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By Dennis Bishop and Dennis Bishop,Special to the Sun | July 8, 2001
Q. Every year my annual verbena becomes covered with a white powdery substance that I assume is powdery mildew disease. What can I do to avoid the disease? Can it be treated? A.Powdery mildew is a fungal disease that is difficult to avoid when conditions are favorable for it. Some cultivars of annual verbena are less susceptible to powdery mildew than others; however, the problem is generally so serious that I do not recommend annual verbena for planting in our area. I would recommend planting the perennial verbena 'Homestead Purple.
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By Ellen Nibali and David Clement | October 6, 2007
My yard is being overtaken by wild strawberries. How do I eliminate them without killing what grass is left? Do they have yellow flowers? Your wild "strawberries" are probably not strawberries at all, but an alien plant called Indian (as in India) strawberry that masquerades as a strawberry. (Real wild or domestic strawberries have white flowers.) To get rid of this invasive weed, use a weed killer formulated only for broad-leaved weeds containing triclopyr, alone or combined with dicamba, MCPP and 2-4D.
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FEATURES
October 11, 1998
Q. I've finally learned what powdery mildew looks like, and I'm sure I have it on my lilacs, dogwoods and crab apple trees. How bad a disease is it and what should I be doing about it?A.Powdery mildew is a generic term for several fungal pathogens that attack a wide range of plants at different times of the growing season.Powdery mildew that arrives late in the season on lilacs will not harm your plants. It's unsightly, but no action need be taken. As for dogwood and crab apple trees, powdery mildew attacks blooms and new foliage early in the season.
FEATURES
By Ellen Nibali and David Clement and Ellen Nibali and David Clement,Special to the Sun | August 18, 2007
My outdoor Hibiscus moscheutos is being eaten up. I love the plant and hate to see it this way. Is there is something I can do? Larvae of the hibiscus sawfly are difficult to detect, because they are the same color as leaves and feed underneath. They may have finished feeding by now, but if you still find them in numbers, you can spray with insecticidal soap, horticultural oil or Spinosad. Be sure to spray when it's below 85 degrees and use a summer dilution rate for soap or oil. Or knock the larvae off into a bucket of soapy water.
NEWS
By Kathy Van Mullekom and Kathy Van Mullekom,Knight Ridder / Tribune | June 30, 2002
If you like a long-blooming, disease-resistant perennial, you'll want to turn some garden space over to a phlox called David. Best of all, he'll attract lots of butterflies to your gardens. In addition, you'll have an award-winning plant among your perennials because Phlox 'David' has been named the 2002 Perennial Plant of the Year by the nonprofit, educational Perennial Plant Association. The perennial -- Phlox paniculata, a member of the Polemoniaceae family -- is native from New York to Georgia, and it's cold-hardy in Zones 4-9. 'David' grows upright, reaching 36 to 40 inches tall, but it produces strong stems that stand sturdy in wind and weather.
FEATURES
By Ellen Nibali and David Clement and Ellen Nibali and David Clement,Special to the Sun | August 18, 2007
My outdoor Hibiscus moscheutos is being eaten up. I love the plant and hate to see it this way. Is there is something I can do? Larvae of the hibiscus sawfly are difficult to detect, because they are the same color as leaves and feed underneath. They may have finished feeding by now, but if you still find them in numbers, you can spray with insecticidal soap, horticultural oil or Spinosad. Be sure to spray when it's below 85 degrees and use a summer dilution rate for soap or oil. Or knock the larvae off into a bucket of soapy water.
NEWS
March 11, 2001
Q. How do you get rid of fire blight in sweet cherry trees? At least that's what I think is wrong. Last summer, some of my young shoots wilted and died and one branch died back. I want to prevent the problem this coming season. A. Cherry trees don't get fire blight. You may have a couple of different problems. Oriental fruit moth larvae may have entered the young shoots, causing wilting and death. Or the shoots may have been damaged by very cold temperatures. The branch dieback was probably caused by a canker disease.
FEATURES
By Ellen Nibali and David Clement | October 6, 2007
My yard is being overtaken by wild strawberries. How do I eliminate them without killing what grass is left? Do they have yellow flowers? Your wild "strawberries" are probably not strawberries at all, but an alien plant called Indian (as in India) strawberry that masquerades as a strawberry. (Real wild or domestic strawberries have white flowers.) To get rid of this invasive weed, use a weed killer formulated only for broad-leaved weeds containing triclopyr, alone or combined with dicamba, MCPP and 2-4D.
FEATURES
November 17, 1996
I have two flowering dogwoods that looked droopy and peaked this summer. The leaves had a white powder on them. Should I be worried? Is the problem wet weather?The problem is a fungal disease called powdery mildew, which is more widespread during wet growing seasons. This is not a devastating disease, like dogwood anthracnose, but should be controlled when symptoms are severe. If symptoms reappear next year, spray foliage thoroughly with a horticultural oil that is registered for use against powdery mildew.
FEATURES
August 18, 1996
I can't wait to come home from work and unwind beside my water garden. But my hardy waterlilies are closed by late afternoon. Is there any way to prolong their blooming time?Night-blooming tropical waterlilies would be perfect for your water garden. Blossoms remain open from late afternoon until midmorning of the next day. Many are fragrant, their sweet scent perfuming the night air. They also make wonderful cut flowers.Tropical waterlilies are not cold-hardy, however, and should be considered annuals.
