Grumpy Answers Your August Gardening Questions
It's hot out there, but someone has to care for the garden.
1. I planted two sweetshrubs because I love the fragrance, but the blossoms have no scent whatsoever. I'm trying to decide whether to replace them and was hoping for input from you. —Karen
Grumpy Says: Not all sweetshrubs have fragrant flowers. That's why you should either choose them when they're blooming so you can sniff them first or buy a named selection that's known to have a strong scent, like "Athens" or "Aphrodite." If it's fragrance you want, replace your shrubs or just spray them from time to time with your favorite cologne. Grumpy prefers English Leather.
2. What happened to the delicious tomatoes of my youth—red, juicy, and firm with an acid snap to the taste? I'm growing tomatoes in a large container in full sun. The flavor has some acid, but the inside still has a mealy texture. What can I do next year to get the taste of old summers that I crave? —KT
Grumpy Says: If taste and texture are what you want, then you need to plant heirloom tomatoes like "Cherokee Purple," "Arkansas Traveler," "Mortgage Lifter," "Black Krim," and "German Johnson." Many garden centers now sell them as transplants. Or you can order seeds from tomatogrowers.com.
3. How can I rid my yard of mimosa trees? My dear neighbor brought three of these trees from her family's home in Luray, Virginia, and planted them in her yard. They seem to sprout EVERYWHERE around my garden. I've even poured full-strength Roundup on them before, but some have since resprouted. —Diana
Grumpy Says: As long as you have bloom-size mimosas in the vicinity, you will have baby mimosas sprouting in the yard. They're easy to get rid of. Just pull up the tiny seedlings. For bigger trees, spray with Roundup according to label directions. This does not mean pouring full-strength Roundup on them. I know it may sound counterintuitive, but straight Roundup kills the leaves before they can transport the chemical down to the roots. So seedlings treated this way will resprout.
4. My husband and I moved to South Carolina six years ago and bought a weeping cherry tree. It has done beautifully until this summer. It appears to be dead at the top, but other growth has come up at the root base. —Joan
Grumpy Says: I'm afraid I have bad news. Weeping cherries are really two different trees grafted together—the weeping part and the trunk and roots. If the weeping part dies, what you get is a wild cherry tree that is totally different. I'd replace the tree with a new weeping cherry this fall.
5. Will bottled water hurt my plants? Occasionally, a half bottle gets poured out into a flowerpot. —Rebecca
Grumpy Says: No, bottled water will not hurt your plants. Be sure not to use moonshine by mistake, however, or they will keep you up all night with their singing.
6. A guy just gouged a big hunk out of the trunk of my pretty, old crepe myrtle with his car bumper. Is there anything I should apply to the wound? —Arlene
Grumpy Says: I assume you mean the wound in the crepe myrtle and not the one you're gonna leave in the driver's head. Painting the wound with something may make you feel better, but it won't really help the tree. In fact, it could delay healing. What you need to do is take a sharp knife and slice off any shredded or loose bark around the wound. Then let the tree heal itself. This may take a couple of years. It should eventually be okay, unless next time it gets hit by a bus.
7. We've been growing half-runner green beans for 60-plus years. This year, there is a pest that rolls up the ends of the leaves. When we look closely, we see a worm inside. What will get rid of it without hurting the beans? —Marie
Grumpy Says: Sixty-plus years? Forget pomegranate juice and spinach shakes—eat more beans, people! The caterpillars rolling up the leaves are called "leaf rollers." (I know…crazy, right?) To get rid of them, pick off and squash all rolled leaves. Then spray your plants with a natural pesticide called spinosad.
8. My 2-year-old French hydrangea (Hydrangea macrophylla) has lots of leaves but has never flowered. It gets morning sun and afternoon shade, and I've fertilized it. Any suggestions? —Bram
Grumpy Says: Sometimes a cold winter will kill the flowerbuds, which aren't as hardy as leaf buds. So no flowers. Another possible cause is incorrect pruning, which shouldn't happen later than July or you may prune off next year's flowerbuds.
9. Why are my tomatoes black on the bottom? —Lela
Grumpy Says: This is a condition called "blossom-end rot" that results when the plant can't absorb enough calcium from the soil. To prevent it, sprinkle a cup of lime around each plant and water it in. Also, mulch your plants to help keep the soil moisture consistent so roots function properly. Blossom-end rot may also affect peppers, eggplants, squash, and cucumbers.
10. We live in the part of Texas where the preferred lawn grass is St. Augustine. My husband inadvertently sowed some Bermuda grass seed, and now we have a terrible mixture. Is there any way to remove the Bermuda? —Dorethea
Grumpy Says: Unfortunately, anything you spray to kill the Bermuda will kill your St. Augustine too. So take a different tack: Mow your lawn high—3 to 4 inches. At this height, St. Augustine will shade and outcompete the Bermuda, making it less noticeable.
11. We're moving from the Northeast to South Carolina, and people say we'll have "gumbo" soil. What will I need to add to allow me to grow flowers? —Mary
Grumpy Says: In the garden, "gumbo" isn't an okra-based soup with added crawfish. It's blackish soil composed of very fine silt that becomes gummy when wet. Because it drains poorly, many plants turn up their noses at it. The best solution is to mix in lots of organic matter such as chopped leaves, ground bark, and composted manure before planting. Season with peat moss to taste.
