Sheldon wrote in
ps.com:

On Jun 18, 9:37?am, FragileWarrior
wrote:
Wallflowers set their seeds the same way do: in little tubes that
line the spent flower stalk.

When is a good time to collect the seeds? Can I cut the stalks now
and hang them to dry or do they have to come to a certain state of
ripeness while still on the living stalk?

I was wondering if I should collect them now before it rains today.
(At least I hope it's going to rain today.)

I would wait until flower heads are dried on the plant. I don't
understand what it raining today has to do with anything...

I didn't want the rain to trigger seed pod popping like it does with
Impatience sometimes.

I assume
it will stop raining, the sun will appear, and things will dry. Like
other wildflowers wallflower is a plant that reseeds itself. There
should be a fairly large window of time for harvesting seeds and not
all will ripen at the same moment... take seeds in progression as they
dry.

Okay, but if they dry in the garden don't they also begin to drop at that
point? I wanted to get the seeds to share with some friends and to seed
a new bed hence the desire to get them before they pop.