Having trouble with your summer vegetable garden? Grumpy has the answers.

Overwatering Watemelons
Credit: Michael Witte

1. This is our first year growing watermelons. There are lots of melons, but they're starting to rot at the bottom and one burst open. It's been hot, so I water twice a day. Too much? —Barbara

Grumpy Says: The problem is too much water in too little time. This makes the melons quickly swell up and split. Besides backing off on the watering, place some pine straw mulch under the ripening melons and all around the plants. Mulch keeps the soil from drying fast, so you won't have to water as often. It also prevents melons from lying on the soil and rotting. Water only when the leaves look a little wilted in the morning. Then water thoroughly.

2. Can you recommend a noninvasive, fast-growing, sun-loving evergreen ground cover to replace a deeply sloped front lawn in USDA Zone 7? Don't want much, do I? —Vinette

Grumpy Says: Fortunately, Grumpy is the ultimate giver. One ground cover that meets your criteria is creeping juniper (Juniperus horizontalis). A few popular selections include "Bar Harbor," "Icee Blue," "Prince of Wales," and "Wiltonii."

3. I have one of my favorite aunt's African violets. It has split into two little trunks and turned into two plants. I know it needs to be repotted, but I don't know how to do it safely. Could you help me? —Marsha

Grumpy Says: Your plant needs to be divided. Take it out of its original pot. You'll see two "crowns," tufts of leaves attached to roots. Insert a knife between the crowns and "trunks," and divide the roots so that each crown has its own root system. Then pot them separately.

4. HELP!! Tomato worms are devouring my tomato plants. Do you have any information on their life cycle so I might be able to stop them in the future? —Barbara

Grumpy Says: Okay, I'm not gonna wimp out on this answer, caterpillar lovers! The culprit here is most likely the tobacco hornworm, a very large, green caterpillar, 3 to 4 inches long, with diagonal white stripes and a curved, red spine on the rear. (Tomato hornworms look nearly identical, but they're more common up North and have a black spine.) Both are the larvae of large, grayish brown moths. These hornworms feed on tomatoes, potatoes, eggplants, peppers, and tobacco. Because they're green, you often don't see them before they've devoured half the plant. Control them by picking them off and squashing them or spraying plants according to label directions with either of two natural controls: spinosad or Bacillus thuringiensis (DiPel). These garden-center products work better on hornworms that haven't yet reached their full size, so be vigilant.

5. How do I get rid of little house ants? —Marcy

Grumpy Says: Arsonists find that setting the place on fire works well, but then they go to jail. So I would use Terro Liquid Ant Baits (available at terro.com). They contain a slow-acting poison that foraging ants carry back to the nest and share with their buddies and queen. Also seal anything sweet (sugar, honey, syrup, etc.) inside plastic ziplock bags so ants won't be lured by them.

6. What is that sticky stuff that drips from crepe myrtles all over my deck, plants, and tables? We have trouble with it every summer. —Janet

Grumpy Says: It's honeydew secreted by insects that suck sap from the leaves, and the culprit is probably aphids. To kill them, spray your trees according to label directions with horticultural oil, neem oil, or insecticidal soap, all widely available.

7. Our green beans came up beautifully, but now they have a rusty look. Should I remove them to keep this condition from spreading? —Kathy

Grumpy Says: Bean rust is a fungus that causes yellow and orange pustules to form on leaves and beans. It spreads very quickly in rainy weather and can take down an entire crop. If it's all over your plants, pull them up, throw them out with the trash, and start over. (No worries—beans grow fast.) If it's not, spray them according to label directions with Natria Disease Control or Bonide Liquid Copper Fungicide. You can get these products at garden centers. Spray healthy seedlings too. If you want to prevent buildup of disease spores, don't plant beans in the same spot every year. Crop rotation is good for all veggies, especially tomatoes, potatoes, peppers, squash, cabbage, and broccoli.

Painted Tomatoes
Credit: Michael Witte

8. Why won't my tomatoes turn red? This is keeping me up at night. —Deanna

Grumpy Says: Look on the bright side, Deanna. At least now you can watch Jimmy Fallon in real time. Not a comfort? Then consider these reasons why tomatoes can be slow to ripen: First, it's still early summer, so your plants may need a few more weeks; second, unseasonably hot weather or a heavy fruit-set can stress your plants and delay ripening. Spreading a 1-inch layer of mulch under your plants will help by cooling the roots and keeping them moist. The bottom line: Be patient.

9. Is there a way to keep suckers from sprouting at the base of my crepe myrtle? I keep cutting them off, but then they regrow. —Marcia

Grumpy Says: If the suckers are growing from a knob on the trunk, just cut off this knob flush with the trunk and the suckers won't return. However, if the suckers are growing from the roots, all you can do is cut them off at the ground whenever they appear. The older a crepe myrtle gets, the fewer root suckers it generally produces.

