The multi-stemmed flowering shrub, hibiscus syriacus, is better known by its common name, the Rose of Sharon. It's deciduous and grows into a vase-like shape and hails from India and China. And because it's related to the hardy hibiscus, it grows well in our region.
If you're looking to add height, drama and a range of color to your landscape, Rose of Sharon might be a good fit. The shrub can grow from 10 to 13 feet tall and the blossoms come in a range of hues.
One of the larger varieties is called Chiffon and will blossom with white, red, pink or blue-colored flowers. Its flowers are edible, too!
For smaller spaces, try Little Kim, or a variegated variety like Sugar Tip, which grows up tall and narrow, like a purple pillar.
Rose of Sharon make for great plants to put in the landscape and they flower in late summer. Place them in full sun with well-drained soil and, if you can, give them their own spot on the lawn or in the garden. They'll need some room.
As for pests that could bug these flowering shrubs, luckily, there aren't many. Japanese beetles may go after them but those are controllable by using beneficial nematodes in the soil to go after larvae and grubs.
Do note that some of the older Rose of Sharon varieties self-sow. That is an issue, especially in the southeast, where the plants can become invasive in the landscape. If you want to avoid your plants from self-sowing, deadhead all the flowers when they're done blooming.
Another way to ensure they won't self-sow is to choose varieties that are hybrids, like Sugar Tip or those in the Minerva series. These have sterile seeds and won't self-sow.
Will the cardinals take care of the tomato hornworms?
Q: I have been watching and picking off tomato plant stems that were getting spotted, yellow and withered. I assumed the very rainy weather had over-saturated the soil and caused this. However, today I watched a male cardinal rummaging around in my tomato plants (in a tall raised bed). I went out to see what he was up to and discovered my first tomato hornworm proudly hugging a tomato plant stem; they blend in quite well ... I removed the hornworm by putting it into a container of soapy water before it could destroy all of my tomato crop. Would the cardinal have eaten the hornworm or the hornworm eggs? Did I disrupt the natural world? - Lee, in Richmond
A: Because of the sheer size of adult tomato hornworms, a cardinal might find that too daunting of a meal!
Regardless, you should go ahead and keep pulling the hornworms off your tomato plants. Dropping them in the soapy water is a good way to get rid of them.
Beetle traps no longer recommended
Q: I was alarmed to hear the recommendation of Japanese beetle traps in the always interesting All Things Gardening. My personal experience of using these at a past residence, and with neighbors of my present home, is that if there is a trap anywhere in the area, the number of Japanese beetles in that area will greatly increase. While the traps cull many, they attract so many, many more, and the result is terrible for everyone in the neighborhood ... I urge that the recommendation of these traps be rescinded, or at least offer strong wording that these traps can be counterproductive and devastating to a property and its neighbors, and specific guidance as to where these might be used without regional harm (if that is possible at all). - Tom, in Georgia
A: Thanks for alerting us, because yes, you are correct about Japanese beetle traps. Most extension service and university sites no longer recommend the traps anymore, because the evidence shows they bring in more Japanese beetles than they actually trap.
You might want to use some other methods, like beneficial nematodes this fall, or just simply doing more handpicking. And thanks, Tom, for keeping us on our toes!
Lilac blight or powdery mildew
Q: My lilacs appear to have a significant case of blight. Is it worth heavily pruning them and hoping they'll return next year? Or should I get rid of them completely? - Christina in Burlington
A: Don't get rid of your lilacs! Instead, treat the issue that is plaguing them and this year, there are two.
One of the diseases is powdery mildew, because of the wet weather. When that affects lilac bushes, you'll see the lilac leaves yellow and curl up. It's ubiquitous in the environment and gratefully, not one to really worry about. In wetter years, it can get worse.
The other issue affecting lilacs this year is blight. That's a bacterial disease that makes lilac bushes' leaves look like they've been scorched and turn brown.
Blight is more contagious than powdery mildew and a bit more of a concern. You can help your lilacs out, though, by cleaning up the leaves as much as you can and removing the leaves from the environment so as not to continue to spread the blight.
If we have a dry spring and summer next year, blight won't be an issue. If it's wet, though, you might try to get ahead of the blight and spray your lilacs with an organic spray to knock it down before it gets going.
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