Using perlite to amend your soil


    Mike explains the right soil mix for a Florida garden, how to make the dream of growing your own tea a reality, what plants will spruce up a small pond, how to cultivate currants and gooseberries, the process of building a raised bed for cold weather greens, how to encourage a bird of paradise to bloom and using perlite to amend your soil.

    Question of the Week:

    “Dear Mr. McGrath: My wife is an avid listener of your program, planning her Saturdays so that she can be home when your show is on. She suggested that I contact you with my small concern that the perlite you often recommend isn’t ‘organic’ in any sense that I recognize as a chemist. Or probably in any sense that non-scientists use ‘organic,’ as it is a form of glass: Now that doesn’t take away from it being a useful component for gardening as you have advised; the advice is still fine. I would just suggest adjusting your justification of ‘it’s organic.’ Oh, and rest assured that I am also a listener who enjoys your show. Keep up the good work!”

    — Harry from Havertown, Pennsylvania

    Learn what perlite is and why it IS organic »

    Highlights from show for January 18, 2014:

    The right soil mix for a Florida garden

    In sunny Florida the gardening season starts early. Tana, from Daytona Beach, wants to plant her new raised bed garden right away, but her homemade compost isn’t ready yet. She consults Mike on the best soil mix to get her garden off to a good start. Mike suggests that Tana take advantage of the local availability of free sand to offset her costs and ensure that her bed has good drainage. Mike explains that a mix of equal parts sand, organic soil, and high-quality compost will yield the best results. “It sounds like, especially in your climate … that you’ll be making reliable amounts of compost in the future. So for this one bed that you’re anxious to get started, I would say spring for a couple of bags of good-quality compost to put on top … every time it rains it will be like a little dose of compost tea down to the base of your plants.”

    Making the dream of growing your own tea a reality

    Chris from Hendersonville, Tennessee wants to grow his own tea, but he’s encountered some obstacles. He planted camellia sinensis plants this fall only to hear from the nursery a few weeks later that they were infested with broad mites. Chris asks Mike about how to tackle this problem organically. When Mike learns that the nursery is going to replace Chris’s plants free-of-charge, he suggests two options for battling the broad mites: “My first thought is to tear them up and burn them and start fresh next season. If you don’t want to do that and you know that replacement plants are on the way … you can’t lose. … I would spray them with the refined, plant-based horticultural oils … I would soak them now to kill the overwintering pests.” Mike advises Chris to keep his replacement plants in pots for the first season to prevent the mites from spreading and encourages Chris to keep trying: “Call us back in five years if you wind up drinking your own tea!”

    Plants to spruce up a small pond

    Peter from Little Rock, Arkansas consults Mike about water-loving plants for a muddy pond. Peter’s brother just installed a small pond for the benefit of his bull and chickens. First, Mike reminds Peter that standing ponds breed mosquitoes and suggests that he install a fountain to circulate the water or treat the water with BTI “mosquito dunks.” Mike agrees that plants are a fantastic way to eliminate the pond’s muddiness and suggests that Peter discuss this with his local nurseries to find a solution that’s best for the climate and the livestock: “So you’re going to plant inside the pond, outside the pond, and every one of those plants is going to help keep that water from becoming muddy looking to begin with … But don’t forget about those mosquitoes!”

    Cultivating currants and gooseberries

    Heather recently purchased small farm in South East Minnesota. She wants to grow hardy currants and gooseberries for the commercial market, but she is concerned that the beautiful white pines on her property might infect her plants with white pine blister rust. Mike explains that over-blown fears about this disease have obscured the fact that white pine blister rust only infects European Blackcurrants and is harmless to other varieties. Mike recommends that Heather consult Lee Reich’s book, Uncommon Fruits for Every Garden, to explore the many kinds of berries that will thrive on her property: “You can grow red currants, you can grow white currants, you can grow pink currants, and you can grow a currant that is called the clove currant which is a native American plant as well.”

    “You can grow red currants, you can grow white currants, you can grow pink currants, and you can grow a currant that is called the clove currant which is a native American plant as well.”

    Mike McGrath

    • Growing currants

    Building a raised bed for cold weather greens

    Virginia from Bensalem, Pennsylvania wants to build a raised bed garden, and she is consulting Mike for advice on the location and materials. When Mike learns that Virginia is interested in growing greens, like broccoli, kale, and lettuce, he explains that she can cultivate these plants in cold weather using row covers. But Mike is concerned that the four-to-five hours of sun her ideal garden location gets each day might not be enough for these greens: “One of the issues with growing greens in low light-levels is that they have a tendency to take up excessive amounts of nitrates, which makes them less healthy than greens that got like six-to-eight hours of sun.” Luckily, Virginia’s garden gets more sun in the winter when the trees are bare and she can begin to plant her greens as early as February if she uses a row cover.

    Encouraging a bird of paradise to bloom

    Fernando from Lafayette, Louisiana planted his bird of paradise six years ago and it has never bloomed. He is looking for advice on how to make his otherwise healthy plant produce beautiful flowers. Mike explains that bird of paradise plants can take a long time to bloom and Fernando is most likely due for his first flowers this autumn. Mike’s own bird of paradise plants have only bloomed a few times! But Mike is also concerned about the effects of the cold winter weather and the that the chemical salts Fernando has been using to fertilize the plant. Mike advises Fernando to take extra special care of his plant this spring: “I want you to remove any winter damage … Put some compost around the base. No more chemical fertilizer whatsoever and keep your eyes open for that flower spike.”

    — This week’s post was written by Marissa Nicosia, You Bet Your Garden intern

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