Learn to grow with the “Square Foot Gardening” method!

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    Want to grow twice as much in half the space with half the work? Mike McGrath, host of You Bet Your Garden, helps us celebrate Square Foot Gardening–the great Mel Bartholomew’s method of growing in grids and raised beds. Plus answers to all your growing questions.

    Question of the Week:

    And this week we pay tribute to one of the true giants of the organic gardening world with two ‘top ten’ lists that Mel created when he revised his classic but heavily engineering-oriented 1981 book into the much more accessible and readable “All New Square Foot Gardening” in 2005. Biggest change: Instead of the old advice of digging out a hole and filling it with a soil-free mix and compost, Mel moved up to placing raised bed frames overtop of your existing soil and filling them with his famous “Mel’s Mix”. No digging. But the grid system—square foot areas divided by strips of wood lathe—did not change one bit. To many people, the grids are Square Foot Gardening.

    Learn the 10 commandments of Square Foot Gardening »

    Highlights from show for May 14, 2016:

    Keeping dogs out the garden

    Michelle from Nashville, TN shares a common thread with Mike, as she just rescued a new Pyrenees, Russell, the same breed to which Mike was a proud owner. Michelle is having a hard time keeping Russell out of her garden. He’s constantly ripping up the soil and digging pits. Mike acknowledges that Pyranees are the best dogs in the world, but reminds us that these large dogs are known to protect, guard and warn predators. The best way to keep her new dog from the garden, says Mike, is to train him. “The dog wants to please you,” says Mike, they’re simply looking for a place to cool down and relax in the heat of the summer. The best way to do this training is to go out to one of his spots, use your hands or a shovel and start digging in one of his holes. Continue to do this week after week and soon the dog will realize that this is his dedicated spot. Reward him as he learns this, Mike adds, because that’s the best way to get a dog ten times stronger than you to learn.

    Creating healthy footpaths in your garden

    Charles from Gloucester County, NJ is helping his father with the large undertaking of starting a small organic farm. His father is currently using shredded leaves in the walkways in between his permanent beds. However, Mike advises him that this is “the worst thing he could do.” Mike warns that tilling carbonaceous materials such as wood chips, whole leaves, or shredded leaves into the garden beds can stop the breakdown of carbon and prevent the plants from getting oxygen. Additionally, the carbon will try to attract nitrogen, and in turn steal food from the plants. Tilling in the garden beds, Mike says, could prevent growth for years. Mike advises Charles and his father to first be sure he has a good bulk source of compost for his soil. He also suggests using two inches of shredded leaves with a mulch on the beds. This way, earthworms will colonize the leaf litter and their casting will help feed the plants. Never forgetting that earthworms in the garden improve productivity immensely. He could use true wood chips, as in chips from actual trees, in the walkways between the beds. Mike also encourages Charles to get in touch with NOFA NJ, which stands for the Northeast Farming Association of New Jersey. This great organization provides a support group for organic farmers, with workshops covering everything from marketing and finances to the actual crop growing.

    Mosquito control

    Hollis in Middletown Delaware is having a problem with a large number of wasps and mosquitos attracted to the shade of the evergreens in her yard. She’s currently using a chemical spray to keep them under control, but wants a more natural fix, so she’s been reading up on bat boxes. Mike tells Hollis that while bat boxes do produce great results, the only ones sold in the US are extremely large, about the size of a television set, and must be placed at least thirty feet in the air. Additionally, the idea that bats eat mosquitos is a myth created back in the 1950s; they only eat very large night-flying insects. Mike also informs Hollis that wasps do not fly at night, so a bat box would be virtually useless to her. However, he does encourage her to look into dragonflies, which are natural predators of mosquitos. In fact, there is a whole family of dragonflies known as mosquito hawks. Hollis can attract dragonflies to her yard with perches that are much simpler than bat boxes and will work much better for her. Mike also suggests buying BTI traps. BTI is a naturally occurring soil organism that can be put in standing water to attract mosquitos to lay their eggs. These eggs will not hatch and Hollis will be cutting down their population in her yard. Mike points out that the “creepy European hornets” that Hollis is so afraid of do not even have stingers and eat a ton of pest insects. In fact, these hornet pose less of a threat to her than the chemicals she is using to get rid of them. Mike suggests buying a bug vacuum to ease her nerves when it comes to these bugs.

