I know that some seeds need light to germinate altho I couldn't off-hand tell you which ones so I'm posting a link which gives some info. Not all on the list are annuals. I expect that if the seeds fall naturally on a thin mulch there may be enough light for germination anyhow.

I don't use a lot of annuals but do love those self-seeders whether annual or perennial. They are worth a lot in plant value altho I really need to replan my garden because I tend to let them take over.

Here is a link that might be useful: flower seeds that need light to germinate

YES! Well, in cedar bark mulch they can. I had cosmos, nicotiana, and nigella self-seed and sprout this past year through a layer of mulch.

Tracy

I was interested to read in the "Flower seeds that need darkness to germinate" link, Bachelor's buttons, Poppies and Larkspur were included. These always pop up in my garden and I don't intentionally cover them.

Libby

Hey "faltered", we live in the same zone yet half a country apart. I realize plants will act differently across the country but do you think my hulking Cosmos if left alone will self seed? I collected a few seeds just in case but this week we have had temps in the 30's and the Cosmos resemble inverted feathers or old Victorian tassels. Even though the plants looks as if the cold has killed them, will the seeds dry properly or were they stunted by the cold?

By the way,

HAPPY HALLOWEEN!

Mihai