Temporary shade

Thanks, it was only intended as somewhere to grow on phals from indoors that had finished flowering, but those little phals looked so neat and made the case a nice feature.

The main greenhouse is kept frost free at 3-4deg C overwinter, though because I have 10mm polycarbonate* it only cost a few pounds in electricity to do that in these mild winters.
( * was glass until the footballers got going!)

The case is kept at a minimum of 15c for the phal orchids and am experimenting with a 180w tubular heater at the moment, all controlled by an Arduino micro I have programmed up.

 

@ricky101 - ahhh Arduino! Handy for that sort of thing... Since they have so many analogue inputs and digital outputs you could also use it to control humidity by switching one of those little ultrasonic vaporisers on/off.

@hydrogardener - thanks for that info - unfortunately I have found that the bark I can get hold of is not good enough, and in UK it is getting very difficult to get hold of large grade perlite. Your orchids look to be in fantastic condition. I have bought seedlings in flask before, but find them very hard to bring on - so kudos to you for getting into seed propagation!

 

Yes they are handy for quickly knocking up a controller, I'm also using a humidity sensor and when the case is closed its always been quiet high , up to 95%, so no need to additional foggers yet.
Also have saucers full of Hortag clay pellets in water to add to the humidity when the vents are open.


Re your potting mix problems, have you joined in the orchidforum.eu , its really a uk site , a good and interesting place for all types of orchid and their care.

 

Hi @ricky101 - thanks for forum info. By checking them I have found out that bark sold for reptile keepers is same as orchid bark, and it seems to be more readily available (and cheaper) by searching for 'reptile bark' on ebay! However no-one seems to have a solution for the lack of perlag/hortag

 

Better correct my above post, the clay pellets I referred to as Hortag are actually HyrdoLeca.

Now, as far as I know, I think they are one and the same .. yes ?

If so, then Hydoleca is available quiet cheaply from many places, picked up a 25lt bag for £5 last year from a garden center.

As for perlite, have to ask, what size is 'agricultural grade' ?

Can only find coarse grade in the UK, specified as 5 to 10mm at one supplier and 8mm at another.

ps - any pics of your orchids / vandas - they seem to be quiet hard plants to grow given our local conditions / light levels.

Did try the odd vanda when I grew orchids in a larger area some years ago, but without success.

 

The topic at this month's meeting of the Northeastern New York orchid society meeting was growing orchids using a semi-hydroponic method. It is a simple inexpensive method of growing orchids and once the plant is established it is virtually impossible to overwater the plant, as it will be accustomed to growing in water.
You can use any container without holes in the bottom, however, I prefer clear plastic food containers so I can see what the roots are doing, and, more importantly, you can see when to water/feed.
Two 1/4" holes are drilled about 1" above the bottom of the container to form a well. Most growers use expanded clay pellets to grow the orchids, so that is what I am using as I also have a lot of them available.
The pellets are pre-moistened and added to the container so that it is a little more than half full before the plant is added. The plant is not adapted to growing in liquid yet, so you want any roots left on the plant to be above the bottom not touching the liquid.
It is best to start with a young plant that does not have a large established root system. Before placing the plant in the container any dead or damaged roots should be removed, as they will rot. The plant is placed in the container and the pellets are added to fill around the plant up to the brim.
At that point, you place a strip of tape over the holes and fill the container with a quarter strength nutrient solution and let the plant soak in the solution for an hour. After an hour remove the tape and let the liquid drain from the container, leaving the remaining liquid in the well.
That's it, you are good to go. The pellets will wick liquid up to the plant from the well. When the liquid in the well is almost gone I replace it with more quarter strength nutrient solution and let it overflow. On every fourth cycle, I flush the container with clear tepid water to remove excess salts from the pellets.
As I have been growing vegetables hydroponically for several years I decided to try a few orchids using the semi-hydroponic method and so far I have been impressed.
As a trial, I have identical plants, one growing in bark and one being grown semi-hydroponically, and it should make for an interesting comparison.
There are a lot of videos on growing orchids using this method on youtube.com if you are interested in trying this method.