Q: I'm a lawn nut, but my dogs' urine leaves ugly yellow dead zones, especially when it's hot and dry. Is there anything that can be done to prevent this?
A: Dogs' urine is high in acid and excessive levels of nitrogen and creates a burn once it hits the lawn. When grassy areas are wet, or even moist, the impact is diluted. That's why dogs and lawns get along better when it rains. If Fido has to go outside, one way to reduce the yellow dead zones is to water everything down with a hose once he's done his business. Then look into a product called NaturVet GrassSaver Liquid, which is a vitamin compound added to a dog's food. There are lots of expensive supplements that claim to neutralize the lawn-burning substances in dog urine, but this is one of the few that works fairly well. If a spot is really bad, you'll have to buy a bit of sod, dig up and replace the poisoned soil with new topsoil, patch the spot, and water every day for a week or two. (Using seed may be a waste of time and money on a lawn with dog traffic.) You can keep the leftover sod on loose, rich topsoil in a sunny spot somewhere behind the garage, and if you keep it wet, it will be useable for this purpose for up to about 10 days.
Q: I have a 30-year-old California Privet hedge that's starting to look a little sickly, but we really need it for privacy. What can I do to make it fill out again?
A: Privets should be pruned and shaped (either rounded off or squared, like a box) once or twice a year. If yours is tall—maybe 10 feet or more—cut it down as much as you can, as this encourages healthy growth. If your hedge is shorter, cut back proportionately, then do some cosmetic clipping later in the year. Make sure it's thoroughly weeded—any weeds or vines will rob nutrients and block light that's essential to the hedge's bottom filling out. Remove spent growth, but leave birds' nests untouched. If the hedge is along a road, make sure the curb area is clear of leaves and debris so that rainwater polluted by automotive oil and fuel don't jump the curb and get into the hedge roots. Privets are hardy, but also need to be watered thoroughly during dry spells. If a larger gap appears, you can plant a new hedge plant (they come four to five feet tall, usually) in the space, and it will happily deal with the breach within a season.
Q: A friend of mine mentioned that certain cut roses can be revived after they've finished blooming in a vase. Is this possible?
A: It's possible: New signs of life often stir within some roses while they're still in the vase. Let's say you receive a dozen roses and put them in a water-filled vase. They last 10 days, then start to fade. Rose petals drop off and leaves dry up. Here's what's needed to bring it back from eternity: rooting solution, a clay pot, light potting soil, and light plastic wrap, available at local nurseries. Once you have everything, select the strongest cane with the most sprouts, deadhead the rose, and cut back the stem to 14 inches. Fill the pot with soil, add one teaspoon of rooting solution, mix in, then insert the cane about 3-5 inches into the soil. Water, and cover the pot lightly with plastic wrap (letting air through), place it by a sunny window, and keep the soil moist at all times. As new leaves begin to sprout, remove the plastic.
Victoria M. Elder, a professional creator of residential gardens, answers frequently asked questions from Baltimore-area gardeners. You can e-mail her with your gardening questions at firstname.lastname@example.org.