A few weeks ago I got an email with the following subject line: APD Volunteers Needed!
I was scratching my head. Anyone who has spent time in Kutztown knows that APD is the Airport Diner – the only all-night eatery in that corner of Berks County. (I never could understand why the Airport Diner was referred to as the APD and not just the AD … but then I’m not Kutztown-born.) But when the kids and exchange kids thought they were old enough to go carousing at night without telling Momma, the APD was on my rounds, yes, in my pajamas, to check that they were safe.
The email was puzzling, though, because it had Centre County origins. Turns out that APD in these parts means Ag Progress Days. So last week, I volunteered at Penn State’s Russell E. Larson Agricultural Research Center at Rock Springs, location of APD, for PASA (Pennsylvania Association for Sustainable Agriculture), PCO (Pennsylvania Certified Organic), Penn State Pesticide Education, and Penn State Potatoes. Lots of Ps.
I was in my element, rubbing calloused elbows with farmers and gardeners, chatting about pollinators, and sipping on Pennsylvania maple milkshakes. I was supposed to be there as a volunteer to teach and explain, but as often happens, I finished the three days with a learning high.
At the Penn State Potato plot, I learned about a wonderfully simple technique that I have to share with all of you gardeners out there. I’ve grown cover crops and I’ve tried to steer clear of fungicides (chemicals used to reduce fungal diseases), but it wasn’t until last week that I learned about biofumigants – plants that naturally fumigate the soil, suppressing harmful nematodes and diseases.
In the last several years, potato experts in Maine, Michigan and good old Penn State have been studying the effects of growing a mustard seed mix the year before planting potatoes, and they’ve found that when chopped up and mixed into the soil, mustard greens release gases that can suppress harmful nematodes, insects, weeds, bacteria and fungi in the soil. And, at the same time, mustards serve as a green manure, enriching the soil with nitrogen and thus improving potato yield by as much as 8 percent.
It turns out that the disease suppression of Oriental mustards or Brassicas is associated with the amount of glucosinolates in the tissue of the plants. (These are also the compounds which create the hot taste of mustard). Mustards are native to the Mediterranean and were domesticated about 4,000 years ago as a source of oil, spice, and medicines. Today, researchers using these mustard seed mixes are finding that the naturally occurring biofumigant properties of mustard are only part of the story. Mustards also improve soil structure and fertility, reduce erosion, stimulate growth of beneficial microbes, draw in dozens of bees and butterflies, and, for you poets out there, they’re beautiful!
If you have an area in your garden that you are having trouble with, or were planning to let go fallow for a season, this is where you plant your mustard cover crop. Penn State plants it after a wheat rotation, cuts it just after Ag Progress Days, turns it into the soil, and then plants potatoes in that spot the following spring. I also think it would be a great cover crop after harvesting garlic in early July. It could also be grown in the fall, but I think we’ve missed the planting window for this year.
1. So, for next year, order Caliente199 from Rupp Vegetable Seeds or anywhere else you can find it. Caliente 199 mustard seed mix produces the highest amount of biofumigant gas when chopped. (3 oz. seed packet covers about 850 square feet.)
2. The tiny seeds germinate rapidly, in 5 to 10 days after planting, and will germinate in soil temperatures as low as 40 degrees. In four to five weeks the plants will completely cover the ground, and soon will produce flower buds, with yellow flowers bursting forth a week later.
3. At maturity, the plants will be three to four feet tall, with deep taproots.
4. The biofumigation properties of mustard residues are highest if plants are mowed or cut into small pieces and rototilled into moist soil around the time of full flowering.
5. Smile, knowing you did something good for your soil, your garden, and the planet. And give a nod to Mother Nature, who, it seems, thought of everything.
Here’s to your field of dreams! Laurie Lynch