12. Can I plant a lemon tree outside my house in Myrtle Beach, South Carolina? —Pat
Grumpy Says: You can, but because a lemon tree won't take well to freezing weather, it will have to be in a container that you can bring inside and place by a sunny window during winter. I recommend a selection called "Improved Meyer." Make sure the pot drains well, and empty the saucer after you water. Feed approximately every three months with a fertilizer labeled for use on citrus.
13. What can I do to encourage my "everblooming" azaleas to bloom more? They didn't bloom this spring, and it doesn't appear that they've set buds for fall either. Should I just replace them? —Sandra
Grumpy Says: First of all, there is no such thing as an "everblooming azalea." That's just marketing hooey. There are repeat bloomers, like the Encore azaleas that bloom heavily in spring and fall and sporadically in summer. Be patient. It sometimes takes a year or two in the ground before plants start doing their thing. Fertilize in spring with a product for acid-loving plants, such as Espoma Holly-tone. Prune, if necessary, only after the spring flowers fade.
14. I inherited a very large Christmas cactus that's 49 years old. Now it appears to be dying. Some stems are very soft to the touch and breaking off at the base. What's wrong? Can it be saved? —Jayne
Grumpy Says: You had better not kill that grand, old plant or Grumpy will be especially peeved! It appears you're overwatering it, which is the quickest way to kill a Christmas cactus. This plant likes the soil to dry out between waterings. I keep mine outside in the shade all summer and water no more than once a week. If the pot has a saucer beneath it, make sure to empty it after each watering.
15. Black, sooty mold is now covering the leaves of my gardenias and crepe myrtle. I have read your column for years and years and refer to it very often. You always have the answer. —B.J.
Grumpy Says: It's a gift, B.J., one that I feel a great responsibility to share with humanity. The sooty mold is a fungus that grows on the sticky honeydew secreted by insects such as aphids that suck sap from the leaves. Spray your plants according to label directions with neem oil, horticultural oil, or insecticidal soap. Get rid of the insects and the mold will go.
WATCH: The Best Way To Compost
16. I have discovered large, maggot-looking creatures in my compost barrel. All I've added to the compost lately is rabbit droppings via my children's new pet rabbit. Should I be alarmed? —Kevin
Grumpy Says: The maggots won't hurt anything, just look gross. However, in the future, don't put pet droppings in the compost. They may carry parasites and also attract critters.
17. In 2011, I bought nine 'Endless Summer' hydrangeas. The world was beautiful. Fast-forward to 2014. I fertilized, added aluminum sulfate, pruned, and got two blooms. What happened? —Charles
Grumpy Says: 'Endless Summer' hydrangea may rebloom, but it isn't really a tough plant. It needs frequent watering and periodic feeding to keep it blooming in the South. Grumpy doesn't have that kind of time, so he prefers a hydrangea called 'Little Lime.' It is much easier to grow; matures at 3 to 4 feet tall; sports showy, white summer blooms that turn pink in fall; and tolerates heat, sun, and drought like a trouper.
18. We've had lots of rain this summer, and the foliage of our asparagus plants is already turning brown and dropping. Do you think they'll come back, or should we replant this fall? —Sharon
Grumpy Says: I hate to bear bad tidings (it's so against my nature), but the problem sounds like asparagus crown rot. The disease that causes it lives in the soil, so if you plant asparagus in the same place, you'll get crown rot again. That would make you terribly unhappy. Just pick a different spot, and start over.
19. I don't care for elderberry bushes. They spread quickly and are hard to kill. Why should I love them? —Robyn
Grumpy Says: You should love American elderberry (Sambucus canadensis) because it's native, provides food for wildlife, and (most importantly) both its berries and its flowers can be used to make wine. You can also enjoy the fruit in pies, jams, and jellies. Cheers!
20. We live in Baton Rouge, Louisiana, and my husband wants to grow a giant pumpkin. What kind should I plant, and how do we do that? —Frances
Grumpy Says: Sorry—it's too late this year. In order to grow a gigantic gourd, you must start 'Atlantic Giant' pumpkin plants in spring. The vines like fertile, moist, well-drained soil and full sun. They'll spread all over, so you'll need lots of room. Let each vine ripen just one giant pumpkin. Then paint it LSU purple and gold. You know you want to. Laissez les bons temps rouler!
21. I made the mistake of planting chocolate mint in my vegetable garden. It's taken over everything, and I can't get rid of it. Do you have any solutions? —Carol
Grumpy Says: All mints, including the yummy chocolate kind, are thugs. They spread by rhizomes and engulf everything around them unless planted inside beds or containers from which they can't escape. This problem doesn't have an overnight fix. You'll need to keep pulling the plants. Also get a spray bottle of Roundup and spot treat the mint according to directions. Just don't spray your good plants!
22. Ants have taken up residence in my potted rose and herbs on my second-story balcony. How can I get rid of them without harming my snoopy cat? —Sandi
Grumpy Says: The ants aren't feeding directly on your plants. Instead, they're placing aphids on the leaves and "farming" them. The aphids suck the juice and secrete a sweet honeydew that the ants drink. Try placing some ant traps in all of your pots. You can get them at home-and-garden centers. They attract and kill ants but don't harm anything else.
23. Suckers from black gum trees keep sprouting in our lawn. We've tried pulling them up to no avail. How can we kill them? —The Trotters
Grumpy Says: These suckers likely come from roots of black gum trees that were cut down. Spot treat the suckers with Roundup or Brush Killer Plus. Or just mow them down when you cut the grass. Eventually, the roots will die.