Sowing cactus seeds: best time?

[Jim_Mercer]

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.

As a very pedantic oldie you have two different variables - heat and humidity.

Some people like to seal their pots with sown seed in plastic bags and maintain a high humidity so the heat source does not matter for them


I used to use a heated tray that could accommodate three standard seed trays. I normally had the clear plastic tops on the trays but took them off for this photograph

[Phil_SK]

High humidity is both a requirement for young [cactus] seedlings (they usually dry up to nothing without it) and a problem (it's ideal conditions for competing organisms - moss, algae, fungi).

I think you can look too hard for 'rules' of how to grow plants from seed. Most C&S seed needs light, moisture and moderate warmth (possibly fluctuating) to germinate. To keep the young seedlings alive long enough for them to reach an age where they can fend for themselves is a bit tougher. They need more light (ideally pretty bright light), good humidity, steady moisture at the roots and, again, moderate warmth. Cactus seedlings tend to need humidity for quite a bit longer than most of the other succulents. There are lots of strategies for providing heat, light, humidity, moisture and it's inevitable that every grower will have their own methods that differ from one another: there isn't just one template that everybody sticks to using the same set of kit or timetable.
The pitfalls, in my experience, aren't with germination but with keeping the youngsters alive, principally, providing enough light without causing them to overheat, especially as the sun grows stronger in the springtime, and helping them to survive moss, algae and fungi.

[gerald]

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.

This is always a problem whatever you cultivate. You can look into it scientifically, but expect a lot of jargon, detail and complexity if you're not used to reading scientific papers.

Or you could ask the professionals, but obviously not only do they tend to keep their methods to themselves, but they have professional equipment and chemicals that the amateur can only dream about.

Disregarding cacti for a moment, this blog can be an interesting read:

https://www.gardenmyths.com/

[iann]

Tomorrow is the best time. That's when I'll be sowing mine. Friday nights are a real party at my house

[Jim_Mercer]

Here is an article that I came across while trying to find a picture of either Ray's or my propagator (used in Branch newsletter many years ago with some of Ray's findings on lightweight growing media). What is missing from these instructions is that the crushed brick should not include any mortar, especially if your source is an old house where lime mortar was used

Raising seedligs.pdf

(60.28 KiB) Downloaded 118 times

[el48tel]

Here is an article that I came across while trying to find a picture of either Ray's or my propagator (used in Branch newsletter many years ago with some of Ray's findings on lightweight growing media). What is missing from these instructions is that the crushed brick should not include any mortar, especially if your source is an old house where lime mortar was used Raising seedligs.pdf

Again - makes sense - just doesn't say "when"

[el48tel]

Tomorrow is the best time. That's when I'll be sowing mine. Friday nights are a real party at my house

Chuckle!

[el48tel]

.................. To keep the young seedlings alive long enough for them to reach an age where they can fend for themselves is a bit tougher. They need more light (ideally pretty bright light), good humidity, steady moisture at the roots and, again, moderate warmth. Cactus seedlings tend to need humidity for quite a bit longer than most of the other succulents. ............................
The pitfalls, in my experience, aren't with germination but with keeping the youngsters alive, principally, providing enough light without causing them to overheat, especially as the sun grows stronger in the springtime, and helping them to survive moss, algae and fungi.

Agreed - and learned the hard way so far

[Nick_G]

Here is an article that I came across while trying to find a picture of either Ray's or my propagator (used in Branch newsletter many years ago with some of Ray's findings on lightweight growing media). What is missing from these instructions is that the crushed brick should not include any mortar, especially if your source is an old house where lime mortar was used Raising seedligs.pdf

Again - makes sense - just doesn't say "when"

It doesn't matter when, any time between now and the start of June will produce seedlings big enough to survive a cold winter rest between October and the following March.

Most cactus seed (with a few exceptions) is as easy to germinate and grow on as cabbages. Don't over think it.

[el48tel]

Here is an article that I came across while trying to find a picture of either Ray's or my propagator (used in Branch newsletter many years ago with some of Ray's findings on lightweight growing media). What is missing from these instructions is that the crushed brick should not include any mortar, especially if your source is an old house where lime mortar was used Raising seedligs.pdf

Again - makes sense - just doesn't say "when"

It doesn't matter when, any time between now and the start of June will produce seedlings big enough to survive a cold winter rest between October and the following March.

Most cactus seed (with a few exceptions) is as easy to germinate and grow on as cabbages. Don't over think it.

Thanks - again that makes sense - especially the thought of seedling survival