NEWS
By SUSAN REIMER and SUSAN REIMER,SUN COLUMNIST | June 11, 2006
There is a picket fence around my cozy two-story house, and just inside its borders is my version of an English cottage garden. My crispy, wilting, gasping version of an English cottage garden. It is only June, but summer has hit Maryland like a brick in the nose after a very dry spring, and my plans for a lush and riotous perennial border are fading in the heat. "When are you going to realize that we don't live in England?" asked Bob, my neighbor and gardening mentor, as he looked over my foxgloves.
NEWS
By Kathy Van Mullekom and Kathy Van Mullekom,Knight Ridder / Tribune | June 30, 2002
If you like a long-blooming, disease-resistant perennial, you'll want to turn some garden space over to a phlox called David. Best of all, he'll attract lots of butterflies to your gardens. In addition, you'll have an award-winning plant among your perennials because Phlox 'David' has been named the 2002 Perennial Plant of the Year by the nonprofit, educational Perennial Plant Association. The perennial -- Phlox paniculata, a member of the Polemoniaceae family -- is native from New York to Georgia, and it's cold-hardy in Zones 4-9. 'David' grows upright, reaching 36 to 40 inches tall, but it produces strong stems that stand sturdy in wind and weather.
NEWS
By Dennis Bishop and Dennis Bishop,Special to the Sun | July 8, 2001
Q. Every year my annual verbena becomes covered with a white powdery substance that I assume is powdery mildew disease. What can I do to avoid the disease? Can it be treated? A.Powdery mildew is a fungal disease that is difficult to avoid when conditions are favorable for it. Some cultivars of annual verbena are less susceptible to powdery mildew than others; however, the problem is generally so serious that I do not recommend annual verbena for planting in our area. I would recommend planting the perennial verbena 'Homestead Purple.
NEWS
March 11, 2001
Q. How do you get rid of fire blight in sweet cherry trees? At least that's what I think is wrong. Last summer, some of my young shoots wilted and died and one branch died back. I want to prevent the problem this coming season. A. Cherry trees don't get fire blight. You may have a couple of different problems. Oriental fruit moth larvae may have entered the young shoots, causing wilting and death. Or the shoots may have been damaged by very cold temperatures. The branch dieback was probably caused by a canker disease.
NEWS
By Nancy Brachey and Nancy Brachey,Knight Ridder / Tribune | February 11, 2001
This year, the winners include, of all things, an onion. It's called 'Super Star,' just one of nine flowers and vegetables that won All-America honors for 2001. Each year, the organization All-America Selections of Downers Grove, Ill., heralds the best of new flowers and vegetables from the seed industry. Each has distinct characteristics that set it apart from those already on the market. For example, a new lisianthus named 'Forever Blue' possesses a more attractive, branching shape than ones you may know.
NEWS
By Diana Blowers and Diana Blowers,Cox News Service | July 23, 2000
They may be at the end of alphabetical listings of annuals, but zinnias are at the top of the list when it comes to garden appeal. In late summer, when other flowers are fading, zinnias are just reaching their peak, blooming into October. They grow 6 inches to 4 feet tall and come in every color but blue. Their blooms range from buttonlike heads and daisylike flowers to double blossoms that resemble dahlias. They are American natives, originating as a purplish wildflower from the Southwest United States, Mexico and Central America.
NEWS
January 2, 2000
Q. I have an old, healthy crab apple tree that has become a tangle of branches, many of which are dead or dying. How severely should I prune it to keep it healthy? A. First, prune out all the dead branches. Then remove weak or dying branches, especially those growing across or into the middle of the canopy. If two branches are rubbing, remove the weaker one. Don't simply remove the ends of branches; make your pruning cut back to the next healthy branch or limb. You will probably end up with a lot of wood on the ground, but your tree will live longer as a result.
FEATURES
September 21, 1997
I have two beautiful lilacs with leaves that are covered with a pale white powder. The garden-center people said it was powdery mildew and recommended I buy a rather expensive fungicide to control it. Will this disease hurt my trees, and what is the best treatment?Powdery mildew, a common fungal disease, is usually seen on susceptible lilacs by the end of summer. It sounds as if your lilacs are severely infected, so treatment with a fungicide at this time and again in the spring during budbreak is warranted.
NEWS
By JON TRAUNFELD | July 23, 2000
Q. My yellow squash and cucumber plants are wilting even though I water them every other day. I looked for the squash borer (which I've dealt with in years past) but see no sign of holes in stems. Is there some disease causing the wilt? A. Yes, your plants are probably infected with bacterial wilt disease, which is spread by cucumber beetles. You may notice individual stems wilting during the day and recovering somewhat at night. The disease spreads through the plant's vascular system causing plants to collapse.
NEWS
January 2, 2000
Q. I have an old, healthy crab apple tree that has become a tangle of branches, many of which are dead or dying. How severely should I prune it to keep it healthy? A. First, prune out all the dead branches. Then remove weak or dying branches, especially those growing across or into the middle of the canopy. If two branches are rubbing, remove the weaker one. Don't simply remove the ends of branches; make your pruning cut back to the next healthy branch or limb. You will probably end up with a lot of wood on the ground, but your tree will live longer as a result.
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