Get Started: Cover Crops

 

What if I told you that you might still have time to plant a beneficial crop this year? It sounds crazy with the leaves falling as fast as the temperature. It seems like there's not enough time to get anything going other than spring blooming flowers or garlic for next summer. 

Well, I present to you today a crop that only needs 15-30 days to germinate and grow before the snow comes and can be "harvested" as soon as the ground thaws! We're talking about "Cover Crops." 

By this point in the year, you are probably in the process of tearing out your spent garden annuals. Tomatoes are pretty much shot, summer squash is done-for, and you better believe your sweetcorn has been harvested, unless you're doing a corn maze for Halloween! So now you leave your garden bed empty and bare until spring, right? I suppose you could, and I know I have, but why not fill it with 'green manure' instead? Cover crops are an off-season crop that have tons of benefits, including fertilizing your bed for next year! 

Cover crops are not meant to be harvested for food, but rather, their purpose is to be tilled under to make room for your cash crops. By planting a cover crop between harvest and planting, you can reduce erosion, choke out weeds, limit soil compaction, and most importantly, return nitrogen to the soil. This last bit is the main focus today, and it depends on what you actually plant.

Legumes!!!!

There is a magical family of plants called "legumes." You know legumes, right? The first thing I think of is beans. Kidney beans, string beans, black beans, fava beans. Peas are also in this group. There are some others too that may surprise you. Alfalfa, which I know primarily as a crop that is made into hay, is a legume. Similarly, soy is as well. I know, it's a bean and should be obvious, but when I think of soy, I think of endless fields of green just like the alfalfa plots around us.

Here's another surprise: clover is a legume. This one I learned today honestly. I knew it had the same properties as beans when it came to cover crops, so it makes a lot of sense now as it is related.

What makes these plants so special though? It can't be the fruit of the plant that makes the ground better, can it? Clover doesn't produce a pod like beans and peas, and 15 days surely isn't enough time to even get them to produce. You see, legumes have a special interaction with a group of bacteria called rhizobia. Let me take you underground for a moment:

The roots of leguminous plants form these nodules as they enter a symbiosis with rhizobia bacteria. The plant pulls nitrogen out of the air during photosynthesis and the bacteria convert it into useful compounds in the soil. Because of this, we can replace much-needed nutrients in the ground after other crops had just removed them. This is why soy is often used in crop rotation with corn. Corn takes a heavy toll on the soil and by planting soy for a season, farmers can drastically improve crop quality the next year.

What cover crops do is a miniature form of crop rotation. Rather than planting a whole season, we allow the crop to become established just as winter hits. By tilling it under in the spring, we prevent the crop from expending any energy toward growing fruit, and its entire life is utilized to push nitrogen into its roots. 

What should we plant? Well here at Third-Acre, we have a special relationship with clover. It's what really got us started with our anti-grass mindset, so we always have clover seed available. It germinates quickly, takes very little care, and does a lot of work fixing the soil. We also will add beans and peas too. Any are really fine. Sometimes we use culinary beans from the store, or peas left on the vine from summer. Other good options are alfalfa, hairy vetch, and soy. 

You can plant other cultivars in your cover crop too. Deep-rooted vegetables are good for soil compaction and pulling nutrients up. A long variety of radish is great as they germinate incredibly quickly. Winter wheat is good as well. Now for those of you who are into deer hunting, this shopping list may sound familiar. Most of these plants are included in food plot mixes! In fact, buying a five-pound bag of food plot mix may be more economical than piece-mealing this together.

Now given, it is better to get this started as early as possible. September is good, but for clover and radish, you don't need 4 weeks to grow it up. As long as it is germinating, it is beneficial. 

Once the ground thaws and you are ready to start planting, just go ahead and till the bed as you normally would. Although the main draw of the cover crop is the nitrogen-fixing roots, direct-composting the plants into the ground will give nitrogen back as well!

Have fun with this! I love seeing the green beds in October and November. It helps ease me into the dreary season that is Michigan winter,