[gerhoe]

I was intending to grow penstemon plants from seed this coming season. The catalogue notes re the seeds...."sow and then chill for three weeks". It seems an unusual instruction. Does somebody out there know exactly the reason for that instruction ?

[Greengage]

Many seeds need to be stratified or chilled before sowing, this breaks down any inhibitors and aids germination. In a natural setting some seeds like those of hawthorn will lie dormant in the ground overwinter and germinate the following spring. Planting seeds in the ground outdoors the growing conditions often result in reduced germination. Common causes of failure would include extreme temperature fluctuations, excessively wet or dry conditions, and damage by birds, rodents or other animals