Explanation of Semi Hydro Orchid Growing
 

I'm new to this forum so apologies - I'm sure I just haven't looked in the right place. :waving (this smilie is me tapping dust out of my ear rather than waving :) )

I'm really interested in the concept of Semi hydro orchid growing but I can't find an explanation of exactly what semi hydro growing is & what is needed to set it up. I'd love a pointer in the right direction!

Many Thanks

As the originator, I have a ton of info on my website.

Many thanks for this Ray, I'll have a look!

I want to say a big "Thank You" Ray! I am just getting into orchids and have jumped in with both feet. I have everything ready to put most of them into S/H set-ups but have been really nervous because all of the information I have seen always says "depending on your conditions". I live in SE Texas right off the gulf so I am thinking our conditions are very similar differing only in that I probably won't get so cold in the winter. Since all my plants are in the house that shouldn't matter, right? Really excited to see your Oncidums in S/H because I saw a video saying it didn't work so well for them.

Yet another testament to how deceiving or downright wrong videos can be, and how a well-meaning "conclusion" might not apply to "your" situation at all.

When I was developing semi-hydroponics, I grew in a warm greenhouse in PA. Now that I am in coastal, southeast NC, and have no greenhouse, I have to contend with very warm, humid summers, and moderate but dry indoor conditions in winter. I have, therefore, limited by collection to plants that can deal with both, and no longer grow my phalaenopsis in S/H due to the evaporative cooling in the dry indoors. My paphs and phrags, on the other hand, are doing great.

Living here in Northern Midwest and in a turn of the century house, would it be feasible for me to do S/H? Or would it chill the plant too much due to the combination of evaporation and the cooler air temperature in the house especially on a very cold day/night below zero (not counting the windchills)? There are days in January/February some winters that it gets mighty chilly in the even in the house with the boiler working overtime trying to keep up.

I have an Oncidium being shipped to me tomorrow for free as the seller went to ship it and found the main bulb shriveled. She is shipping it bare root and I was wondering if it would be okay to put it right into SH on a heat mat?

That's going to depend upon what type of plant you want to grow. Stuff that likes it hot won't like the cold, wet feet.

But then again, many orchids wouldn't like that, no matter how it's grown.

---------- Post added at 08:55 AM ---------- Previous post was at 08:43 AM ----------

Certainly, but with the following caveats

• The fact that the plant is shriveled tells me you are starting with a weakened plant in the first place.
• No doubt the roots will not be great, and certainly wont be optimal for S/H culture.

Taken together, that lessens the chances of an easy conversion, but don't give up hope.

Any time you repot a plant, it stresses it, so don't think that getting it established in bark now is a better idea, then switching it later. That merely doubles the stress.

Soak the bare-root plant in KelpMax solution (1Tbsp/gal) overnight. Pot it up and water it in with that solution. Invert a clear plastic bag over the plant and pot, and place it on the heat mat somewhere shady (any direct sun will result in a "broil in bag" situation. The next two times you water it, use the KelpMax. After that, plain water only until new roots start growing into the medium.

Perfect! I will do exactly that and keep my fingers crossed!
Thank you Ray!

I live in northeastern Kansas in a house built in 1907. Fifty some windows total, all but three original to the house. Pretty much all my orchids are in S/H. Most stay in the basement all winter, under lights. Unfinished basement with thick stone walls. Temps at night go below 60, daytime 65 to 68 depending on outside weather. Around end of December I put an electric heater in that area, and it runs at 68 during the day and is off at night. I grow/bloom Catt, Bulbo, phrag, paph, Blc, Zygo, Onc, Tol, Cymb, Psychopsis, etc; in other words, wide variety.

There's a fan, a mist system over certain (a vanda, Tolumnia, etc) that goes off for 30 seconds three times a day. I've yet to have a problem heatwise. Having said that, I've killed orchids over the past twentysome years. Likely the ones that couldn't stand my culture of them.

Oh... and I keep phals upstairs for the most part, other than the few that are mounted. When I kept them in the basement I used a couple of seedling heat mats. They live upstairs now because I have a place for them that nosy dogs can't reach. Upstairs temps 68 day, 65 night.

Short answer: Why not give it a try?