There are many different cover crops for different regions and different needs. Climate, season you plan to plant it, current soil type and most-urgent soil needs will narrow down what is best in an area.
Clover, alfalfa, buckwheat, fall rye, cow peas and vetch are classics. If you Google "cover crops", you can find tables listing what each crop is good at.
Some crops are good for breaking up heavy clay (they can grow in it, and will put down deep roots through it).
Some tolerate infertile soil, drought and heat better than others.
Some produce a lot of organic matter. Others fix nitrogen. Others are good for competing with and suppressing weeds. Others fight erosion well. Something was listed for "water management" but I don't know if that was to resist erosion during monsoon rain, or mitigating droughts.
I guess some combine well with no-till systems. Some grow right UNDER other crops and are called "living mulch", like clover in an orchard.
The easiest way to pick one is to
go to a local feed store and ask what they stock in bulk: that's what works best in your region. Often it will be a mix of plants, where some emerge rapidly and have long, stiff stems for others to cling to and be supported by. In my area, there is usually a lot of Fall Rye in such mixes. Just find out what season each mix is intended for, and "annual vs. perennial".
Probably the best way is to
ask a local coop extension agent or local university Ag department's public outreach department, or local Master Gardeners.
The "Coop Extension Finder " link in my signature block would get you there eventually. I didn't find much right away, so you might have to contact someone below and ask a question. (They might refer you to another website or person.)
The "Texas A&M" link lists every county. If your ZIP code is Henderson County, try this link:
http://henderson.agrilife.org/
The Henderson County Extension Office
[email protected]
Henderson County Master Gardeners:
E-Mail Henderson County Master Gardeners:
[email protected]
Henderson County Master Gardeners, 101 E Tyler, Athens, Texas 75751
903-675-6130
Contact info for actual people to email or call in Henderson County, like Rick Hirsch,
the County Extension Agent:
http://henderson.agrilife.org/...
Be somewhat ready to tell them what you want from it, like
1. "produce lots of biomass fast to amend sandy soil" and "just a catch crop to grow through late fall and winter of one season"
or maybe
2. "something perennial to grow there for a few years".
For background research, try Googling cover crop selection guide, for example:
http://covercrops.cals.cornell...
Table of cover crops with list of what each one does well:
http://www.groworganic.com/med...
http://www.territorialseed.com...
Peaceful Valley "browse cover crop solutions" links :
http://groworganic.com/organic...