10. My yellow creeping Jenny came out beautifully this spring and then withered and died. My neighbor's looks fine. What could it be? —Maggie

Grumpy Says: Sounds to Grumpy like your creeping Jenny fell victim to a creepy fungus called Southern blight. A cottony mass between the stems and soil is a sure sign. No fungicide cures this. The best thing to do is prevent the fungus from getting started by providing good drainage and watering only in early morning.

11. I bought basil plants two weeks ago, but something is eating holes in the leaves. What can I do? —Judy

Grumpy Says: Snails and slugs that work at night are the most likely culprits. Try using Monterey Sluggo Slugs & Snails, which contains iron phosphate, to kill off these slimeballs. It's safe for use around pets and wildlife and available from amazon.com. Another natural control is diatomaceous earth. This powdery product cuts the soft skins of these pests so they ooze to death. Fun!

Loropetalum Hedge Funeral
Credit: Michael Witte

12. I over-trimmed our loropetalum hedge. I'm afraid I killed it. My wife is gonna kill me! What can I do other than hide? —Allen

Grumpy Says: Well, if she's gonna kill you, it won't be because of the loropetalums. These tough plants adapt well to even bad pruning, so if you leave them alone, they'll fill out. FYI, the best way to keep hedges full and thick is to make them wider at the base than at the top, so sunlight reaches all of the leaves near the ground and the plants don't get leggy.

13. I'd like to line my driveway with some eye-catching plants but am concerned my neighbor's utility lines might be there. Any suggestions? —Laura

Grumpy Says: If you're one of those fussbudgets who frown upon getting blown up or electrocuted, call 811 before you dig. Tell the operator where you're planning to dig, and they'll send out a locator to mark where underground water, gas, and electrical lines are so you can avoid them.

14. How can I get rid of grass in my flowerbeds without all the hoeing and digging? —Sandy

Grumpy Says: Spray your beds according to the label directions with Ortho Grass-B-Gon. This product will kill only the grass and not your flowers.

15. I have a gorgeous and very tall native azalea. Most of its lower leaves have fallen off, some of the lower branches have died, and new leaves appear only at the top. Should I prune it back to re-energize it? When? —Beth

Grumpy Says: What you have is a mature native azalea. Ordinarily, it makes most of its new growth at the top of the plant, so there is nothing wrong with yours. If you want a bushier plant, cut it back. But don't wait long to do it or you'll cut off the forming flowerbuds. Another way to avoid this problem is to prune after it blooms next spring.

16. Why do you say to drill a hole in the bottom of a flowerpot? What will happen if I don't? —Kyle

Grumpy Says: To doubt Grumpy is to court disaster. Pots need drainage holes at the bottom to let excess water escape; otherwise, your plants will drown. We will not speak of this again.

Moving Boxwoods
Credit: Michael Witte

17. I have a 12-foot-tall boxwood hedge that needs to be moved now. What's the best way to do this? —Rosanne

Grumpy Says: I have good news and bad news. The good news is boxwoods that big are worth a fortune. The bad news is that if you move them in warm weather, you'll kill them. So wait until November. And be sure to hire a professional to do the job.

18. What's that white powdery stuff on the leaves of my crepe myrtles? How do I get rid of it? —Charles

Grumpy Says: Grumpy used to think it was baby powder to prevent chafing. But it's really a fungus called powdery mildew. Many popular crepe myrtles such as 'Natchez,' 'Miami,' 'Red Rocket,' and 'Catawba' resist it. But if mildew shows up on yours, spray according to label directions with neem oil, Natria Disease Control, Daconil, or Immunox.

19. My hydrangeas will not leaf out on the old wood. All new growth comes from the bottom. Is this because we had a warm spell in early spring followed by a sudden freeze? —Janet

Grumpy Says: Exactamente! The unseasonably warm weather woke up the hydrangeas too early, and then the later freeze killed your plants to the ground. There's no lasting damage, though your plants may not bloom this year. Cut off the dead branches, and let new growth come up.

WATCH: Why Didn't My Hydrangeas Bloom?

20. I'm trying to grow prizewinning pumpkins. I started seedlings in a tray and then transplanted them to big containers. The last transplant caused them to wilt completely. How can I minimize shock? —Isabel

Grumpy Says: Forget about growing those 800-pound behemoths. You can't do that in containers. Each giant pumpkin plant needs about 400 square feet of garden, and you get only one pumpkin per plant. Instead, sow seeds of small-fruited kinds (5 pounds or less) such as 'Small Sugar,' 'Jack Be Little,' and 'Baby Boo' directly into the pots in spring.