Quick answer: 7 native Texas plants have a recorded bloom range that includes December.
7 species
- Buffalograss Bouteloua dactyloides · 9 states
- Carolina jessamine Gelsemium sempervirens · 9 states
- Little bluestem Schizachyrium scoparium · 23 states
- Longleaf pine Pinus palustris · 6 states
- Mexican olive Cordia boissieri · 1 states
- Prairie blazing star Liatris pycnostachya · 16 states
- Witch-hazel Hamamelis virginiana · 28 states