each orchid remains in its original, 4" plastic pot, now three years in May
- bottom of each plastic pot was cut off
- one big ceramic pot was filled with medium-large orchid bark from the nursery (Uni-grow or something like that)
- the three plastic-potted orchids were half-buried into the bark
- I understand as a general rule with orchids, it's best to repot not when they bloom, but rather when there's growth
- I've read it's okay to repot phals when blooming
- all three orchids had a mild mealy bug problem December-February. With persistence, I have not seen a mealy bug since February 15!
- dendrobium is 30 days into blooming, and has a new growth (I cut a notch into the pot to let it grow last week)
- phal also 30 days into blooming, second spike appeared a couple weeks ago, no plant growth
- phal's roots circle the entire pot
- zygo appears to have new growth and new roots

Photos of the den and zygo growth attached. You can see picture of the pot with all three orchids in post #5 here: multiple orchids in one pot, one has mealy bugs

I'm a little confused as far as re/up potting at this point for the dendrobium, it is blooming *and* growing!

Given the new growth, and three years in the same medium, and outgrowing their pots, I think it is time to repot. A member here was kind enough and willing to help with this in person, however, that's a no go until the shut-ins are lifted. Since I'm a little afraid of messing this up given the sentimental nature of the plants (don't care about the pots), will it be too late to repot them if I wait another 45-60 days?
I gave each pot a gentle tug to see maybe I could just lift them out, but it appears roots have grown down into the medium as well. Given this, I have no idea what sort of pot dimensions I should look at.

With the roots growing downwards an unknown about, how do I know what height pot to purchase? And diameter 5" or 6" or larger?

Also, I have ~18qts orchiata large bark remaining. It was an impulse buy. I had large perlite to match, but ended up using it in another project. Can I use the bark exclusively? Should I mix with equal size perlite and/or lava rock?

Thank you for your time, hope you are all well

[Keysguy]

Holy moly that's a lot of questions in one post!

Help us out a little bit more if you can..... are these window sill grown? Are you going to try and community pot them again or do you want to separate?

Also, the media you use is very much dependent on your growing conditions and cultural regimen so please help us understand those things as best you can.

I'll start by saying I would not let the critters determine my path forward here for re-potting as long as you are aware of their presence and have a plan to address them.

[Roberta]

Den can wait until it stops blooming... those nobile-type Dens don't stay in bloom all that long, and it'll be continuing its growing and rooting well after that. That large Orchiata is on the big side... but I have found that the big (Super) has a lot of smaller pieces mixed in (sizing is not as consistent as the smaller sizes)... you could sift with a 6" net pot or something similar to find the smaller pieces, probably nearly half the bulk. Zygo looks like it's ready... that one really should go into somewhat smaller bark (since it likes to stay a bit damp) Again, you could use the smaller pieces of what you have, perhaps mix in some sphagnum for moisture retention. Pot a little larger but don't go overboard... if it was in 4 inches, 5 would be about right.

As far as mixing in some inorganic (like perlite or lava rock), that's fine... maybe 1/3. It's purpose is to keep the mix open. I use it more with smaller size bark - the big stuff stays pretty open anyway.

[Ray]

Adding to Keysguy's comments...

Certainly, you CAN us straight Orchiata Super, but you should be aware that it's going to require you to do a LOT of watering.

You can help that a bit with the proper pretreatment.

DO NOT soak Orchiata, or you will extract some of the dolomitic lime they add when aging the stuff. Instead, put enough bark for your immediate need in a plastic container, and slowly trickle boiling or very hot water over the stuff - enough to thoroughly wet it without a lot of runoff. Wait 15-30 minutes and repeat. When it's cool, it's ready to use.

The hot water will cause the bark structure to open up so it'll hold more water going forward.

[kvet]

Hmmm, sorry, I didn't think three questions would be too many? I did provide a long background, sorry to omit a few items.

Yes, I would like to break them into individual pots at this point.

They are kept inside, ~2 ft from a due-east window. I keep the patio door a few feet away from them open 24/7 (unless it's raining). I usually keep the drapes open but sometimes in the summer I will pull them across as it can get pretty intense. RH in my house averages mid 60% throughout the year. Plants have been in this location, unmoved, three years. Picture of them in-situ (or is it in vivo?) attached.

[Roberta]

Definitely they need to be in separate pots.

[kvet]

Ray and Roberta, ah, looks like you responded as I was replying to Keysguy : I also have some coconut coir, it's not the ground up stuff, pretty loose. Attached what it looks like I could mix that in with the bark so I wouldn't have to water as much? The packaging says it has been rinsed already, I need to double check and make sure it is not full of salts (I have a tds meter from a project long ago, I'll just soak in distilled water over night and check).

I'm not trying to be cheap, just using up what I have. I can get smaller orchiata and/or some of the fancy moss, too, I am just not quite sure what at this point after reading so much out there. I know a lot like going to inorganic medium, but I don't think I'm ready for that with these - my success with inorganic has been poor for some reason.

[Roberta]

You can use that coconut coir instead of sphagnum as an additive. Do soak it well and check... salt content is very dependent on its source.. if ever exposed to salt water, pretty impossible to get it all out.

[kvet]

Okay, I'll get some 5" pots then, I can get the smaller sized orchiata as well. Will the pots be deep enough? I have no clue how far down the roots go. Is it okay to jiggle the plant out, measure, then go get the mix?

---------- Post added at 10:41 AM ---------- Previous post was at 10:33 AM ----------

Out of curiosity, what's the purpose of orchiata super? Used as a topper, or, do people use them with specific orchids? I don't really see the large sizes used at all when browsing images here.

[DirtyCoconuts]

edited as my comment was redundant

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