Growing Jeffersonia from seeds

I’ve repotted some fine young Jeffersonia seedlings two weeks ago and now it took me a great pleasure to write this post. Jeffersonia diphylla (Twinleaf) is a wonderful NA species that should be mandatory for all gardens; the pictures show it in its glory at Aspen Grove Gardens.

A delight from early spring (April) to fall, and notice that although a woodland species, it is grown with a fair amount of sun and does very well.

Just like bulbous/tuberous species, the ones that form rhizomes need 2-3+ years to develop their root system before they will start flowering. The faster/better their rhizome grows, the sooner they will flower. Again, it is very easy to underestimate the size of a seedling root system. This is why the repotting is very important and can be done either in the fall or spring. Each period has its pros and cons, but for our climate at least, I incline for the late fall (after they’ve gone dormant).

 I will outline next the whole process from sowing to repotting the seedlings:

• Sow the seeds as soon as possible after collecting, or keep moist at room temperature; however, keep in mind that this species doesn’t keep too well in moist storage and seeds are available (if) for a short period.
  
• Sow as usual or use my ‘space saving method’ – also very practical for someone who doesn’t want to have one pot sitting around by itself. Sow all the seeds in one larger pot and ‘plant’ the pot in the ground (in late fall I added some mulch on top, which I’ll remove in the spring).

Tip: ‘plant’ the pot close to a shrub/tall perennial plant that will shelter and shade the seedlings; also close to the house so you won’t forget about it (the seedlings require extra watering during dry spells). Mine was close/beneath an old Peony, unfortunately I don’t have a picture.

• Seeds have germinated somewhere in May (about 100% by the look of them). Foliage wise, not much it will happen the whole season, only one shoot with the cotyledon leaves.

Jeffersonia diphylla seedlings

• Use a diluted fertilizer once in a while (only if you remember…), water regularly; nothing else to do till late fall.
  
• By late October- early November watch for signs of dormancy.
• Let the pot dry out a bit.
• Tip off the whole content and gently separate the seedlings (don’t forget to congratulate yourself, take pictures, eat some chocolate/cake…)

Jeffersonia diphylla: one-year old seedlings ‘extracted’ from the pot

• Repot in a fresh potting mix (I don’t have any ‘special’ formulas); one or more seedlings/pot. Planting 2-3 seedlings/larger pot will make a ‘clump’ faster.
  

Jeffersonia diphylla seedlings showing an extensive root system after one season of growth and a well formed bud.

• Water well, and if it’s late November, that’s all they need.
• Storage: cold frame, or again, ‘plant’ the pot(s) in the ground and throw mulch/few leaves on top.

Jeffersonia diphylla: repotted seedlings ( I have 2-3/pot)

• Another good option is to grow them one more year in the same pot; this way the seedlings will be larger in size and easier to handle, especially for those who are not used with transplanting little seedlings.

Special thanks to Robert Pavlis @ Aspen Grove Gardens, for growing this beautiful, ‘photogenic’ species and providing the material for this post, i.e. the Jeffersonia seeds :)

You can apply the same technique for growing its Asian counterpart, Jeffersonia dubia. Next to come – how to easily grow from seeds Aconitum alboviolaceum…stay tuned.