Sunn Hemp


Veg Hill is between 1/4 and 1/3 of an acre. When you farm the Amanda way, sitting in the dirt pulling weeds by hand, that’s a LOT of real estate.


I figured that out a few days before the Farmer-in-Chief, and I persuaded her to limit her growing this summer to the six western rows, leaving the six rows on the east for cover crop. Last Monday we had a chance to plant that cover crop.

When we attended Southern SAWG, I heard a great presentation from Jeff Moyer, the Farm Director of Rodale Institute. He said something that has stuck with me: if you’re serious about organic farming, you should be paying just as much attention to your cover crop as you do to your target crop. How many of us can say we do that? I know we sure can’t.

For our cover crop this summer, we chose sunn hemp, a relatively unknown and little used cover crop in the U.S. For us, it seemed the ideal choice because of three important factors. First, it’s renowned for its tap root that can break up hard soil. That’s a real blessing on Veg Hill, which tends toward the impenetrable. Second, it’s a nitrogen fixer, and you can hardly go wrong adding a little more natural nitrogen to your soil. Third, sunn hemp can grow to four feet within 60 days and up to six feet in 90. That’s a lot of biomass, and when you’re farming organically, biomass is where it’s at for keeping soil strong and fertile.

Amanda used her Earthway seeder to plant the sunn hemp seed. We tried to keep the rows straight but failed miserably, because we had no visual cues other than a flag at each end of the row. That same afternoon, however, we installed the drip tape, which of course straightens up the line naturally.The sunn hemp had germinated, and we had visible green shoots, within two days of planting!

We will get out soon (perhaps later today as my Father’s Day gift) and supplement the spots where the seeder got so far off the line that the drip tape is not helping the sunn hemp to come up.

Amanda’s plan is to use row 6 (the last row containing sunn hemp) for her fall garden, and we’re thinking she will plant it around the middle of August. So one row will get only 60 days of growing time. The rest we intend to let grow a full 90 days.

In each case, when it’s time to bring it down, our plan is to use a crimper. Big agricultural operations use a heavy roller on a tractor, bristling with blades that cut the crop every eight inches or so and force it to lay down. We will use the same principle, but as in everything else we do, on a smaller scale. My plan now (Amanda is skeptical) is a sharp-edged angle iron, screwed to a treated 2 x 6 board with ropes at each end. You slowly move down the line, repeatedly stepping on the board and crimping the stem of the sunn hemp. We have a couple of months during which I can fashion my new toy. My covenant is that I will post video here if and when I can get it to work.

The video runs less than a minute; it shows the Earthway seeder in action and gives you an sneak peek at how the sunn hemp is going to look.

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