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Why Did My Plant Die?

This is the place to read Ketzel's advice to readers' most harrowing gardening challenges from whitefly eradication to weed killer application, lawn alternatives, and bulb care. No matter where you keep your garden, check out the resources available to you locally. Find a shady spot and maybe a helping hand in the Talking Plants Gardens and Arboretums map of the United States.

Here's the Vast and Cavernous Archive of Enquiry that the Doyenne has already answered. Good clean fun for the whole family.

This week's questions:

  • Organic Japanese Beetle Control
  • Caring For An Injured Bradford Pear
  • Mulching Around Peonies
  • Indoor Herbs, Indirect Light? Dubious
  • Moving Plants From State to State
  • Big Dogs and Grass Don't Mix
  • Leave Them Violets Alone!
  • Growing Ginseng

    Organic Japanese Beetle Control

    Dear Doyenne,
    I hate to condemn an ethos, but the Japanese beetles are killing me. They were hanging out on a giant unnamed weed and seemed happy to fall into a trap left from last year when I tapped them into it. I bought new bags and a new bait, but doncha know, the cursed bags don't fit last year's contraption! I taped up the holes in the old bags which they had stretched large enough to escape.

    Then I turned around and they had made lace of the leaves on my new peach tree! I tried to spray them with Safer's Soap laced with cayenne, which stopped up the spray bottle. I put on my antique hose-end sprayer and am not sure that it impressed them because they just kept on "multiplying" and eating. Maybe it was too diluted.

    So, beyond long term prevention and some deadly Ortho product, what can I do at this point to keep them in check?

    Thank you!

    Ah, the joys of East Coast gardening! Can't say I miss those beetles...

    Talk about a broad spectrum approach to control, I'm about to hit you with everything I've heard and know:

    1) Hand-picking! Get out there early in the morning, when the beetles aren't very active, and knock them off plants onto a sheet, then dump the suckers into a bucket of soapy water. Time consuming, but effective.

    2) Use lots of traps, but make sure they are downwind of your yard. Otherwise, the beetles fly through your yard to find the trap and get diverted by plants!

    3) Try to keep the most sensitive plants in full sun; sun leaves are more resistant to attack. Unfortunately, this doesn't help unless you're only now installing plants.

    4) Bearing in mind that stressed plants are attacked more frequently, remove vulnerable ones immediately and keep plants as healthy as possible.

    5) Plant resistant species. Whether or not these plants are your cup of tea, here's a list of genera thought to be resistant to attack, strictly FYI:

    Magnolia, Cercis (redbud), Cornus (dogwood), Acer rubrum (red maple), Quercus rubrum (red oak), Euonymus alatus (burning bush), Ilex (holly), Buxus (boxwood), Tsuga (hemlock), Fraxinus (ash), Chamaecyparis, Taxus (yew), Juniperus, Thuja, Picea (spruce), Pinus, Forsythia, Syringa (lilac), Clematis, and Liquidambar (sweetgum).

    6) Finally, while there are a lot of biological controls available, most of them only attack the grub - too late for this year. Next year consider releasing nematodes, wasps, flies, and other parasites. One fly in particular - Istocheta aldrichi - attacks the adult Japanese beetle (it's all pretty gross, I'll save you the details). I understand that while this control is not yet commercially available, your extension agents may be able to get it.

    Your victory is all our victory! Best, KL

    Read a gardener's difference of opinion.

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    Caring For An Injured Bradford Pear

    Dear Doyenne,
    I live in a suburb of Cincinnati, Ohio. Our 20-year-old Bradford Pear recently had a huge section taken out by an 80 mph wind. The tree survived, but how do I treat the large exposed section where the branch was ripped from the trunk? I am afraid if I leave it exposed it will become a nest for parasites.

    Do nothing! Any kind of wound treatment would be a bad idea. If there are ragged edges, these should be sawn off so the surface is as smooth as possible. The wound will callus over (it does not "heal") and will not be a disease magnet unless the tree is already under some other stress. Be sure, if you are cleaning the wounded area with a saw or pruners, that you sterilize the tools first with Lysol or alcohol to prevent disease transmission from the tool surface.

    All the best, KL

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    Mulching Around Peonies

    Dear Doyenne,
    I have a bed of peonies that I've underplanted with some candytuft, but not nearly enough. And I'm scared to mulch under peonies, because I've read peonies don't do well when mulched. Is there a mulch-like substance I can use to keep weeds away? What perennials do you recommend to accompany my peonies?

