Sowing cactus seeds: best time?

[el48tel]

I have just found the instructions that Ray Allcock used to provide with the packets of seed he sold, Growing Cacti from Seed.pdf

An excellent summary of the concensus but omits reference to the more contentious issues such as time (winter etc or not) temperature (heater or not) and light (propagator lights)

It does cover temperature sedd temp.JPG

I cannot remember seeing any lights in Ray's greenhouses but he did use soil warming cables to make a large propagator I might have a picture - will have a look....

Thanks but I think I may not have made myself understood.
I meant the use of a fully defined propagator unit rather than setting the ambient to approximately the temperature.

[Bosenoge]

If you want to be exact use this: http://www.romberg.de/produkte/maximus-complete-3-0/ .
I have three of them and they work perfectly. You can set the night and day temps, everything is automatic.
My setup:
Light on for 14 hours a day
Day temp 29 (+-2) Celsius
Night temp: 19(+-2) Celsius

I keep capillary mating under the pots in the propagator-its easier to look at the seedlings this way. Baggies are less transparent. Using this method I get pretty good germination for most species of cacti.

[Jim_Mercer]

Thanks but I think I may not have made myself understood.
I meant the use of a fully defined propagator unit rather than setting the ambient to approximately the temperature.

What is the difference - a certain temperature is required either in a small enclosed space like a propagator or a larger enclosed space like a greenhouse or simply in the ground for those in warmer climates. I have had a quick look through my pictures from Ray's open days but cannot find one showing seedlings but I do know he had constructed a large enclosed space at the end of one of his greenhouse benches where this plant must have been from the heating cables

[conolady]

Am I right in thinking that some cacti, like rebutia or cintia, may like a lower germination temp? Or am I barking up the wrong tree? Maybe it doesn't matter?

[SpikyMike]

If you want to be exact use this: http://www.romberg.de/produkte/maximus-complete-3-0/ .
I have three of them and they work perfectly. You can set the night and day temps, everything is automatic.
My setup:
Light on for 14 hours a day
Day temp 29 (+-2) Celsius
Night temp: 19(+-2) Celsius

I keep capillary mating under the pots in the propagator-its easier to look at the seedlings this way. Baggies are less transparent. Using this method I get pretty good germination for most species of cacti.

Looks an amazing gadget! Built in heating mat, thermostats, circulation fan and grow lights! £200ish on Amazon is a bit beyond my price range for now though

[Jim_Mercer]

Am I right in thinking that some cacti, like rebutia or cintia, may like a lower germination temp? Or am I barking up the wrong tree? Maybe it doesn't matter?

Specfic seeds may benefit from different treatment, that is always the problem with generic advice

[el48tel]

Jim_Mercer
Please excuse this pedantic oldie .... but one old hand did say to me that a propagator unit held its humidity whereas a heated tray didn't when I asked the difference.

[el48tel]

Am I right in thinking that some cacti, like rebutia or cintia, may like a lower germination temp? Or am I barking up the wrong tree? Maybe it doesn't matter?

Specfic seeds may benefit from different treatment, that is always the problem with generic advice

And is that the cause of confusion? Different experts with different experience growing different species with different needs .... and the rest of us working in the dark.

[SpikyMike]

Jim.....a propagator unit held its humidity whereas a heated tray didn’t....

Is constant humidity level for cactus seedlings a good or a bad thing? Thx

[el48tel]

Jim.....a propagator unit held its humidity whereas a heated tray didn’t....

Is constant humidity level for cactus seedlings a good or a bad thing? Thx

Damned good question to which I too would like an answer. Reading some of the cultivation notes from around the world ... some indicate to the affirmative ... others indicate it as a source of problems.