Flower Seed Packet
I purchased New York Ironwood seeds from the gift shop at Mount Vernon. On the back panel it talks about seeds requiring cold treatment. What does that mean?
Anne Arundel County Maryland
Some seeds need a period of chill/cold, called stratification, to improve germination.
This would mimic our winter period.
You can do this artificially by putting the seed packet in a zip lock bag and storing it in your refrigerator for a minimum of 2-3 months.
We find this page from the Ladybird Johnson Wildflower Center helpful: