let there be light...

[Maid Spikeion]

Hello, I'm a newbie:) I've hatched out my cacti... about a hundred of them in pots in snap-lock bags! I'm very excited, but now terrified because they are about 2 months old and we are heading towards winter here in the southern hem. I want to get them a light and I've found one online and was wondering if anyone would be kind enough to take a quick look and let me know if it sounds like a winner. The air temp in the house where I'll be growing them will be 5C in the dead of winter at night, but 12C on average in the day (outside temperature goes just below freezing only a couple of nights in the winter, just until day break). The light is: "T5 FLUORO PROPAGATION LIGHT + 2 X 23" 55W, Propagation light, 4000 Kelvin Spectrum rating for growing". Do I need to put them in a box painted white inside or will they be OK just sitting on a table with the light overhead? Do I need to keep it on all the time to keep them from getting too cold?
Thank you so much for any help...

[Maid Spikeion]

oh, also, the space the cacti babies take up is about 2ftx3ft on the table...

[iann]

Getting 100% of the light from the tubes you describe would be just barely adequate for growing on seedlings through their first winter. You have no chance of doing that, but just suspending the lamp above your seedlings will lose you more than half. You should construct something to reflect back the majority of the light towards the plants. White card, mylar sheets, something. Just putting the whole lot in a corner between white walls gets you halfway there. I use a white box because it also keeps in heat and humidity. 12C isn't enough for cactus seedlings to be doing anything except sleeping, so if you want them to grow then you need to enclose the whole lot or put them on a heat pad. You want to aim for 25C by day, warmer even. 5C by night is OK for many, but some tropicals would want it warmer. Would it be simpler to let the whole lot go dormant? Seems you have temperatures most people can only dream about for storing cacti

[Maid Spikeion]

Thank you so much for your reply! Does letting them go dormant mean that they can possibly survive 12C day and minimum 5C nights inside without any lights at all?... or do I still need some lights or heat pad just to keep them alive and dormant? I don't mind if the cacti don't grow during winter, I'd rather save $ and not get lights if I don't have to. Thanks!:)