Non-native plants more of a project

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I am on an e-mail list from a major mail order nursery back east. A recent e-mail advertisement from them encouraged me to plant lilies, which of course I could buy from them because it was "A true 'plant it and forget it' gift from nature, hardy Lilies improve with each passing year, becoming more floriferous and sturdy. Their giant, brightly colored blooms are very long-lasting, making perfect cut flowers."

We are different here than most of the rest of the country, where you can plant many things and forget them.

I remember when desert landscapes were first being introduced into Las Vegas and local contractors were just getting their feet wet with this type of landscape design and planting. An elderly woman called me to complain that she bought a landscape of rocks and cactus for $5,000 with no irrigation because it was a desert landscape. Of course, the cacti promptly died the first year.

I have a general rule of thumb I tell our Master Gardeners in classes that I teach -- Anything will grow in Las Vegas, but the more out of place that plant is when planted in our desert climate, the more time, money and energy it will take to make it thrive here. Even desert plants, which originally come from desert climates, need care and attention.

There is some advice floating around in some circles that we don't need to amend our soils when planting new plants. That is hogwash. That research was done in Oklahoma with soils naturally high in amendments. Our soils are extremely low in good amendments and new plants need them, even cactus.

Question: I have bores in my purple plum tree. Have you written an article that could help me know what is the best procedure to save my tree?

Answer: I have talked about removing borers in general from fruit trees, but not specifically from ornamental plums. It is the same procedure. Cut away the wood from where you think the borer is located and follow the sawdust trails just under the bark.

You may actually find the immature boring insect right now in the tree just preparing to exit. If you find it then, you must kill it and clean out the wounds in the tree. Do not cover the wound with anything. Let it heal on its own.

Plums are notorious for getting sap oozing from limbs and a trunk that shows signs of borer problems when there aren't any. If you cut into the area with a knife and don't see the sawdust trails or sawdust encrusted with sap, then don't go any further. Plums are sappy trees.

Q: I have several varieties of citrus plants that were planted as young trees last September. They suffered a little during the winter and lost many of the leaves. The trees were wrapped with burlap on the very cold nights. The Meyer lemon has now blossomed and seems to be doing OK. However, there are very few remaining leaves and only a couple of signs of new leaves coming in. The tree trunk and branches look good, and the trees are all irrigated. I gave all the trees Fertilome Citrus Food in early March. I did not prune any of the trees. Is there anything I should do for the trees at this time, particularly the Meyer lemon?

A: At the Master Gardeners Orchard, due to late freezes this year, we lost flower and leaf buds to the cold. This has left bare branches on some trees because the leaf buds were killed. New buds will be produced by the tree, but it will take some time before the plant can create some new ones -- a few weeks perhaps.

On the citrus, the cold probably did some damage to the more susceptible citrus. Meyer lemon is one of the most cold-tolerant citrus trees, so damage was most likely less.

Other citrus, such as navel oranges, limes and the like, could be damaged severely depending on the temperatures you had and at what stage of spring deacclimation, or stage of waking up from their dormancy, the temperatures happened.

After mid-winter and spring approaches, plants become more susceptible to damaging temperatures than in the dead of winter. Much of it also has to do with exposure to the wind, which can be very damaging and make the freezing temperatures even worse.

All you can do is wait and see what happens and treat them as if they were still alive and growing. Most citrus are grafted onto a rootstock, so if growth occurs near the ground, it is probably not salvageable. Burlap wrap may help in protecting from winds, but it won't help much with freezing temperatures.

Q: I have an all-in-one almond and the tree appears to be doing quite well. I have about two dozen almonds growing. I noticed that something is eating the fruit. They are digging a small hole into the fruit and eating the inside. I have also noticed small holes in some of the leaves. I have just wrapped the tree in bird netting. Do birds eat almonds?

A: Birds do eat almonds, but they usually remove the entire nut or remove the flower bud or developing nut. This sounds more like one of the larvae that attack almonds early on, perhaps one of the leafrollers, which are small moths whose larvae attack developing nuts.

These can be problems in California almond orchards, but I have not yet seen them here. Growers usually apply a cover spray right after bloom if these insects are a problem. They usually do not create big problems, but if this is something that persists, you can apply an insecticide just after bloom is finished and the nut is developing.

Organic pesticides that may be labeled for their control have ingredients that are called spinosad or Bt. The Bt may be called Dipel or Thuricide on the label.

Q: I bought a citrus food to apply to my lemon tree. The problem is that almost 75 percent of the leaves fell off -- only fruits and flowers are left. Is my tree dead already? Please give me any suggestions or ideas what to do.

A: It is hard to know what shape your citrus tree is in now. If a fertilizer is applied too close to the trunk of the tree, it can kill the tree. The fertilizer is a salt and it's just like putting salt too close to the trunk of any plant.

The fertilizer should be placed a distance from the trunk and watered in thoroughly to move it into the root area. But the water should not wash the fertilizer so that it is in direct contact with the trunk. The fertilizer should not be applied to an irrigation well around the tree in large quantities. Again, the salts in the water can damage or kill the tree if the water comes into contact with the trunk.

All you can do at this point is wait it out and see if it produces new leaves. Sometimes, if you are lucky, you can just get enough salt to knock the leaves off without killing the tree.

What I would recommend is flushing the area where the fertilizer was applied with lots of water and try to wash the fertilizer salts out of the root zone.

The worst thing you could do now is to let the soil go dry around the tree and let the salts reconcentrate again. Flush it with a foot or more of water several times over the next few days and then return to a normal watering pattern.

You might want to consider fertilizer stakes next time. They are much safer to use and convenient.

Bob Morris is a horticulture specialist with the University of Nevada Cooperative Extension.