Q Are Mexican petunias invasive with deep root systems? If I put them in a pot, will that work?
A Mexican petunia is a plant in the Ruellia genus. There are several different varieties available, and some are more aggressive than others. The standard Mexican petunia is Ruellia brittoniana, and it can spread if given a chance, especially in good soil with ample water. While containing the root system in a pot will keep its roots from spreading, it still has the potential to seed itself. Its more diminutive cousin is dwarf Ruellia often sold under the name "Katie." Another slow-growing, easy-care Ruellia is a small-flowered red variety called "Ragin Cajun." The butterflies love them all, and so if you do grow the large one, learn to recognize it and contain it if it begins to spread.
Q I have an American persimmon tree with an Asian graft that is about 7 years old. It was damaged during a storm this spring, and a huge part of the trunk was wounded. Is there anything I could do to nurse it along?
A Unfortunately, I do not think the tree is worth salvaging from the wound up. From the picture you sent, I am guessing the damage is done beneath the graft union. In my opinion your best bet would be to cut it off at the soil line and then choose the strongest sprout to retrain as a tree. Or buy a new tree. Once it has grown, you could graft a stem of an Asian variety onto it. The wound is so large that even if the plant somehow survived, it would be hollow and weak the rest of its life.
Q I came upon a lovely hardwood trellis at a thrift shop that I compulsively bought, imagining its placement on one of the posts under the gazebo on our deck. I pictured a flowering vine. Then I got to thinking: This past winter I lost a few well established plants that were living on the deck even though they were well "mulched-in" for cold weather (no roots in the ground as the deck is well above ground). I hate the look of dead or dying plants during the winter. Is there an evergreen vine out there that will keep its look during the winter and brave some really low temps -- as well offer up some really nice blooms during spring and summer? The post I am wanting to dedicate to this is southwest facing and gets some pretty strong afternoon sun, but maybe only three or four hours worth a day.
A I would consider Confederate jasmine (Trachelospermum jasminoides) or Carolina jasmine (Gelsemium sempervirens). Neither are true jasmines but both bloom on evergreen vines. I have a Confederate jasmine that grows in full sun exposed on the west side of my brick chimney and it has had no winter damage even this past winter.
Q We suddenly lost a crape myrtle; maybe you can tell us why. It was a thriving, well-cared-for tree that had been bought and planted in our garden a couple of years ago. We were gone for all of May this spring. When we came back, all the foliage was gone and the bark cracking; new shoots had appeared in abundance from around the base. In less than a 100 feet, there is a Bartlett pear that appears to have fire blight. Our other theory is gophers. They love our garden and are quite destructive. A young redbud in the garden near the crape myrtle had also died. There had been adequate rain while we were gone. Hope you can suggest why this happened.
A Whenever I hear tales of multiple species suffering similar fates, I usually suspect chemicals or something physical. I can't see a gopher killing an established crape myrtle overnight, nor a redbud. While it has been dry off and on, it hasn't been dry long enough to kill a crape myrtle. I would assess what has been sprayed nearby and do some investigating. Take pictures of all the plants affected and take some samples of the damage to your local county extension office. Identifying the problem is the first thing to do before removing or replanting.
Janet B. Carson is a horticulture specialist for the University of Arkansas Cooperative Extension Service. Write to her at 2301 S. University Ave., Little Rock, Ark. 72204 or email her at
jcarson@arkansasonline.com
HomeStyle on 06/30/2018