May 6th, 2009
Saving Bluebonnet Seeds

Bluebonnet seeds are ripe when the pods turn brown and you can hear the seeds inside rattle.

I had a question recently on gathering bluebonnet seeds: how do you know they are ripe? It’s pretty easy to tell. When the shells turn brown, tap the shell. If you hear the seeds rattling inside, they are ripe. However, wait too long and the shell will explode when you tap it, throwing seeds everywhere. Lying in a field of bluebonnets on a hot May day, listening to seedpods pop is a classic Texas summer pastime.
photo: bluebonnet seeds
Ripe bluebonnet seeds open with a pop and a twist to disperse their seeds.

If you want to start bluebonnets in a new spot, you can cut whole ripe stalks (like the one above) and let them seed themselves in their new home. This is the easy-going natural method of seeding, great for wild areas. It might take several years to get a good stand going. That’s because bluebonnet seeds have coats of different thicknesses. Some wear thin and sprout the first year. Others take several years. This is a survival tactic to ensure that all the seeds don’t sprout at once, only to be lost to bad weather.

photo: bluebonnet seeds
Bluebonnet seeds ripe versus unripe. The green ones are NOT ripe and will rot if you try to plant them.

People tend to want all their seeds to sprout together, so commercial seed providers sometimes wear down the coat with an acid bath. People who gather their own seeds gently sand the outer coat down a little, just enough for water to soak in. I don’t do any of these things. Don’t need to. After a couple of years of growing bluebonnets, I’ve always had too many sprouts each fall. Individual plants (which contain multiple flowers) grow like small bushes to about 18 inches tall and two feet in diameter. In a small garden, you don’t need very many. I deadhead them to encourage more flowers and only let the best go to seed.

When you’re ready to clear out the bluebonnet plants, don’t pull them out by the roots. Cut them off at ground level. The roots are covered with nodules containing nitrogen-fixing bacteria. Not only are bluebonnets beautiful, they enrich our soil.

ripe larkspur seed
The same seed-saving advice holds true for larkspur (pictured above), nigella, and poppies. Wait until the pods are brown and the seeds are hard enough to rattle when you shake the pods.

If you have meadow plants in your garden, letting them go to seed means letting the garden look a bit messy for a few weeks. You’ll quickly understand why the word “seedy” means shabby and squalid. The payoff is a hundreds of free self-sown plants next year.

by M Sinclair Stevens

16 Responses to post “Saving Bluebonnet Seeds”

  1. From Jenny Austin:

    Informative post. We are on the same track. I pulled out the bluebonnets in my front and sunken garden and they are lying on the driveway drying out in the sun. Each day I go out and cut off the brown ones before they dehisce and put them in my brown paper bag. That way I have plenty to put out in new places in the late summer. Otherwise I would have nothing but bluebonnets out there. In fact next year I will only allow one or two in the front because as you say they form a mat about 3′ across if they get plenty of water. Oh, and I am keeping the bag in the house because last year it was in the potting shed and whilst we were away on vacation the mice/rats got busy opening up every pod and ate all the seeds.

  2. From Pam/Digging:

    I wish I’d known about the nitrogen-fixing abilities of the roots. Just today I pulled out the spent bluebonnets (and pinkbonnets) in the old garden, roots and all.

    I did spend time collecting columbine seed while I was over there. Got a good harvest.

  3. From Cindy, MCOK:

    Shoot, I knew about the nitrogen-fixing properties but I never even considered leaving the spent plants for that purpose. I just pulled up most of mine this week. Next year I’ll whack them off at ground level and let them do their thing!

  4. From Gail:

    You paint a pleasant picture of popping pods! I want to lie in a field and listen to the bluebell seedpods pop…Thanks for the good information on the nigella and larkspur, both are growing in my garden. gail

  5. From Cyd, Spokane:

    Great information on bluebonnets, they look like our lupine. I love your larkspur garden. I let these go to seed every year, the hummingbirds love them.

    Texas bluebonnets are a type of lupine; their botanical name is Lupinus texensis. However, they are are shorter and the flower spikes smaller than the garden lupines of cooler climes. Some visitors have expressed surprise at how small bluebonnets are. I think their impression in the Texas psyche comes from seeing them blanket a field or hillside in solid blue. Alone, they are comparatively insignificant. En masse, breath-taking. — mss

  6. From Carol at Lost Valley Gardens:

    Good information! I did not know about the nitrogen-fixing properties of bluebonnets. Nor did I know that the seed coatings vary in thickness. Thanks for sharing.

