Over potting in S/H?

[EmoryG]

Aloha All,

Am I right to think that plants would be much more tolerant of being "over potted" using s/h than more traditional (bark/sphagnum based) mixes?

I am wanting to repot a couple of recent purchases, Phrag. manzurii and Phrag. fischeri each with a leaf span of about 4". Of the containers I'm fond of using, the smallest are about the size of a 3" or 4" inch pot. Thoughts or concerns?

Side note: I have read that Phrag. fischeri likes it more alkaline and was thinking about mixing in oyster shells into the mix.

As far as my cultural considerations, I am in Hawaii with average humidity around 80%, pretty good ventilation and I water my phrags with rain water PH around 6.4. Typically I soak the plant in a solution of seaweed extract+inoculation before potting them in a mix of viastone, diatomite, small charcoal (roughly 6:2:1).

Thanks so much for the support.

[Subrosa]

The width of the pot isn't as important as the depth. If a pot is too deep, the roots have a longer path down into the zone where they get constant moisture. This could necessitate some extra watering until the roots do reach the constant moisture.

[WaterWitchin]

I agree with Subrosa. Back in March, I repotted Psychopsis into a S/H pot that was too tall (for now). Traditional, with two holes drilled in side. I drilled the holes where I wanted them to be once established and growing larger.

I keep it in a deeper bowl, and fill the bowl about three inches over the holes in the S/H pot. When I water it, I take it out of the bowl, flush the pot, dump water in bowl, and refill to the same place. It provides the water level, or dry line if you will, at the appropriate level while its roots get longer.

I've done the same with a very large phrag and a paph. It worked well for me, thus doing same with the Psychopsis since it appears they don't like to have their roots disturbed, thus the "too large" pot.

Aloha...

[EmoryG]

Thanks for the responses. I will stick to my preferred containers/mix and watch to make sure that the mix stays moist high up in the container.

[Ray]

With 80% RH, drying too rapidly is unlikely, but if you're concerned, simply water more frequently.

The roots do not have to reach far down in the pot in order to get adequate moisture. They will eventually grow down into the reservoir, but that's a whole different subject. As an overpotting experiment, I put a 2" pot of Oncidium Sharry Baby into a s/h pot (converted florists cooler bucket) that was 12" in diameter and 20" tall. It grew and grew for about three years before throwing a couple dozen spikes and probably a thousand blossoms.

It's actually quite remarkable how long the LECA holds moisture. I went away on a two-week vacation once, and had my automated watering system fail. The tops of the pots were quite dry, and the pellets in the interior of the pot looked dry, yet were cool from evaporative cooling that was still going on, and the plants looked unaffected.