The second method I experimented with for soil improvement/weed suppression is cover cropping.
Method 2: Cover Cropping! Exclamation Point!
Cover cropping is a fancy way of saying: planting something in an area and then later digging it into the soil to improve it. Cover crops add organic matter to the soil, they prevent erosion (not a concern in raised beds, ha), their roots help loosen compacted soil, they suppress weeds, and in this case, the alfalfa I planted also fixes nitrogen from the air and puts it in the ground where other plants can use it. Sounds pretty good, right? Cover cropping is for winners!
Well, as you can see, it also LOOKS AWESOME. Not sloppy or like a trash-heap at all.
In this case, I just did a smaller area of the bed with alfalfa, because there’s some other stuff growing there already. The lighter green plant in the top right is an arctic kiwi, and the row of gross-looking chewed up sticks along the bottom of the bed are my Jerusalem Artichokes, not yet begun to sprout this spring. So it’s only the remaining empty area of the bed that got cover-cropped.
I planted this alfalfa last year (seed from Apache seed – they sell it in bulk, it’s cheap) and didn’t do anything about it in the fall, just left it. In the Spring it grew back rather impressively, so I dug it in yesterday, following the instructions in this YouTube video. (It might seem like common sense, but I was weirdly nervous about doing it wrong. I might get arrested. By the Cover Crop Cops.)
Action shot! Dig dig dig. Also as I was taking these pictures, it rained on my phone, and then I dropped it on the ground.
All done! Like an alfalfa graveyard. The best way to do garden labour is with a photo-montage. I highly recommend it.
Also visible in this picture: the perfect tool for the job, a tool from Lee Valley called a “transplanter” that has a good sharp, flat edge for slicing through alfalfa. And danger. I got this as a Christmas gift last year and my parents even kind of wrapped it. It was quite a feat. I shall call it The Transplantor instead because that sounds more badass.
I added composted manure and worm compost to THIS bed, too. For science.
- This definitely did loosen the soil, but I think that’s more because of my aggressive poking with The Transplantor rather than the actual cover croppage itself.
- There were surprisingly few weeds in this bed, so I’d say it worked pretty well on that front, too.
- Cover cropping will make you feel like a god. You create life, and you destroy it. Whether that’s good depends on how you feel about power. For me, it was like 90% power-drunk, 10% guilty for destroying the little alfalfas.
Although little effort was required for either method (cover cropping and solarizing), both beds were out of commission for a whole growing year, which could be pretty annoying if you’re short on space. In terms of comparison, the real test of these two methods will be in the growing season to come, as I actually plant some stuff in these beds and see if there’s any improvement over previous years. I will continue my science, dear Reader. For you. And for the advancement of the humans over the weeds.
More information: Mother Earth News – Cover Crop