What kind of texture?
What type of texture are you applying?
How thick will it be?
Have you heated the job with any oil belching temporary heaters?
Are you spraying or rolling a texture?
If you are using drywall compound from a box or bucket, the premixed kind, you would be well served to add 20% by volumn primer to the mix. This does not serve as a complete primer substitute. It can, if your budget is tight.
A mixture of this 1/5 ratio prevents a condition known in the trade as "crazy cracking" from occuring in your beautiful, rich texture.
An amount of primer as small as 1/2 gal per 5 gal of premix will often be sufficient to prevent the tendency to become openly porous and crack as it shrinks and dries. This amount makes the texture infinitely more sprayable, and also is very helpful in making a hand troweled finish more predictable and therefore manageable. Also helps set up times in thicker applications.
Sand and other texturing substances can also be added, in addition to the primer. This makes any DW texture impossible to differentiate from plaster when repairing, blending, or new construction.
Been doing it full, part, or retired time for 34 yrs. Has not failed me yet---except before I learned to add the primer! Regular topcoat paint works in a pinch, just not quite as well and predictably.
SgtSR