New to semi-hydro - my experience so far

[flowerpower]

Hi all. I thought I'd share my experience of growing my orchids in S/H, lessons learned so far and how my orchids are doing. For us newbies to S/H it can be a very worrying time when we first start this method - from what I read, I expected my plants to instantly succumb to root rot and die! Apologies in advance for the long post.

I have 4 onc's and 2 dendrobiums (nobile-type) in S/H for over a month now.

I converted these to S/H after the bark they were in broke down rapidly this summer (only 3 months). The room they are in gets very hot in summer and cool in winter (converted attic). The water requirement of these orchids was very high in the heat and the fine bark I chose was breaking down from the watering and heat after only 3 months. I noticed there was also insects had somehow appeared in the media - obvious sign the bark needs changing. I decided that the watering needs were high so semi-hydro might be a good solution to help save time and prevent media breakdown.

This is my set up so far:


The first oncidium is an intergeneric with 2 flower spikes from its pre-SH days. It is a Tahitian Dancer Pink Fairytale. The tag said Goodaleara but I heard its reclasssified as Aliceara. This orchid, from day 1, has been one of my best growers. It did get accordion pleating in the summer heat pre S/H but despite some issues with that, it has been such an easy orchid. It is perfect for a beginner like me - the bulbs stay plump and it produces roots rapidly. The new growth is not pleating in S/H (so far, so good!).



Looking at the roots, this orchid has not had any problems converting so far. The 3 new growths are also growing smoothly. However, I do have a residue - white powder - building up on the actual plant (possibly fertiliser but I have been using it quite diluted). This is a very fine-rooted oncidium but is doing very well. The only problem I faced in the conversion is that, while it has lots of roots, they always remain short on this orchid. It is almost just "sitting" on the LECA. However, it does not seem to mind.



The next oncidium is a Sweet-sugar style yellow one. I bought it with zero roots. I never expected it to survive. It has severely wrinkled back bulbs from its days with no roots. I recently popped it into semi-hydro. It has some roots now and the new growth is magnificent in comparison - I am hoping it might even spike! It seems to like S/H and is holding its own. It is quite a mature bulb but is still producing some new roots so I went ahead and put it in.



The next two oncidiums are both intergeneric NoIDs, they are large and have thicker roots. Neither did very well for me in bark. This one fell apart during repotting into two sections. I decided I wanted them to stay together so they are potted back-to-back in S/H. Luckily both parts have new growth. I have never been able to keep these pseudobulbs plump. They looked equally terrible in bark so I will keep going.



Another similar large-rooted oncidium similar to the Heaven Scent Onc's (it's a NoID), this one doing a bit better because it stayed intact. Some wrinkling but not much worse than when it first went S/H. New growth well on the way.



The last two are my den's...



My Den's are both nobile hybrids and I partially regret moving them to S/H for three reasons.

First, I foolishly put them in S/H when there are no small new growths, the growths are already maturing . The canes are a bit short but I do not mind as they did remarkably well to grow as much as they did. I bought them flowering in mid-summer a bit out of season for them. I am hoping for better canes next year where I will push them harder with fertiliser next year.

Secondly, I had problems with staking. I did not want my bamboo stakes to rot in the reservoir so I had to improvise slightly by taping the stakes to the side of the pot......



The third reason I regret putting them S/H is that of the winter rest for these orchids that want to go dry. I am really not sure how to manage that in S/H. I know the options are to dry them out or keep the reservoir filled but no fertiliser. I do not fertilise these at the moment but do water as the canes are not quite finished. I have adapted my S/H for the den's by keeping the reservoir full for a week and then draining it and letting them dry a little bit (I have no prospect of new roots for a long time so need to be a bit careful). I also read a post from Ray that Den's tend not to do as well as other orchids in S/H.

My reservoirs stay full for quite a long time so it has been overall an easy way of maintaining these orchids. When spring and summer comes and temps go back up I'm hoping to see some good growth.

It remains to be seen whether I will continue my Den's in S/H. I am going to leave them for now with the currently treatment and perhaps put the S/H full force in spring, when the new growths start. If anyone else has grown these in S/H I would love some tips. I will be starting their dry rest when they finish their canes in the next few weeks. I plan to leave the reservoir empty. I am already seeing some leaves yellowing here and there so I am pleased that they seem to know they are getting ready for winter.

Let me know what you think of my set up and apologies for the long post. If you have any criticisms or ideas to improve their care I would love to hear your thoughts.