Zanthan Gardens
Weblog of a Central Austin Garden

If you’ve ever bought bluebonnet seeds, you might have noticed that they looked like varied multi-colored pebbles. But if you collect your own seeds, you might notice that all the seeds from the same plant look alike.

When the bluebonnets are blooming in my yard, I go around marking plants from which I want to save seeds. I’m a bit of an extremist so I tend to mark plants with the deepest blue flowers and the palest blue flowers. Every once in awhile a pale pink bluebonnet or white bluebonnet will appear but these rarely set many seeds. I saved seeds from the child of my oversummering, December-blooming bluebonnet and notice how pale beige they are compared with the others.

I saved these seeds not because the plants were remarkable but because the seeds themselves were so pretty.

The week before we went on vacation seven of inches of rain fell and immediately the bluebonnets began sprouting. The week we were gone, we received an additional 3.5 inches. I returned to find my yard covered in bluebonnet sprouts of the seeds I didn’t save. I’m going to have to hustle to get my saved seeds in the ground somewhere.

I worry that 2008 might not be a very good for Texas’s beloved state flower, the bluebonnet. Under ideal conditions, bluebonnets sprout in late September or early October after fall rains break summer’s hold. By Christmas, each plant has formed a flat rosette about the size of a salad plate. The root system gets firmly established as the rosette grows to dinnner plate size. By late February, the bluebonnet sends up multiple stalks forming a compact little bush with a flower at the end of each stalk. If you pick these first flowers, the bluebonnet will stay bushy and more flowers will form on side shoots.

However 2007 was an odd year weather-wise. Austin enjoyed a cool, wet summer and endured a hot, dry fall. In my yard quite a few bluebonnets sprouted from fresh seed in June. Although this happens every year, these early summer seedlings rarely survive the heat and droughts typical of August in Austin. In 2007, seventeen plants ended up successfully oversummering and are already forming little bushes. On December 15th one of these flowered.

2007-12-22. The bluebonnets which grew over the summer are now forming small bushes ahead of schedule.

Unfortunately very few bluebonnets began sprouting in the fall of 2007. Only in the last couple of weeks of the year did I begin seeing new seedlings. Of course, they are quite small for this time of year, only a a few true leaves rather than a large rosette. And the weather remains very, very dry which means that they are not getting off to a good start.

2007-12-22. This bluebonnet just sprouted; it is a couple of months behind.

2007-12-22. This time of year, the bluebonnets plants are usually form rosettes about 6 inches across.

While the gardener may fret, the bluebonnets are employing their long-term strategy for survival. Their seeds have a tough coat which makes them difficult to sprout when dry. The coats are of various thicknesses so that only some of the seeds sprout in the same conditions and other remain in reserve until their coats are worn down. Even though the plants are fewer and smaller, once conditions are right, they will still manage to send up a flower or two. The seeds that didn’t sprout this year are waiting to sprout next year.

Now I’m waiting to see what the other oversummering bluebonnets will do. Will they also flower early? Will they be more subject to freeze damage in January and February? Or will the plants just sprouting now catch up to the plants which have been growing last June so that they all bloom at once?

Several people have asked me how to propagate bluebonnets…how to tell if the seeds are ready. It’s easy. Don’t cut back the bluebonnets or mow until the seed cases are brown and you can hear the seeds ratttling inside. If you tap the seed case and it pops open, you know they’re ready.

To release their seeds, bluebonnets pop open with a little twist.

You can let the seeds reseed on their own (a bunch will anyway, as long as you don’t mow). With this method, some will be lost to birds, fire ants, and hot weather. Or you can collect the seeds, store them in a cool dry place, and sow them where you want them in August before the fall rains. If we have a rainy early summer, some bluebonnets will sprout now but, unless you baby them through the long, hot summer, they probably won’t survive until fall.

Bluebonnets naturally sprout in the fall, grow all winter, and flower the following spring.

You’ll find all sorts of advice for nicking the hard seed coats or rubbing them with sandpaper. This might be necessary with old dry seeds that you buy. I never do it because my own seed is fresh. Sometimes I soak them overnight or until they plump up. I did this the first couple of years to get started but now I have more sprouts than I can deal with an so I don’t need to go to any extra trouble. I let them sprout and transplant them where I want them.

Bluebonnets have hard coats so that they don’t sprout all at once if it rains. In Texas, it might rain and some sprout, and then die off in a long dry spell. But since they don’t all sprout at the same time, some are kept in reserve until more favorable conditions present themselves.