In right location, bamboo will grow in desert landscapes

: I was told by a bamboo supplier that there is a type of bamboo that can be successfully cultivated in the desert southwest. Unfortunately, I have lost the information he gave me. I understand that any plant requires more water while it is being established, but I'm wondering if planting bamboo is possible in this climate and would maintaining bamboo require too much water to have any xeriscape potential?

A: One of the safest bamboos for you to try is golden bamboo, which can grow quite tall -- more than 10 feet -- with 1-inch diameter culms or stems. It should be noted that it is what we call a running bamboo, or in other words it can spread.

Some bamboos are clumping types and they do not spread very far. The running type of bamboos can be invasive if you are not careful.

Another choice is a bamboo called Alphonse Karr; it is a clumping type. Unlike golden bamboo it is a bit harder to find, but you may locate it on the Internet. It is not as cold tolerant but should do well here in protected areas.

A very tall bamboo that may do well in some locations is Weaver's bamboo, which can be used, as the name suggests, for weaving and is also edible. This is a clumping bamboo, but it could sustain some damage during cold winters.

There are a few other varieties as well.

All bamboos have a high water requirement but they could still fit into a xeriscape or mini oasis type landscape. Plant the bamboo in an area designed for high-water use, usually closer to the home where people congregate.

Q: I grow lettuce, radishes, strawberries and cucumbers. The radishes do not seem to develop bottoms as they should.

A: Radishes will fail to develop good bottoms, as you say, if they are planted too close together, planted too early or fertilized too heavily.

Sow radish seeds in about early to mid-February and make sure you thin them so they are about 3 inches apart. Use compost as a fertilizer source and avoid heavy applications of nitrogen fertilizer.

Q: What annuals or small perennials might you recommend for containers that get full Las Vegas summer sun?

A: This is one of those questions I do not like to answer because tastes in plants vary so much. I can make five or six recommendations and you may not like any of them. It is easier if you do your homework and find five or six plants that you like and then ask how they will do.

How they will do depends on the size of the container in most cases. The smaller the container, the hotter the soil will be. Plants that are not desert plants will suffer greatly in small containers.

Doubling potting containers -- so that one container sits inside of a second container -- will help a lot. And if the container is large enough, you can plant just about anything.

Q: Would it be OK to spray down my Carolina cherry trees at night being it has been so hot?

A: I think you are referring to the Carolina cherry laurel. There was a phase of using them in landscapes here about 10 years ago. I see more of them appearing lately.

They do not do well in the heat here, particularly in rock landscapes. They just fry. A lot of them have been planted, but you don't see any old ones. That will tell you something. It is not been because they have not been tried.

You could spray the leaves down but I don't think it would do them much good and I don't think you would accomplish anything. The cooling effect in this climate lasts about 10 minutes.

Q: I have a mulch pile going for the first time. It is decomposing nicely, but is filled with all kinds of bugs. I don't want to put the bugs on my plants with the mulch. How do I get rid of them before I apply it?

A: Just to set the record straight, I would like to explain the difference between mulch and compost. Compost is something different from mulch.

Mulch is applied to the top of soil and used to control weeds, conserve water, keep the soil cooler, and, in the case of organic mulches, help enrich the soil as it breaks down on the surface.

Mulches can be chipped wood products (organic), rock (inorganic), plastic sheeting (inorganic), newspaper (organic) or anything else laid on the surface of the soil. Once the mulch is mixed into the soil or begins to break down, it is no longer considered mulch. It is then said to be composting.

Compost, on the other hand, is organic material added to the soil that breaks down and adds nutrients and tilth. Composting relies on a carbon source such as wood chips, grass clippings, plant-material kitchen scraps and newspaper, and its decomposition in the presence of moisture, a source of nitrogen and lots of air.

If your compost pile is decomposing correctly, the heat it creates is sufficient to kill nearly all insects and most plant diseases. If this pile is not decomposing correctly, then the heat will not be enough to kill insects and diseases.

To get your mulch pile to decompose, you will need to keep it moist and turned frequently so that air can penetrate throughout the pile. You also should add a source of nitrogen to help generate sufficient heat. This can be a commercial fertilizer high in nitrogen or fresh manure.

The speed at which this pile will decompose will depend upon the balance between the carbon sources, nitrogen, air and water. Making sure the carbon sources have been chopped or finely divided and turning the pile frequently while keeping it moist will speed up the decomposition and generate enough heat to kill insects.

If you do not manage this pile correctly, you will have to contend with bugs and other vermin. One method of killing the bugs in your particular pile is to cover it with clear plastic and seal the edges so that heat will build under the plastic. Unfortunately, when you do this, you also will kill most of the good organisms that are helping decompose your mulch pile. In other words, your pile will be sterilized.

Bob Morris is an associate professor with the University of Nevada Cooperative Extension. Direct gardening questions to the master gardener hot line at 257-5555 or contact Morris by e-mail at morrisr@unce.unr.edu.