While in the Berberidaceae realm, here’s a post where I outlined as best as possible, the process of growing Podophyllums from seeds from A to Z.
The Chinese Podophyllums (syn. Dysosma), share similar seeds and germination requirements as our native Podophyllum peltatum (mayapple). In all cases, the seeds are enclosed inside fleshy fruits. After the fruits are collected, it is important to extract and clean the seeds right away. This can be a bit unpleasant because the inside containing the seeds is gelatinous (use a sieve and lightly rub the seeds out and rinse, rinse and rinse again).
The sowing can/must be done right away (Sept./October) or the seeds placed in moist vermiculite in Ziploc bags until sowing. They are easy to keep in moist vermiculite as long as were well cleaned; you only have to check the moisture level once in a while (one exception noted for Dysosma aurantiocaule, when the seeds got soft fast, but I had a small lot of seeds and cannot really generalize).
I must emphasize that these seeds are hydrophilic, and using dry seeds to sow, in my opinion, is a complete waste of time.
The required cycles for germination are: Light WARM (late fall temperatures)/COLD.
- Sowing outside: the time would be early to late fall; sow as usual in pots/large containers, water and keep them over the winter in a cold frame. Easy done, no worries!
- Sowing indoors: usually done in the winter/early spring with seeds that have been kept moist and allowed a light warm/cold period. The cold period can be provided in a cold garage/fridge. It is not advisable to use this method unless enough light can be provided for the growing seedlings (light stand, conservatory).
If someone wants to speed up the process, the Ziploc bags with seeds can be taken out of the fridge around late January/February and kept at room temperature; gradually the seeds will start to germinate and can be potted up one by one and placed under the lights.
Or, leave the Ziploc in the fridge until all seeds start to germinate towards spring (approx. March/April) – as well, pot them up and provide adequate conditions until they can go outside.
In most cases, only cotyledon leaves will be formed, in other cases the true leaves will appear as well. Usually, P. peltatum forms only cotyledon leaves in the first season; the Chinese ones are variable, most will form a true leaf. When growing from seeds there is always great variability.
Keep the seedlings in a part shaded place, water and feed lightly. At some point in the summer they may go dormant, especially if very hot weather.
All the seedlings which didn’t form a true leaf in the first year, will do it in the second year. Be patient. In general, 3-4 years are necessary to obtain a good young plant; they will grow really fast after the root system has bulked up.
Synopodophyllum hexandrum (syn. Podophyllum hexandrum)
The difference in this case is that the seeds are not hydrophilic, so they can be kept dry in the fridge for quite a few years. Of course, when sown fresh (fall), they will germinate in the spring.
For dry seeds, a GA3 treatment followed by sowing at room temperature usually will result in rapid germination, and sometimes most seedlings will present the true leaf.
Important for all species: in the first 1-2 years they put lots of energy into forming their radicular system; this translates in the fact that the seedlings need enough space to develop. So, either sow fewer seeds per pot or transplant them in the early stage in individual pots.
I think my pictures show very well what I mean; learn from my mistakes ;) If you sown to dense and didn’t prick them early, don’t panic; when still dormant (very early spring), shake the soil, untangle the roots gently and repot in a fresh mix in large size pots.
Again, there is always variation when growing from seeds; we cannot expect all the seeds, even from the same batch, to grow the same: the collection site, mother-plant, ambient factors, all have an influence in germination & growth of the seedlings. This picture with one year old Dysosma plants shows it very well:
I hope this will be helpful for all wanting to grow Podophyllum/Dysosma from seeds – Happy Podos growing!