Overwatering possible in S/H?

[Kim in CT]

I'm new to orchids and have chosen to go the S/H route.

Is it possible to overwater an orchid potted in LECA? I keep reading about cattleyas and dendrobiums needing to completely dry out before watering... One of my cattleyas is doing fine in S/H with new roots growing down into the LECA and it makes me happy every time I look at it. But my other cattleya has done nothing and is now rootless (I took a peek today -- it's been a few months). I fill up their water reservoirs weekly. Do I need to let them dry out more?

(I'm following Ray's procedure for orchid rescue -- Kelpmax soak, plastic bag, dark location -- so my fingers are crossed that it will recover.)

[SouthPark]

Kim ----- I haven't done full water culture or even S/H or hydroponics before. But if new roots (or even tips of roots in maybe some cases) grow into the watery medium and has their cells and structure adapted to the watery medium ----- and provided the temperature of the roots isn't too cold (as relatively cold and wet doesn't work well for the process systems in the roots) ----- then you probably can't 'over-water' in semi-hydro systems. The roots become adapted to the conditions.

But the term 'over-water' even for regular orchid growing is based on a reference condition. It depends on the state of the medium, and environment conditions, pot type, state of roots, temperature, humidity, air flow ----- etc.

[estación seca]

First, Dendrobiums in active growth should never, ever dry out completely. That is one of the fastest ways to kill them. Those that experience dry spells in winter don't want to be dry for very long.

Most Cattleyas in standard culture, in bark or LECA, would prefer not to be bone dry for any length of time. The warnings about letting Catts dry out are to prevent people from suffocating the roots in smaller-chunk medium. Catt seedlings should not dry out at all. In a medium with very large air spaces, like very large bark chunks, wine corks or large cinders/scoria, you can water Catts heavily, every day during the growing season. Some need a lot less or no water in winter, but most still want some winter water.

The points of S/H are that there will always, always be a reservoir of water at the bottom of the pot; and, the LECA stays moist, but still provides plenty of air at the roots. With these two conditions orchid roots that grow into the LECA are happy to remain always moist. If you let the S/H container dry out you aren't growing in S/H; you're growing in standard culture using LECA as medium. Growers should aim not to let the reservoir ever dry out.

The new roots that grow into S/H are adapted to the new conditions. You can water a plant in S/H every day, or more often. I wouldn't wait a week between waterings unless you're on vacation, or otherwise can't get to them.

The time to put plants into S/H is when they're just making new root nubs. If they aren't making new roots, don't move to S/H. It might be a very long time before the plant makes new roots, and it will struggle to take up water before this happens.

The one plant will be much happier if you water more often. The other - how humid is your growing area? If it's not so humid, I would be tempted to remove it from the LECA and put it back into a bag with some barely-moist sphagnum, until it begins new roots. At that point I would put it into S/H.

[Kim in CT]

Thank you so much!! This is very very helpful. My growing environment is my dining room, lots of light but very dry this time of year. I run a humidifier but it's trying to moisturize a large room, so I may hit 50% at times. My plan is to move my orchids outside once the weather warms up. We had snow last week!

Those dang roots. The good news is 1) I'm learning so much from this forum, and 2) root success gives me as much joy as blooms. I have my first "green tips" on some of the others and did the happy dance.

[estación seca]

There is a S/H forum here, accessible from the left yellow menu by selecting Forums. You can also learn about S/H on the Web site of its inventor at firstrays.com.

[SouthPark]

Originally Posted by Kim in CT

Thank you so much!! This is very very helpful. My growing environment is my dining room, lots of light but very dry this time of year. I run a humidifier but it's trying to moisturize a large room, so I may hit 50% at times. My plan is to move my orchids outside once the weather warms up. We had snow last week!

Also consider the temperature. There may be times of the year where some catts can have little to no growing activity - even no root growing activity - such as in cooler times of the year. Also consider cooling effects due to evaporation within the media and pot. Cold and wet can also slow things down or even hinder growing processes in roots. So heating might sometimes be required.

[Kim in CT]

This is so helpful -- thank you!

I've spent lots of time over at Firstrays.com and will continue to do so. Such a great resource!

Part of my orchid journey is figuring out what will grow in my 100-year-old drafty dining room without going to extremes, although the definition of "extremes" keeps shifting as I buy more orchids. So much to learn.

When I bought them a few months ago, I thought a cattleya was a cattleya was a cattleya. I know, right? What a noob!

Potinara Heather’s Gold ‘Motherload’ is happily growing new roots.
Rlc Amazing Thailand ‘Shogun Hawaii’ is rootless.

Maybe this makes sense based on their parentage?

[Ray]

Timing, timing, timing.

Transplant Adaptation