The state flower of Texas, the Texas bluebonnet is a petite annual wildflower that beckons thousands of people to the countryside to view its springtime flower show. Enjoy its sky-blue beauty in your landscape by planting it in dry, rocky sites, such as along driveways and curbsides. The plant reseeds vigorously so you can count on Texas bluebonnet to provide color year after year.
Texas Bluebonnet Overview
Where to Plant Texas Bluebonnet
When selecting a spot to plant Texas bluebonnet, look for two things: a location in full sun most of the day, and fast-draining, alkaline soil. Although this plant is native to Texas, it can be grown in other areas and as low as in zone 4.
Good places to plant Texas bluebonnet are rocky hillsides, along driveways and curbsides, in meadows, and raised flower beds. It can even be planted in large containers. Whether you plant a drift of Texas bluebonnets or combine them with other wildflowers, their bloom is spectacular.
How and When to Plant Texas Bluebonnet
Plant transplants in early spring and look forward to plants blooming in April or early May. If starting from seed, broadcast the treated seeds (more about that under How to Propagate Texas Bluebonnet) between August and mid-November depending on your zone. The cooler your climate, the earlier you need to plant the seeds to give them time to germinate and develop a root system before the cold sets in. Broadcast about 8 to 10 seeds per square foot and gently rake them in. Soil contact is important; however, the seeds should not be covered with more than 1/8 inch soil. Water the area lightly after sowing and keep it damp. At temperatures between 55 and 70 degrees, the seeds will germinate in 7 to 30 days.
Texas Bluebonnet Care Tips
Light
The plants require at least 8 to 10 hours of full direct sun to bloom. South- or west-facing exposures are ideal.
Soil and Water
Texas bluebonnets need soil that is dry and drains fast and well, with a pH of around 7.5. Light, gravelly soil is ideal. Bluebonnets cannot tolerate poorly drained, clay-based soils.
The plants do not require watering other than to aid seed germination. Do not water the bluebonnet plantings in spring or summer; excessive moisture will spur seeds to sprout, and the resulting plant will not be able to survive the heat of summer.
Temperature and Humidity
Texas bluebonnets are winter-hardy annuals that can be grown even in northern climates. They continue to grow in mild winter weather if they had the chance to establish their root system before the fall. The plants can even survive a hard freeze.
In humid climates, the plants, especially seedlings, might be affected by fungal disease.
Fertilizer
Fertilizing Texas bluebonnets is not recommended. Too much nitrogen will lead to foliage but few blooms and in fact, as a member of the legume family, Texas bluebonnets fix nitrogen in the soil, just like beans and peas.
Pruning
Do not deadhead the spent flowers but let them go into seed. If you have Texas bluebonnets planted in a larger area, you can mow them to a height of 4 to 6 inches after their seed heads have formed and the foliage has turned brown. Mowing not only helps to cut down on weeds and other grasses that may compete with the bluebonnets but also helps disperse the seeds.
Potting and Repotting Texas Bluebonnet
Texas bluebonnets can be grown in a 3- to 5-gallon containers with large drainage holes. Fill the container with well-draining potting soil and plant either young transplants or plants in it, spacing them 10 inches apart. While Texas bluebonnets in the ground don’t need extra watering, container plants need to be watered regularly.
Because Texas bluebonnets are annuals that won’t outgrow the container during their life cycle, repotting won’t be necessary.
Pests and Problems
As a native plant, Texas bluebonnet is blissfully pest-free, with one exception. The pill bug is an insect that goes after the seeds, cracking them open and feeding on the inside.
The other major problem is poorly drained soil, in which seeds might germinate but the plants will never fully develop.
How to Propagate Texas Bluebonnet
Texas bluebonnet is propagated from seeds. Note that the seeds of bluebonnets have a very hard seed coat that causes a very low germination rate (as low as 20 percent). If you leave it up to nature to wear down the seed coat, it can take up to two years for the seeds to germinate. That’s why it is important to use only pretreated scarified seeds whose seed coat has been nicked, or nick the seeds yourself with a knife or sandpaper.
If using untreated seeds, make sure to start with a generous number of seeds as only a fraction will make it.
Water the seeds well after planting and water seedlings a couple of times in fall to encourage strong growth. Expect Texas bluebonnets started from seed to bloom in late March or early April, depending on spring weather conditions.
Types of Texas Bluebonnet
There are a few varieties of Texas bluebonnet but Lupinus texensis is the easiest to find and, thus, the most popular. If you're looking for something out of the ordinary, here are others to look out for.
Lupinus havardii
A larger bluebonnet with flower spikes up to three feet tall, Lupinus havardii is challenging to cultivate beyond its natural habitat.
Lupinus concinnus
The smallest bluebonnet, Lupinus concinnus reaches only 2-7 inches tall. It flowers in a unique blend of white, purple, and lavender.
Lupinus plattensis
This is the only perennial species and is found in the sandy dunes of the Texas Panhandle. Also known as the dune bluebonnet or the plains bluebonnet, it blooms in mid to late spring and tops out at about two feet tall.
Texas Bluebonnet Companion Plants
Pair bluebonnet with other dryland natives. It is easier to avoid overwatering a Texas bluebonnet planting when you partner them with other low-water plants.
Yucca
These evergreens grow in pretty much the same conditions as Texas bluebonnets: abundant sun and dry and well-draining soil.
Indian Paintbrush
This is a native plant that also does well in prairie pockets alongside other native plants like Texas bluebonnets.
Prickly Pear Cactus
The prickly pear cactus shares the same growing conditions as Texas bluebonnet, including hardiness down to zone 4.
Frequently Asked Questions
- How long to bluebonnets stay alive?
- Do Texas bluebonnets only grow in Texas?