Well i have actually tried this .. the esky thing that is.

I got an old esky and mounted lights in the lid. Instead of fluoro tubes i used those fluorescent, energy saving type bulbs that you can stick in a regular light socket. These are good because theyre small (i easily fitted 4 into the lid), and as i recall theyre more efficient than ordinary fluoro tubes (in terms of lumens /watt). I used 4 x 20w for starters. Name brands such as philips seem brighter than el cheapo ones for the same wattages. I used 20w philips ones - the tube is a tight spiral so theyre small, and they're bright.

To actually fix the lights to the lid i bought 4 light sockets ..the ones that just mount onto to something flat and are held on with a couple of screws. I think theyre called batten mounted light sockets or something like that. Wiring them up is pretty straightforward. I just drilled a hole for the power lead and that was it.

When the lid was closed practically no light came out of it and it looked just like an old esky. The problem was that not much heat could escape either and it got really quite hot from the bulbs in there. I tried with fewer, weaker bulbs etc but when the lid was closed it still got too hot. Leaving the lid propped open fixed the heat problem but then of course theres light everywhere and high humidity is lost.

So next i mounted a small computer fan in a hole i made in the side of the esky and drilled a few small holes in the lid. This way (when the lid was shut) the fan blows air out the side while sucking in new cooler air thru the holes in the lid. I could have had it the other way with the fan blowing in cool air, but i had cuttings in there and i didnt want a draft on them. However with small plants the fans blowing air in and it then goes out the top.

To maintain humidity i put wet sand in the bottom.

It works well for cuttings and small plants. One or two 15 - 20w bulbs seems adequate but i guess it depnds on what youre trying to achieve. Plants grow really well in there and can go a dark green. Ive never tried it with cacti but i think i will.

So it works but overheating can be an issue. There are prob a variety of other ways of gettig around that apart from a fan though i reckon. Maybe a piece of glass etc over the top instead of the lid, with the lights outside.

Oh yeah the other thing is that it can get crowded in there. Bigger the better for the esky i think.

Hey charlie,

This will work but only with small seedlings. The problem is there is no air circulation and this will cause all sorts of fungal problems. Your better off using metal shelving from bunnings (its cheap) and attaching a fluro to the top of each shelf. I have been used this for a while and it works pretty well.

maybe I can rent out space in my propagator ! cactus on agistment . chuckle chuckle

Well at this stage I'm holding off on wiring up an esky... frankly, whilst the idea probably has merit, I think it's a bit much effort. In the meantime, I've improvised a humidity tent over my Pereskiopsis cuttings outdoors and it seems the improved heat, light and humidity is doing the trick.

As an update to this whole mess... it seems the humidity tent (also known as a clear plastic bucket with a plastic bag on top) has done the trick. My Pereskiopsis is now growing like a weed. Yay!

hey Lachy thats my current 'humidity chamber' too!

i found that without a greenhouse or propagator pereskiopsis doesn't seem to grow overly super fast here, for me anyway.
I think it likes high humidity not the dry air we have here. (our low humidity is incidently better for alot of the more sensitive mexicans etc).
Heat, plenty of water and heaps of fertilizer of course help to produce a faster peresk growth rate too. they like semi-shade positions during the warmer months too (that, or like most things they just can't stand up to direct scorching southern summer sun!)
As an experiment I'm going to grow a peres in pure vermiculite with added slow release ferts and then liquid feed and water the living daylights out of it and see what happens. anyone grow pereskiopsis in an elaborate hydroponic setup? like substitute the tomatoes for pereskiopsis grafts... i have wondered about this before.

i have been thinking of buying an old second hand bain marie and covering the elements with sand... this way i get the lights the heater and the glass chamber!!! what do you think? surely we can pick these things up cheap somewhere

I think you would have cooked cactus darren. The thermostat will need to be replaced since the lowest setting will toast your seedlings.
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