Hi, Dave,

Thank you writing to ask about putting in a buffalograss lawn. It's a low-maintenance grass once established; growing it from seed can be labor intensive and, according to CSU Extension Fact Sheet 7.224 (Buffalograss lawns), a somewhat frustrating process. Once it's established, though, it can survive without irrigation (if non-irrigated, it will become dormant during most summers and is prone to weed invasion while dormant). I'll give you the link to the fact sheet, but to answer your question about when to sow:

Buffalograss seed can be planted anytime in the spring until late July. Seed planted too late in the season (between August 1 and October 1) may germinate, but the young seedlings are quite susceptible to being killed during the winter. Seeding during October-December (dormant seeding) will not germinate until the following spring with warming soil temperatures; the dormant seed will not rot or otherwise degrade over the winter.

https://extension.colostate.edu/topic-areas/yard-garden/buffalograss-lawns-7-224/

Mulching is an option to keep soil from blowing away and protecting your seeds. Straw is the traditional material used for mulching, but processed wood fiber and other types of mulches are available. Processed materials contain no weed or grain seed and are easier to spread, but more expensive. If you use straw, use clean wheat, oat or barley straw. Avoid rye straw. Below is another link for information about mulching. This one is from Michigan State University Extension -- go to Step 11 (Mulching) for information about what to use and how 

https://www.canr.msu.edu/resources/establishing_a_new_lawn_using_seed_e2910

If you have any other questions about your lawn and home garden, please don't hesitate to contact us again.

Regards,

Patty, CMG Boulder County