Roses need plenty of TLC to retain their good looks

: My roses are not looking good. We have had them for many years and we water and fertilize them regularly. Some friends told us they were just suffering from the heat. The leaves are drying up and there are dark marks along the stems. I am sending some pictures of my plants. Please help.

A: The pictures gave it away. This is rose canker. It is a fungal disease and weak pathogen, usually attacking roses that are in poor health or damaged. It is usually spread by splashing rain or overhead irrigation like from a hose or sprayer attached to a hose.

Prune out infected stems with clean and sterilized pruning shears. Fertilize the plant adequately and at the right times of the year. In other words, take better care of the plants.

This disease can spread between canes that damage each other by crossing and rubbing, thus opening wounds; are improperly pruned; if you are using unclean shears; or are pruning infected canes and then pruning uninfected ones. Usually the plant can fight it off, but if it is in poor health or not properly fertilized and cared for, it cannot.

Q: I have a Bartlett pear tree and the some of the fruit has lines and blotches that resemble rust in the skin. I don't know what is causing this. It appears to be getting worse each year. The only spraying I do is with a borer spray on the trunks in the spring and fall. Could you enlighten me as to what I am doing wrong or not doing that I should? The fruit has an excellent flavor and the rusty-looking area doesn't seem to go beneath the skin.

A. Pears skins don't like this climate as much as they like cooler and less extreme parts of the country. Pears in our climate often are pretty ugly looking but they taste good. The fruit gets bumpy, scarred and develops a lot of what you are talking about.

In my opinion, these pears have a lot more character than those Bartletts from producers in Washington that all look the same. Much of it has to do with our winds, blowing dirt and low humidity. We don't have to spray for pests like they do, so we can grow pears here pretty much organically.

Certainly, the pears will look a lot better if they can be protected from the winds -- if looks are important to you.

Also, I really wonder if you need the borer spray at all. You will do better just keeping the trees healthy and painting the trunks and lower limbs with diluted white latex paint for borer control and protection from sunburn. I actually think you are wasting your money with the sprays.

Q: At work several of us have live potted plants at our desks. These tiny black "gnats" or something pester our faces. We have taken our plants home more than a week ago, but the gnats are still around. We fear they laid eggs in the vents. So, my plants are now home and these gnats are invading the air at my home. What do I do? I am afraid they will multiply in my potted plants. Is the soil where they originate?

A: If these are fungus gnats, then they are living off of the decaying matter in any soil that is kept wet. I would recommend a product that you can order online. I have never seen it available in town. It is called Knockout Gnats and is available from Gardens Alive. This is an organic pest-control product and has very low toxicity to humans.

You must treat all of the plants in your living area or the gnats will move from one plant soil to the next. They are not in your vents unless you have some potted plants up there.

Q: My pomegranates have these nasty looking bugs crawling all over them. If there is a crack in the fruit, they are crawling in and out of it. They are kind of yellow-bodied spider-looking things. Also, our tree had a bumper crop last year and this year, it seems only to have fruit on the outside limbs. We didn't cut it back and is more treelike than bushlike.

What should we feed it and when? When is the best time to pull the fruit? We don't use pesticides on our trees, but is there a natural cure for the bugs?

A: From your description, I am not sure what is crawling on your fruit. However, if it has a crack in the outside, any pest will get inside.

Try to check daily for splits in the fruit and remove those that have split. They will not ripen all at once so you will probably only see a few ready for harvest each day.

You will fertilize pomegranates the same time as other fruit trees: in January. Use a fruit-tree fertilizer, a good lawn fertilizer like a 21-7-14 or lots of compost.

Without identifying the bugs and determining whether they are really causing problems, I hate to recommend anything. You need to get that critter a name and then I can help you. Bring it into our master gardener help desk and it will get identified or at least the gardeners will determine if it wears a white or black hat. Call the desk at 257-5555 and you'll received directions for where to bring the potential varmint.

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 extremehort@aol.com.