Growing a Bluebonnet from Seeds
Growing Bluebonnet seeds no longer has to be an exercise in frustration. The bluebonnet has a powerful defense mechanism to ensure its long-term survival. By encasing its seeds with a durable outer coat, the plant prevents germination of all seeds in a single growing season. This means that a poor growing season will not destroy the plant’s chances to grow again under better circumstances. This limited germination has also meant that the efforts of many gardeners were met with poor results. Fortunately for frustrated gardeners, study and experimentation have paid off, and means to successful Bluebonnet seed propagation are at hand!
Bluebonnet Seed Treatment
Treatment of Bluebonnet seeds involves scarification. This process mimics the effects of time and weather, wearing down the seed coat and allowing moisture to penetrate. Commercially prepared seeds are now readily available. Once the seeds have been scarified, they have a limited shelf life. They should be planted immediately, and will germinate within ten days.
Ambitious gardeners may prefer to gather and prepare their own seeds. The seeds resemble pea gravel, often colored in shades of blue and tan. The hard outer coat can be scratched up with sandpaper, or lightly cut with a knife. Some growers freeze the seed, and then pour boiling water over them to rupture the coat. Still others mimic the commercial process using sulfuric acid to scarify, then water to rinse the seed. This method, while effective, requires caution and skill as well as safety equipment. It is best left to the experts.
Bluebonnets naturally add nitrogen to the soil. In soil lacking nitrogen, Bluebonnet seeds may have difficulty in getting started. This is easily overcome by dusting the lightly moistened seeds with powdered Rhizobium. This a bacterium that allows and encourages nitrogen fixation, the conversion of nitrogen in the atmosphere into a form useable by plants.
Planting Bluebonnet Seed
The time for planting Bluebonnet seed is early September to mid November at the latest. The growing plant needs time to develop a substantial root system before it will be able to flower. The cold winter months provide the time needed for this. Choose a location with 8 to 10 hours of direct daily sunlight. Bluebonnets are drought hardy. The soil must drain well, and watering should be kept to a minimum. Plant or “rake in” about 8 to 10 seeds per square foot at a depth of one-eighth inch. The seeds must be covered in order to germinate. Lightly water the seeds after sowing. Moist soil will aid the growth of the seeds, but over-watering will kill them. Erring to the side of drier conditions is best.
Once the seeds have successfully germinated, the hardest work for the gardener is past. Only occasional watering is needed. Feeding and fertilizing are generally unnecessary. Watch for attacks by pill bugs. These roly-poly menaces can devour plants at an alarming rate. The young plants will be ground hugging, and will grow to the diameter of a dinner plate. Frost may turn the leaves red, but is unlikely to kill the plant.
Bluebonnets bloom between March and May. Pinching of the spent flowers will prolong the bloom. When the blossoms are done, the dead and drying plant may linger for sometime before releasing fresh seed. Left in place, the Bluebonnets will release seed ensuring the next year’s growth. Some gardeners prefer to remove the unsightly spent plants without waiting for the seed. For them it is preferable to simply purchase prepared seed and begin anew.