CactiGuide.com

Hi all,

I recently found this website/forum and its been a great source of information for growing cacti and succulents. I recently started my first batch of seeds of various cacti and so far so good, nearly all of my seedlings have sprouted within a week. My astrophytum have been the fastest and most successful germination with an almost 100% rate of germination. They are getting considerably bigger and I was wondering when would be a good time to start opening the zip lock back that they are germinating in. I know I should open the bag in small increments but I'm not exactly sure about the time frame as to when I should start the process.

What time after the astrophytum seedlings have germinated should I start acclimating them to a more dry environment?

Thanks for all the help and info in advance!

You can start as soon as germination of done HOWEVER the longer you leave them in high humidity the quicker the growth rate will be compared to open air. I personally tend to remove humidity at 2 month mark at the latest however many growers leave them for 6+ months. Last year I removed from high humidity after 1 month from germination due to mold issues.

LateBloomer wrote: ↑Wed Apr 13, 2022 4:41 pm You can start as soon as germination of done HOWEVER the longer you leave them in high humidity the quicker the growth rate will be compared to open air. I personally tend to remove humidity at 2 month mark at the latest however many growers leave them for 6+ months. Last year I removed from high humidity after 1 month from germination due to mold issues.

I think I'll go with 2 months as well, but like you said it's all dependent on the mold growth. I didn't sterilize my soil but I did add mycorrhizal fungi to the soil and covered the seeds with it at well, hoping the good fungus will choke out any bad fungus. The roots of the seedlings are definitely looking like they took well to the mycorrhizal since they're coming out with sooo many hairs, but fingers crossed that works and I can leave the seedlings in there as long as possible

You can always open the baggy and spray h2o2 and close again… many that keep it closed 100% pre sterilize… I don’t so I open and mist h2o2 at 3% if needed. Doesn’t always work…

you can used a very diluted bleach water solution as well without killing the seedlings. Like 30mL per liter… that’s very low concentrate but should help control some mold… I don’t use bleach just something I’ve seen some growers use.

Astrophytum have relatively large seedlings which don't do well in bags for extended amounts of time. A couple months to get their roots down is sufficient, and any more is likely to incur losses. Generally my rule of thumb is to take them out when they are about pea sized. That's quick with astros, but could take 5 years with strombocactus.

Great tips!
Can anyone share your Astrophytum seedling image?
Recently, it is the flower season of this species, and I also harvest lots of seeds. They are indeed really big, compared to other cacti.

As soon as possible Astophytums rot easily. It slows growth down and but I've rotted too many so I'm very cautious now. I bottom water to keep them from drying . Much easier to grow from seed in AZ where the air is always super dry.

Astrophytum coahuilense is the hardest it rots easy right after germination the other species are easier from seed but still rot.

I kept the last portions of seedlings from March to November. I would keep them longer, but I needed space for new pots with sown seeds. It was astrophytum, escobaria, lophophora, ariocarpus epithelanta....