Coffee grounds are an excellent soil additive and readily available -- folks drink a lot of coffee!
The grounds are high in nitrogen, hold moisture, and are slightly acidic -- perfect for New Mexico's typically alkaline soils. And earthworms thrive on coffee grounds -- spread the grounds over a patch of earth and the earthworms will reward you with loose, enriched soil. (And no, the worms don't crawl faster on a coffee diet; grounds have only a smidgen of caffeine left in them.)
Coffee grounds may be used for top dressing or side dressing of plants, spread thickly as a mulch, or mixed with soil. Tests have shown that most plants do quite well in a 50/50 soil/coffee mix, so it would be difficult to add too much. The only considerations are: 1) a thick layer of coffee atop the soil may form a crust and prevent water from penetrating, and 2) grounds should be used less heavily around fruiting plants like tomatoes, as the high nitrogen content may result in lots of dark green foliage but fewer fruit.
Compost "cooks" much more quickly if you add coffee grounds to it, the nitrogen fueling the microorganisms that do the work.
Besides what you produce at home, most coffeehouses will give you their coffee grounds if you ask them -- it is, after all, the heaviest part of their trash stream and you are hauling it away for them. Most companies use biodegradable coffee filters, and these can go right into the soil or the compost pile.
Coffee grounds -- some of the best, free fertilizer around!
Straw is often used as a mulch. Straw bales have many uses in the garden, particularly in New Mexico.
Straw bales make good wind breaks, protecting delicate bedding plants and young sprouts from the drying New Mexico wind. Some small-scale farmers in New Mexico routinely alternate rows of bales with rows of crops.
A "U" of bales covered with plastic makes an excellent cold frame -- just wrap the plastic down over the sides and anchor it with soil or boards. The bales provide insulation while retaining moisture, and the light-colored straw reflects sunlight onto the crops. The bedded plants can be moved out to new locations, or the "baleframe" can be constructed in place and removed once the seedlings are big enough. Rows can also be covered in this way, the parallel bales removed once the crops are "hardened".
Straw bales can be used to easily make raised beds -- just arrange the bales in a rectangle and fill with rich earth. The bales help retain moisture (raised beds tend to dry out more quickly) and make a pleasant surface for kneeling or sitting upon while gardening. Bales used this way can last several seasons, then be taken apart and used for mulch. Such a bed can also be covered in plastic to encourage early warming of soil and sprouting, the plastic removed once the season warms up.
If you have the room, straw bales can also be used to make a compost bin.
Straw bales are also just fun to have around! Sit on them around the barbecue, lie on them while stargazing, build a fort... The bales find many uses on their way to being mulch.