Hello
I found a photo of Thalictrum seed in a plastic box...your's look like this ? Photo ?
With the plant
I have found this recommandation !
Sowing: Sow February to April / August to September.
Sow indoors in pots or trays at 13 to 16°C (55-60°F), ‘Just cover’ the seed with vermiculite or sieved compost. Sow in trays containing John Innes seed compost, or some similar free draining compost. The compost should be kept moist but not wet at all times. Germination should occur between 15 to 21 days. Thin (prick out) to 7.5cm (3in) pots when seedlings have developed 2 proper leaves and are large enough to handle. Gradually acclimatise to outdoor conditions for 10 to 15 days before planting out. Space 45cm (18in) apart.
I hope you're interested in.
You've not some seed to exchange with me ?
I've Thalictrum aquilegiifolium in my garden but not seed this year.