MAY
2009

 

 

 

By
B. Rosie Lerner
 
Purdue
Extension
Consumer Horticulturist

 

 

 

 

 

05-07-09

Question and Answer

Q. Could you tell me what kind of weed is creeping through my lawn and flowerbeds? It has scalloped edges on the leaves and pretty blue flowers. The leaves have a strong smell. I have tried all kinds of weed killer on it; I think it makes it grow!

A. You and most every gardener in Indiana are doing battle with the common perennial weed called ground ivy, aka creeping Charlie, a member of the mint family. It is indeed a challenge to get this vigorous invader under control. The horizontal stems called stolons creep along the ground, rooting at the node where the leaves join the stem, thus making new plants. Repeated digging and pulling will help, but small pieces left behind can make remarkable recovery. A flame weeder might help at least knock it back, if you can keep the flame safely away from desirable plants. If the ground ivy is growing amongst your ornamental shrubs and flowers, any herbicide that would provide even limited control of the weed is likely to cause more damage to your desirable plants than the ground ivy! For more information on control in your lawn, take a look at http://www.ppdl.purdue.edu/ppdl/weeklypics/5-24-04.html.

Q. Three years ago, I planted two crape myrtles in my yard and one across the drive approximately 600 yards away. The one 600 yards away blooms every fall. The other two in my yard leaf out but won't bloom. Can you tell me why the two won't bloom?

A. There are a number of reasons why crape myrtle may fail to bloom, including lack of maturity, inadequate sun exposure, pruning at the wrong time, cold injury and excessive nitrogen fertilizer. Three years is not very old, perhaps the two non-bloomers need a few more years to mature. Crape Myrtles flower on new season's growth, so pruning in late spring or early summer will remove flower buds. If the plants in your yard are in a fertilized lawn, the nitrogen could delay production of flower buds. There are many different selections of crape myrtles, many of which are only marginally hardy to Southern Indiana. The U.S. National Arboretum has an excellent article at http://www.usna.usda.gov/Gardens/faqs/crapemyrtlefaq1.html.

Q. My cousin has five mastiff dogs. He fertilizes his vegetables with mastiff dog poop. Is this healthy? Is it safe to eat the veggies?

A. Here's the scoop on the massive mastiff poop. Manure from dogs, cats and pigs should not be used at all in gardens or compost because it may contain parasites that can infect humans. Other animal manures may be used safely if composted for at least 6 months before applying to the garden.

Fresh manure poses a high risk of causing illness to the gardener, as well as anyone eating fresh produce from that garden. Fresh manure can also be harmful to growing plants, due to being too high in available nitrogen, thus burning roots.

All animal manure poses some risk due to pathogens, including E. coli, salmonella, and listeria, which can be transferred to humans. Some animal manure may also contain parasites, such as roundworms and tapeworms.

Root vegetables and other crops whose edible portion is harvested from below ground pose the greatest risk of transmission, since they have the most contact with potentially contaminated soil. Leafy vegetables, such as lettuce, spinach, cabbage, chard and other greens where the edible portion is in contact with soil, and especially crinkly leaves that catch soil particles are also at high risk for contamination. Thorough washing, peeling root crops and removing outer leaves from heads of lettuce and cabbage will reduce risk. Thorough cooking is the only way to eliminate the risk completely.

 

 

Writer: B. Rosie Lerner
Editor: Olivia Maddox,