    Tree care in a new home

    Taylor in Noble, OK just moved into a new house and is left with the remains of the former owner’s hobby for horticulture. He asks Mike about caring for two specific trees, a Dogwood in the front yard and a Magnolia in the back. Taylor was told that they needed special care, as they aren’t very common in his area of Oklahoma, but does not know what to do. Mike tells Taylor the basic rule for a Dogwood is that they need morning sun and afternoon shade. Since the Oklahoma summers are so hot with so much wind, this afternoon shade is even more important than it would be on the east coast. Taylor tells Mike that the former owner must have known what he was doing, as an Oak tree blocks the afternoon sun from hitting the Dogwood. According to Mike, there is nothing Taylor needs to do for the Dogwood. Maybe he could provide a slow drip of water around the base if there is an intense heat wave with no rain, but nothing more than that. As for the Magnolia, Taylor is worried because it didn’t flower as much as he was expecting. Mike informs him that there are many different types of Magnolias, and as the flowers are replaced with fruits at the end of the summer, he can look online and identify his type of Magnolia. With this information, he can find specific care instructions. Mike tells Taylor that as long as the leaves are nice and glossy, which they are, then the trees are healthy. There is nothing he should do for the Magnolia tree either. Mike says that the best Magnolia specimens he has ever seen were in abandoned farm houses. This reminds us, says Mike, that “we need these plants more than they need us messing around with them.”

    Neighboring chemicals

    Lisa in Northwest Missouri moved away from city-life so that she could have her own organic garden, only to learn that two of her neighbors are spraying herbicides to grow GMOs. One neighbor is using a ground spray, which Mike acknowledges is not too bad, while the other is using a crop-dusting method. Mike informs Lisa that every county has a local EPA office and she should register there and use them as a resource. He tells her that if she has enough land to put out a farm stand and maybe sell some excess produce in the summer, she should announce that as her intention, giving her more rights than just a home gardener. These farmers are not allowed to spray on a windy day, nor can they have their material drift more than a certain number of feet off their property, Mike says. Lisa should monitor the plant death outside of their fields; if the brown areas are only a foot or two outside their property, then they are doing a pretty good job. The crop-duster should focus his herbicides to the center of his fields, letting them drift to the outside instead of onto Lisa’s. However, Lisa should not be afraid to contact her local, not national, EPA office and turn them in if she sees any violations. Mike tells Lisa that she has the right to protect herself from the sprays and their drifts.


    Cheryl from Princeton Junction, NJ is an over-protective owner to a new dog. She wants a safe alternative to the harsh chemicals her husband sprayed to keep mosquitos away. She does not want to harm her dog, but she is a mosquito magnet and now cannot go outside without coating herself in DEET. Mike says that all professional companies that spray for mosquitos now have an organic option that is a bend of several highly effective botanicals such as lemon eucalyptus and catnip. These natural repellents are just as effective, but won’t harm Cheryl or her new dog. Mike tells Cheryl that though many people believe you need to reapply spray with DEET because is comes off into the air, it really goes into your blood stream and excretes through your kidneys and liver. That is why it’s so important to use these natural repellents. According to Mike, putting such a harmful chemical on your skin is crazy. He also tells Cheryl she can buy BTI at any local hardware store or home center. She can leave out this BTI in standing water, attracting the mosquitos to breed and lay their eggs, only the eggs will not hatch in the BTI. Mike encourages Cheryl to visit the garden answers section of the “You Bet Your Gardens” website and read the articles there on mosquitos if she wants to be more informed. Another alternative is to try this commercial, all-natural lemon eucalyptus repellent made by Repel, a company that also manufactures DEET products. Mike tells her to remember that these botanically based insect repellents have been proven to be just as effective as the chemically based products.

    LEDs versus fluorescent lights

    Mark from Ewing, NJ is ready to discuss with Mike the use of LEDs versus fluorescent lights. Mark, who is evidently a lighting expert, explains how fluorescent lighting is perfect for plant growth because it has an ultraviolet component of 400 nanometers, which is close to what the sun produces. This makes it perfect for plant growth within about one inch of the tubes, as Mike always says. LEDs on the other hand have almost no ultraviolet component. In fact, LEDs are used in places like art studios, where they do not want degradation cause by ultraviolet light. Mark brings this up because of Mike’s advice on another week’s show. Mike explains that he had recently made a personal appearance where he was told that people had seen “shop light” fixtures that looked like fluorescent lights but were really LEDs. As LEDs are much cheaper and last forever, he thought that this would be a great thing. This brought Mike to the question, “Is it impossible for an LED to have a UV component?” The answer: it is not impossible to create, however this product is not on the market yet. It may be coming soon though, so look out! Mark suggests testing your lights with a calculator that has a small solar disc on it. If you put this piece under the LED in an area of complete darkness, you can barely see it glow.

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