    Flummoxed in Montclair, NJ

    The reason peonies don't like to be mulched is that they're easily "blinded" -- that is, if their crowns (and therefore, buds) are buried in mulch, they cannot set bloom. However, this does not mean you can't mulch around the crown leaving the center open. In fact, the best way to do it is to begin mulching two feet out from the base of the plant, where it should be two inches deep, then taper the mulch down to nothing over the crown. Remember that peonies like space, so nearly any perennial that is not too vigorous is fine (just give everyone the proper amount of elbow room). Companion plants? Consider Siberian iris, or day lilies; the strap-like foliage contrasts well with the rounded, bushy forms of peonies.

    Enjoy, KL

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    Indoor Herbs, Indirect Light? Dubious

    Dear Doyenne,
    Six months ago, we moved into a little condo in Salt Lake City, Utah. Our new place is burgeoning with opportunities -- but it has a northern exposure and no gardening space whatsoever. Are there any herbs or edible plants that can withstand the indirect light and low humidity of an indoor pot? We do have a window facing east, if it needs direct light -- but it would only get it in the morning.

    On another note... I planted a grapefruit seed two years ago to see what it would do, and it sprouted and is doing very well -- at six inches tall. Is there anything more I can do for it?



    To be honest, very few herbs can withstand the low humidity and lack of light in a house to really thrive. However, you might try chives or basil, both of which can work for a limited amount of time.

    As for the grapefruit: let it dry out between waterings. Then fertilize with a 1/2 dilution of liquid fertilizer during the summer months each time you water. And, to avoid spider mites, make sure to wipe the leaves off once or twice a month to remove dust.

    Hope this helps, KL

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    Moving Plants From State to State

    Dear Doyenne,
    I will be moving from Greenbelt, MD to Portland, OR. There are two plants in my garden to which I have an emotional attachment and simply must move with me: a Columbine originally from my grandfather's garden, and a native geranium (which I found at a local garden club sale). The columbine bloomed like crazy this year and I've saved the seeds as insurance. The geranium is small.

    What is your advice for moving these two plants? Is it legal to take them from the eastern U.S. to Oregon?


    It's not illegal to bring these plants into Oregon (California is a different story). People bring stuff in all the time. And while I strongly doubt that your columbine or your geranium are going to cause any catastrophes, I strongly suggest you wash off the roots and bring not a speck of Maryland soil.

    Believe me, that's the moderate's view. I've checked with other people who are against you bringing in the plants, period (don't worry, I didn't give them your name!). I like the idea of your bringing the columbine seeds rather than the plant itself, and I'd prefer you take rooted cuttings of the geranium rather than the mother plant. That way any risk of pest or disease will be significantly reduced if not eliminated.

    The choice, of course, is yours. But again, leave the soil home.

    Best of luck, KL

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    Big Dogs and Grass Don't Mix

    Dear Doyenne,
    I recently put some brand new Kentucky Bluegrass sod in our side yard and watered it religiously. I have three rather large dogs -- two Boxers and a Lab. After three weeks of keeping them off the sod, I finally let them go into the yard (it's fenced off especially for them). Now, the yard is full of yellow dying grass in the spots where the dogs urinated. Is there a way to bring that grass back to life?

    Thank you.

    Oh nameless, stateless one,
    High concentrations of urine (ammonia) are difficult for any plant to survive and grass is definitely not "urine-hardy." If this is the area the dogs constantly use for their toilet, the grass is going to burn. NO way around it.

    You could run out each time they pee and water the area to dilute the urine (I can tell you're not jumping at this). Otherwise, the problem is not going to go away. Your other option (just what you want to hear after slaving after the sod) is another groundcover altogether - the most dog-proof, pebbles or mulch.

    Kiss the pups for me, KL

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    Leave Them Violets Alone!

    Dear Doyenne,
    I live in north central Indiana (zone 5). I have a small invasion of violets in my lawn. I'd like to avoid using toxic chemicals if possible as I have a 14-month-old boy who loves to be outside. If I do use Roundup, how long should my child be kept off the area where I spray?

    Any advice would be greatly appreciated.

    Please don't think me rude or dismissive, but I have to ask: Why in the world would you want to rid your lawn of violets? They are so lovely, they add so much character to (boring old) grass, and they are completely harmless. Why not let them flourish? Imagine the bouquet your little boy will pick for you once he figures out how!

    Best, KL

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    Growing Ginseng

    Dear Doyenne,
    I have searched, and had no luck finding out how to raise ginseng. Can you point me in the right direction?


    Ginseng is found naturally throughout North America in hardwood stands of ash, birch,and maple and can be cultivated in the home garden under the right conditions. Seeds are readily available from a variety of sources. Check out these two interesting online sources of information on the history and cultivation of ginseng:
    The American Ginseng Manual, a complete treatise on the subject, and Growing Genetically Cross-Bred Glacial Gold Ginseng Seeds. If you do begin planting and using this remarkable plant, be sure to read up on some of the issues regarding its safe use as a dietary supplement.

    Best, KL

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