Self seeders can get a bad name if they cross the line and become "weeds" (which is really just a loosely applied term for plants you don't want — even in the plant world, one man's trash can be another man's treasure). They can behave wildly differently in various regions. Some are invasive in some areas, but mild mannered cherished garden plants in others — so take my list with a grain of salt and use logic based on where you live. (I live in Zone 5/6 (New England).) Here are some of my favorite self-seeding plants:
Oriental Poppies (Papaver orientale) - Once these showy flowers are finished, the seed heads remain. These funny upside down cone shaped seed heads are fascinating to open up. The insides are chock full of poppy seeds (just like the ones on your bagel). Let it dry out and shake it around wherever you want to plant. I did this freely for years as a kid, much to my mother's appreciation, and we always had the most beautiful mix of shasta daisies and orange poppies in June.
Foxgloves - (Digitalis var.) - My own are the inspiration for this post. Right now, they are in full bloom and will continue to be for at least another week or two (it takes time to flower from the bottom to the top of those lanky stalks). They are also easy to manage, as you can see where they are going to grow a whole season ahead of time. After these finish flowering, the seeds will spread and those seeds will grow plants that I can move around later this fall. Actually, those new babies that will pop up through the summer are probably from seeds from last year, but the plants that grow this year, will bloom next year. (These plants are bi-ennials) I love picking off these stems, when they are ready, and by shaking the stalks around I can migrate my floxglove collection through the garden.
Nigella hispanica - "Spanish Love-in-a Mist" - I have struggled to get these going in my garden, but I love those blue flowers so much that I persist in my efforts. Maybe you have had better luck and can share a tip?
Knautia Macedonia - These dainty red heads on wire-y stems give an airy feeling to any planting group. I love to have them mixed with anything, as I think they do a great job of loosening up a planting that might be just a little too uptight.
Asclepias speciosa "Showy Milkweed" - In general I'm a fan of all Milkweeds, but the speciosa is particularly special — they are great for the butterflies and their healthy silvery leaves and big showy flower heads (that spread seeds liberally) are so fun to watch open. And when the seeds set in, you are in for a real treat if you dismantle one of the pods. These seed heads showcase the best of nature's ability to pack a big punch in a small package. The feathery stems on the seeds (that help them fly away) are packed into the pod in such an amazing way it is hard to imagine such perfection comes completely naturally. In case that isn't enough to make you love Milkweed, the shells of the seed pods are fantastic material for all sorts of fall and holiday crafts (I have a huge collection of milkweed Christmas ornaments).
Do you have a favorite self-seeder to share? Let us know where you live so we can more better sort out where your suggestion does well.
(Images: 1. daryl_mitchell licensed under creative commons, 2. Rochelle Greayer, 3. nekonomania licensed under creative commons, 4. fine gardening, 5. Annie's annuals)
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Favorite volunteers in my San Francisco garden include Verbena bonariensis, Cerinthe purpurea major, Nasturtium "Alaska" (a variegated miniature), white columbine and forget-me-nots (which have been happily reseeding from a single plant purchased in 1978).
Love the happenstance way the wind distributes these guys throughout the garden, in potted plants on the deck, as well as between patio bricks in the backyard....
My Icelandic poppies (so delicate and pretty) and columbine have self-seeded quite a bit--and it's so convenient to shake the seed heads around where I want more! I have Oriental poppies for the first time this year, so I'll have to try those!
Oriental poppies are perennial in zone 9 and can take over a garden bed, but the California Poppy (Eschscholzia californica) is a beautiful little self-seeder that never get overwhelming here. "Love in a Mist" (Nigella damascena) also throws its seeds around with lovely results, and the seed pods are amazing and last a long time when cut. I also like Impatiens balfouri http://en.wikipedia.org/wiki/Impatiens_balfourii as a self-seeder in the shade. It is fun to make the seeds fly by touching the ripe pods.
Really depends on your garden conditions. I have heavy clay soil, so I struggle to get certain cherished plants to live, let alone reseed. Need to find something that really thrives in the clay soil. I do tend to have certain wild flowers come back each year, and I get alyssum and cosmos often coming back from seeds.
Poppies are fantastic and dramatic. Other great tall/hardy self-seeders: Bee Balm, Echinacea, and Alium.
In our Madison, Wis. zone 5b garden with heavy clay soil, my favorite self-seeding plants include the following:
--Butterfly weed Asclepias tuberosa (usually very expensive so the young seedlings are a great savings and very easy to transplant)
--Purple coneflowers Echinacea (admittedly, this borders on "vigorous")
--Verbena bonariensis (an elegant and airy touch of purple)
--Bronze fennel (a favorite ornamental edible)
I see that some people have already added some of my favorites so I'll add another. Some people are hesitant to have them because of the toxicity in the seeds (then again, hello Oleander!), but castor is a great self-sower.
@MRSYOW -- impatiens balfouri!!! THANK YOU! For years I have tried to find out what these are. I remember as a child touching the pods to make them explode, but I've never known what they were. I'm off to look for some seeds to buy.....
I'd also like to add Bachelor Buttons (Centaurea cyanus) for their striking, beautiful blue flower and silvery green foliage, as well as California poppies (Eschscholzia californica) for their bright yellow/orange plums and ferny foliage. Both do well in my heavy clay soil, and have persisted despite me not having sown them intentionally for a good couple of years.
Planting alyssum seems to attract beneficial bugs and perhaps yarrow is also a beneficial bug attractant. I do believe some of the plants mentioned here are actually perennials though. (bee balm, echinacea)
I call self seeders volunteers - I think that came from my Mother. In my garden in London, Ontario, my very favourite volunteer is verbascum or mullein. The common variety is seen in ditches by the high way and is yellow. Somewhere I purchased a more gentrified white and a pink variety and they have spread via their seed all over my naturalized garden. I love the spikes of colour.
A million thanks for the photo & ID of Love-in-a-Mist! These grow (wildly) in my neighborhood & I have never known what they are. Now I can find them & plant in my own garden!
Also, please note Foxglove is one of the most TOXIC / deadly plants out there & should be planted with caution around children and pets!
Another vote for California poppies: they flower all summer for me and have been able to combat the terrible black swallow wort that my garden is infested with. They're also easily controlled if they start spreading where you don't want them: pull them individually or just till the soil a bit since they don't like their roots disturbed.
I also like dill: I think it's pretty and it's great in the kitchen.
i have had wonderful luck with evening primrose - it is considered an invasive, but anything that survives the extreme conditions of my yard [washington, dc, 13 x 17 south facing city lot]ets my vote. also, iris do very well in clay, and spread via root not seed. any other ideas for mid atlantic?
Beware Grandpa Ott -- the morning glory, that is. Lovely and robust, but a prolific reseeder! My nigellas come back year after year. Strongest plants start out as seedlings in the fall, endure the winter, and have a good head start when they resume growing in the spring. Johnny jump-ups are also delightful reseeders.