To use ash or not to use ash, that is the question!


    This time of year many wood stove owners are looking to recycle their ashes. Mike McGrath answers a listener’s question about using ash to kill clover in groundcovers. Plus a bit about Bio Char; and your fabulous phone calls!

    Question of the Week

    “Can hardwood charcoal from a wood-burning stove be used the same as ashes? I would like to use the chunks I sift out to help the 4000 square feet of groundcover surrounding my driveway overcome clover. I’m hoping the alkalinity (if charcoal is alkaline) will abort the clover and allow the Dianthus and Periwinkle and Phlox to prosper.”

    Ted in Downingtown, PA

    Learn about recycling your ashes »

    Highlights from show for January 17, 2015:

    Composting grain

    Benjamin from Camden, New Jersey, just across the bridge, calls to ask us a question that relates to his work in Cooper River Distillers, where they distill rye whiskey. He says that during the distilling process, there is about 200 pounds of grains that are left over, and would it be possible to compost them? Mike talks about how he has encountered that as well, that his hometown has also had a resurgence of breweries and distilleries, and what they would do in Emmaus, PA is give it to the farmers, since it makes for some very high quality animal feed. Benjamin then also asked that since it has a very low pH (~4.1 to ~3.9) if it’s safe for the pigs to keep eating it. To which Mike responds that this pH would be ideal for growing blueberries! For more information about industrial food composting, Mike recommends his friend’s website

    Gnats in your houseplants

    Trisha from Buck’s Country, Pennsylvania, has a question about gnats in the office where she works. They have an infestation of gnats living in houseplants. Mike tells her they are fungus gnats, that breed in the soil of the houseplants. They breed in the soil, which is moist and presents ideal conditions. Mike recommends BTI granules to kill all the young gnats, although the adults will remain. However, that also shouldn’t be a problem because the adult generation won’t be able to lay their eggs, and would then die off.

    Grape leaf hoppers

    Eric in Spokane, Washington had a question about his grape vines. A treasured place to sit and relax under, he is worried that the fact that the leaves are yellowing and falling earlier in the season and that they discovered some bugs might spell destruction for their tree! Mike reassures him that it is relatively easy to protect grape leaves, and that the white bug Eric mentioned, the grape leaf hopper, could also be taken care of. When asked if he had done anything different in the garden, Eric mentioned that they have been killing off a large number of wasps. That’s worrisome. Mike tells Eric, “You’ve killed all the cops in your city, and now you’re complaining that your house is getting broken into all the time!”. Mike tells him that he fears that Eric might have been what killing what had been keeping his tree safe, and if the wasps come back, that he should not kill the wasps.

    Growing a citronella plant indoors

    Nefertina from West Philadelphia, has a citronella plant that she usually has outside to control the mosquitoes, but when the weather got too cold, she brought it inside. It is growing too big, and she wanted to cut some pieces of it so that she could spread it out. However, she does not want to do that when it is winter, and it is inside the house, since she does not want it to die before it is time for it go back outside. Mike begins by first explaining to her that the real citronella plant grows in the tropics, while the plant she has is more likely to be a scented geranium. He also goes into the fact that there is no such thing as a mosquito repellent that simply operates as a potted plant; a mosquito repellent works much like any other skin protector. You need to cut it, crush it with your hands, and rub it over your exposed skin. After some questions, Mike uncovers that this citronella plant, as sold to Nefertina, is a scented geranium masquerading as a citronella plant. Mike says that getting a bag of seed-starting mix, potting soil or soil-free mix, and by using some compost, snip off the four or five of the newest leaves (remembering to put the soil in a pot with good drainage holes!)

    • Photo by Flickr user Fiona

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