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Larry Sagers
Aphids attack many flowers, and the best control is to let predators and parasites control them.

Sometimes being a garden writer gets a little personal. Like all of you, I planted my flower beds in good faith several weeks ago and have waited patiently for them to flourish.

The weather kept the warm-season flowers from flourishing, but then conditions changed rapidly. With the heat, the warm-season flowers are now growing well, but several other problems are plaguing my posies.

In a perfect world, there would be nothing to bother my prized blossoms. Insects would confine their voracious feeding to weeds that dare make an appearance, thereby saving me countless hours of weeding. Diseases would attack any pests that might want to eat my fragrant flowers.

Unfortunately, insects and diseases show no respect. They are happily munching away on my tender blossoms. I don't mind them snacking occasionally, but they seem to think I have set out a banquet for them, their friends and their relatives.

While there are many pesticides to control these pests, other options are often more effective and less expensive.

At the top of the pest list are the slugs and the snails. If young seedlings disappear or your plants develop large holes in the leaves, these mollusks are the likely culprit.

They are particularly fond of hostas but eat many other flowers. They love cool, moist environments, so the wet spring was good for them. Unfortunately, they are able to tolerate almost any condition, as long as they can find some moisture under the plants.

They are not easy to control. Start by going on patrol. After dark or early in the morning, go out and pick them up.

Although the temptation is to smash them into oblivion, keep in mind that they are not "he's" and "she's" but "its," so all have eggs that will eventually hatch — even after you crush the pests.

Throw them into a bucket of soapy water, tie them into a plastic bag and send them off with the trash.

Baits are effective but often misused. Most become ineffective once they get wet, so consider using traps or stations to extend the baits' effectiveness and prevent birds and pests from consuming the baits.

Another persistent and aggravating problem this year is the European earwig. I suspect the spring moisture increased their numbers, too. European earwigs are sneaking out at night and skeletonizing the leaves on my verbena, castor beans and several other flowers. Go out with a flashlight and see if they are striping the leaves off of your prize flowers, too.

Like the snails and slugs, they like to hide. They are not social insects, but they do cluster in large groups under rocks, boards or other moist, dark places. Finding and destroying these nesting areas will help reduce their numbers. They are particularly fond of marigolds, dahlias, zinnias and hollyhocks.

The pests are supposed to feed on decaying organic matter, but they feed on almost anything. They are predaceous, meaning they feed on some other insects, but their damage to seedlings, flowers, fruits and vegetables is much more destructive than any benefits they provide.

There are earwig baits, but sometimes homemade traps are equally effective. There are several ways to trap earwigs, including:

• Place a half-inch of vegetable oil in a shallow tin can and place them in the garden.

• Poke a pencil-size hole in the bottom of a cardboard box baited with oatmeal or bran.

• Roll up an old newspaper (or an old piece of hose) and place the tubes near the plants at sunset. Empty them into a bucket the next morning.

Bands of sticky adhesive applied around the stems of large flowers can help prevent earwigs from attacking the leaves and flowers.

Tobacco bud worm is another pest that might cause serious damage before you notice it. It is fairly specific, attacking nicotiana or flowering tobacco, petunias, snapdragons and geraniums. At first, the plants just stop blooming because the insect larvae eat the inside of the blossoms. They then start to chew holes in the leaves.

If you have sharp eyes, you can hand pick the larvae and destroy them. Otherwise, to control the pests, apply BT sold as dipel or thuricide, when the problem starts. Waiting until the damage is severe usually requires you try something stronger.

Aphids are numerous and attack many flowers. Usually the best control is not to spray but let predators and parasites control them. If you can't wait for that to happen, simply spray them off with the garden hose.

Spider mites show up when the weather gets hot and dry. Treat them the same way as the aphids. Sometimes you will see webs associated with the mite infestations. Use the hose to beak up the web and remove the mites.

Unfortunately, these are not the only pests that might be attacking your flowers. Next week we will cover some of the flower diseases that are causing problems this season.


Larry A. Sagers is the horticulture specialist, Utah State University Extension at Thanksgiving Point.