Scottish Rock Garden Club Forum
Specific Families and Genera => Amaryllidaceae => Topic started by: V_P on May 09, 2020, 06:48:59 PM
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Does anyone here have any pointers on germinating seeds of Pamianthe peruviana?
I am unfortunately in need of some troubleshooting.
7 seeds were placed on a bed of fine moist pumice on April 4. The container was covered with plastic wrap, bottom heated to a constant ~25°C and received ~16hrs/day of strong LED light. 2 seeds immediately showed themselves to be nonviable, but the remaining 5 germinated within 2 weeks.
The growth of the radicles were moderate but steady at least up to the point I could no longer see them once they vanished into the pumice, but after that the seedlings just seemed to stop doing anything, no leaves were emerging etc. At the start of May I just had to see what was going on and gently dug the seedlings up. It turned out that the radicles had penetrated a few mm into the pumice before stopping growth and turning red.
My initial thought was that the bottom heat was too much for the roots and/or that the roots were too dry (it seems people fully immerse other amaryllid seeds in water to germinate them, so I didn't think excess moisture was an issue). So I removed the heat mat and raised the water level to be immediately below the seedlings, which I now placed flat on the substrate so I could better monitor what was going on.
Since the beginning of May the seedlings have been heated from above (from the LED) to ~25°C during the day and and ~18°C (no heat) during the night. They still receive ~16hrs/day of light. However, they are still just sitting there doing nothing. The roots don't seem dead, their tips are red but they aren't rotting or contracting.
Are the seedlings too warm? too cold? Set back from me impatiently poking at them? salt burn from the (rinsed) pumice (even if no other plant I grow has issues)? light too bright (how would that affect the roots)? Something else entirely? Most importantly, can they still be saved?
It would be nice to be able to rule out each factor individually, but I have 5 seeds that were very expensive. Figured I'd ask for help from the pros.
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I have had success starting on a mix of 50:50 pumice and long grained New Zealand spaghnum In a pot in summer. they are still in the same pot and are now fairly large plants 4 years later. I just topped off the pots with some pumice
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I don't find Pamianthe particularly easy, the seeds germinate readily enough but after that, there doesn't seem to be much of a will to live; I found that the seedlings needed to be in quite a dry substrate (I'm using 2 parts perlite to 1 part peat-free compost), but like plenty of humidity around the foliage... they rot off very readily if the substrate is too damp. I live in hope that my now 5-year-old seedlings will flower this year...
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That might explain things. I've been keeping them decidedly on the wetter side. Thanks!
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Yes, Pamianthe peruviana is an epiphyte in nature & so tends to dry out quite significantly between rainfall events...
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I was aware that Pamianthe is an epiphyte, just didn't realize that even seedlings were that intolerant of moisture. It seems that many amaryllid seeds can be floated in water for germination, even if the mature plants are quite dry-loving. Thanks either way, I'll see how keeping them drier goes.