Mulch is one of the main components of desert gardening. Read about the many types of mulch you can buy (or scrounge)and how they benefit your desert garden.
Mulching is an integral part of desert gardening. It covers the soil. It reduces evaporation caused by sun and wind exposure. It helps ameliorate temperature extremes, and it prevents erosion.
Additionally, mulch stifles (or at least limits) the growth of weeds, thereby reducing competition for water and nutrients.
There is an almost endless variety of mulch...limited only by our imagination and a few basic principles. You can buy mulch from your local nursery. Or you can scavenge. Here is a small list of materials that can be used as mulch:
- Straw (A great mulch, although it can be scattered ruthlessly by high wind)
- Leaves (shred them first)
- Hulls: rice, buckwheat, peanuts, cottonseed, oats, or shells from nuts.
- Grass clippings (in a dry, desert garden, the grass will probably not rot, but instead turn to straw as they dry. Since they won't decompose, they won't rob nitrogen from the soil.)
- Shredded bark (cedar, cypress, pine)
- Sawdust
- Shredded sugar cane (called bagasse)
- Shredded paper (make sure it isn't coated, and can absorb water. I use paper from my paper shredder for mulch.)
- Newspaper (again, don't use the glossy magazine sections or advertising inserts. Simply use the black and white sections.)
- Peat moss (it sometimes cakes)
- Gravel
Some people think that impermeable ground covers can be used in place of mulch. The problem with these (usually plastic) materials is that while they do suppress weeds, and retain water, new water and nutrients cannot get through them into the soil. Use them instead when creating dry streambeds to direct harvested water, or close to the house where termiticides had been applied.
Permeable weed barriers are acceptable, because they are made of material that will let in water, air and nutrients. One problem with these "cloth" barriers is the pores tend to clog up with dust in desert environments.
If you have a hillside you want to mulch, I would caution against using bark mulch or any other type of lighter mulch. The reason is that bark, straw, bagasse and others will probably wash away in the first gully gusher you have.
I have found that gravel works best on hillsides. It helps retain moisture, and provides foundations for small plants to get footholds. Since the seeds of many indigenous desert plants can live over a century in the ground before germinating, I gravel-mulched an entire area of apparently barren desert area. In two years, plants started sprouting. Granted, in that area, I didn't have much of a choice as to which plants germinated. I was however pleasantly surprised when a variety of desert and Plains grasses and flowers emerged. One problem with gravel mulch is that it can become very hot. I wouldn't use gravel mulch near the house in a desert environment, and, in most cases, I'd plant some ground cover over it to help reduce the heat until more plants become established.