  7. From Jan:

    Thanks for the info on saving the bluebonnet seeds. I went and checked and mine are ready to harvest for next year.

    Always Growing

  8. From Mary Beth - Harlingen:

    Sure wish that I had read your post earlier – this morning I pulled all my dyin’ and dryin’ nasturtiums out by the roots . . . When I think of all that wasted nitrogen . . . Great post! I’m putting a link to it in the post I’m writing now.

    I was talking about bluebonnets, a legume, not nasturtiums. — mss

  9. From Dee-SETexas:

    For all of those whom have already pulled your bluebonnet plants out of the ground….decomposers will still return the nitrogen back into the soil or it will be consumed and released back into the atmoshpere to be recycled again. I did not know about that dormant seed adaptation.

  10. From Lucas, Austin, TX:

    Great post. Someone at the Wildflower Center used a term I hadn’t heard before–was it dehiss–to describe the seeds popping out. Ever heard that term? I’m sure I’ve misspelled it…

    What would be your guess as to how far away the seeds can “pop away” from the parent plant?


    I have no idea really. Several feet? Maybe a yard or two? — mss

  11. From Sammy:

    Can anyone tell me where I can get bluebonnet seeds? I’m a new resident of spring texas and have been trying to grow different types of plants. Saw the picture and would love to have some on the patio.

    I’ll send you some bluebonnet seeds but it’s too late to plant them for this spring. You’ll have to plant them in the fall for spring 2011. Email me your mailing address. — mss

  12. From Polly:

    I have the big scraggly mess in my gardens right now. Lots of seed pods but not brown yet. If I cut off the plants will the seed pods dry out OK?

    I’m also glad I read about keeping the roots intact.

    It depends on how close to being brown they are. Think of it as a fetus. It might live on its own if it is only 6 months developed but not if it’s only 2 months developed. Better to just let the seeds ripen and accept “scraggliness” as part of the natural process. –mss

  13. From Katy, Brookshire, TX:

    What is the quickest way to remove bluebonnet seeds from their pods? If I put them in a brown paper bag in the sun, is that the best way to dehisce them? How long will that take? When is the best time to plant the seeds in the Brookshire, TX area?

    Thank you for your help.

    Well I shell my seeds by hand so I can’t tell you how long it will take to put them in a bag and let them pop on their own. I’d guess it depends on how close to being ripe they are when you pick them. I wouldn’t leave them out in the sun though. What if it rains and the bag gets wet and the seeds all go moldy? In Austin, I usually plant my seeds in August a bit before the fall rains. That will probably work for you too. You can get away with planting them as late as Thanksgiving or Christmas but the earlier in the fall you plant them the bigger the plants will be in the spring. Although the most important factor is how much rain they get during their growing season. — mss

  14. From Christina, Watauga Tx:

    My son gathered a large amount or seed pods from our family ranch in Blum, Tx. They are still green. If i leave them in the sun will they mature or do i just need to throw them out and try again next year?

    Depends on how green they are. I wouldn’t throw them out unless they start to go moldy or rot. There’s nothing to lose by keeping them and seeing if they are old enough to ripen off the plant. Experiment. Experiment. Experiment. — mss

  15. From Judie - Georgetown, TX:

    If I just cut from the ground and lay in a new bed (while green) would I have a new bluebonnets next spring at this new spot.

    I have a bed that was absolutely beautiful this year; but I had planted them already blooming from a nursery several years ago and this year they were abundant.

    Georgetown, TX

    Cutting the whole plant and laying them in new beds will work if you let the seed heads turn brown first. Flick your finger against the seed pod and when you hear the seeds rattle inside, they’re ripe. — mss

  16. From Glenda, arkansas:

    I live in Arkansas and last spring in a home improvement store I bought 6 Texas blue bonnet plants. They grew very large and beautiful… I did nothing to them. This year they came back and have taken over my planter bigger and more beautiful than last year. What do I do now? The seed pods are full green and fuzzy so I know not to gather them now but when they are harvested can I dig up the plants and move them to another area? Do I cut them all the way down and plant stuff to grow there? I want them to come back but they have taken over all the other pants and flowers in the planter.

    Bluebonnets are not perennials. After the plants go to seed (and the seeds and plants turn brown) the plants will die. Problem solved. Plant the seeds where you want new plants. — mss