One of the reasons bluebonnets fail to bloom is lack of essential bacteria in the soil. These bacteria, known as Rhizobium, form nodules on the roots and are able to fix atmospheric nitrogen. This nitrogen fixation is needed for the bluebonnets to bloom.

If bluebonnets have not previously grown in the area, it is unlikely that they will bloom. In this case, planting a wildflower mix is preferable to planting strictly bluebonnets. (See Section 7,

Selecting Wildflowers by Natural Vegetative Region

.)