Q. The petunias we planted a month or two ago looked great until recently. Now the flowers are opening with holes chewed in them. How can I stop this damage?
A. I start getting questions about this problem every year as summer settles in. Your plants are the victim of the geranium (tobacco) budworm. This tiny green worm hatches from an egg laid on the flower bud by an inconspicuous gray moth. After hatching, the worm feeds on the flower bud and leaves, and when the flowers open they have holes in the blossoms. If you look carefully, you may even spot the worm itself. With severe infestations, flowering may virtually stop. Geraniums and roses are other hosts for this pest, and control methods are the same for all.
To remedy the situation, you will have to control the budworm. Sevin (carbaryl) is an effective pesticide for use on budworm as well as other chewing insects, but it is toxic to honeybees and must be applied frequently. The safest, most environmentally-friendly remedy is to use Bacillus thuringiensis (BT), a biological control that is widely available. This spray contains bacteria that kill the worm two or three days after it feeds on the treated plant.
Both of these products will probably require repeated applications. Be sure to follow the manufacturer’s directions.
Q. We’ve had no luck with the hummingbird feeder that we’ve put out and tended diligently. All that it has attracted are ants. Now I want to try planting flowers that will attract them. Can you suggest some likely plants?
A. Hummingbirds can be fickle when it comes to artificial feeders. While some people have excellent luck with the feeders, others don’t. As for the ants, I’ve found that keeping the hanger greased with petroleum jelly or Tanglefoot keeps those pesky ants from reaching the hummingbird feeder itself.
Fortunately, hummingbirds are attracted to plants that are rich nectar sources, and there are lots of choices. Entire books have been written on attracting hummingbirds to the garden with extensive lists of plants. Nevertheless, a trip to your local garden center will provide you with some readily available choices.
Hummingbirds are attracted to the blossoms of citrus, redbud and mimosa trees, shrubs such as grevillea, hibiscus and rosemary, and vines like honeysuckle and trumpet vine. A friend reports that the hummingbirds literally fight over the blossoms on her salvia plants.
When in doubt, look for plants with…