We're planning a roadtrip to Texas in April. We have about 3 weeks and we plan to do (roughly) Dallas-Palo Duro-Monahans-Marfa-Big Bend NP-Fort Stockton-Hill County-San Antonio-Austin-Houston-Galveston-Dallas. We chose April as we wanted to get to see all the wildflowers in Hill County, but we're now considering travelling in September as it would be more convenient for us because of work.
Which month would you say is better for that trip? Is 3 weeks enough for what we're planning to do?
Thank you in advance for your help.