I've been designing a new flowerbed and I ended up choosing a lot of annuals instead of just sticking to perennials. I've never really grown annuals, and when I started to research them, I ended up with a lot of conflicting information. What I would like to know is: is it true that they will reseed on their own each year, or is that only true for some of them? I've grown zinnias and they've always reseeded for me, but other than that I have zero personal experience with annuals. Also, has anyone tried any of the following in my area (southwest Missouri), and have they done well? (All of these are out of the Burpee seed catalog) Victoriana Mix dahlia Spring celebrities dwarf hollyhock strawflower Doubletake cosmos snapdragons hollyhocks sweet pea verbena rudbeckia Any advice would be great! Thanks!!
They will reseed in a natural setting, but deadheading seems to prevent it. Several of the plants you mentioned (strawflower, snapdragons, hollyhock, rudbeckia, and cosmos) do well in northwest Ohio, so if the conditions are very different they might not do well for you.
Some annuals will self-seed some will not. You can harvest the seeds from those that do not and plant them in the spring...unless the seeds are sterile or plant will not come true from the seeds as would be the case in some hybrids. Zinnias are great self-seeders as are most types of Cosmos. I have never had any luck with Snapdragons self-seeding at all but most of our winters have been mild enough that they stay green year round. Some Verbenas are perennials and some are annuals. Rudbeckia is a perennial up to zone 3 so you won't have to worry about them at all.
I don't know about other Cosmos varieties but these two have returned in mass quantities in my yards since I planted a packet of mixed wildflowers 5 years ago. I don't think I could get rid of them if I wanted to, they are very prolific Kind of makes me afraid to plant other types of Cosmos for fear that is all I would have in the gardens in a couple of years. Cosmos sulphureus (Sulphur Cosmos, Yellow Cosmos) Cosmos bipinnatus (Garden Cosmos, Mexican Aster)
I believe that what I have may have been Cosmos bipinnatus. Probably the climate difference makes the change between it being all over the yard and it not reseeding.
