Fall Cover Crops
Contributed by Cris Roberts
Trask River High School (TRHS) staffed and owned by Tillamook School District 9 (TSD9) is housed on the physical compound of the Tillamook Youth Correctional Facility (TYCF) site South of Tillamook on County Port property. As part of the greater Oregon Youth Authority (OYA) system, they house and offer rehabilitation opportunities for legally offending youth ages 14-21. The Camp Tillamook Youth Transitional Facility (known as Camp Tillamook) is also housed on this same site for youth preparing to transition back into society.
In 2011, the Tillamook County Master Gardener Association (TCMGA) was contacted by TYCF seeking help to refurbish an existing, but sorely dilapidated, garden compound on its property in order to give youth horticultural opportunities. With that first project, TCMGA volunteers have worked consistently over the years to educate and guide the youth at OYA through classroom instruction resulting in many of the students earning OSU Home Horticulture certificates and with hands on guidance in the facility gardens.
While the photo to the left may appear to be a thriving, summertime Tillamook garden bed, it is actually one of our Trask River Agriculture Program (T.R.A.P.) winter “Cover Crops” planted late in the Fall on the Oregon Youth Authority facility grounds here in Tillamook. This particular one is called, “Fall Mix” and is sold by Territorial Seed Company.
There are many reasons to consider growing cover crops: They help to keep the garden-bed soil from eroding. They also replenish Nitrogen in the soil and help to hold weeds at bay. In my experience, Cover Crops also provide a wonderful visual field of green during the bleakest time of the year AND provide excellent early pollinator food come Spring (if not plowed under). An on-line site called the “Organic Growers School” has this to say:
A cover crop is a crop you grow for the soil, instead of for your plate. The practice of growing specific crops just for fertilizing and building the soil dates back to the Roman Empire. Cover crops add organic matter to the soil, and add nitrogen in a slow-release way that plants can handle, leading to less nitrogen volatilization (read: waste!). Cover crops can also act as mulches if managed correctly, improve soil physical properties in just one growing season, and attract beneficial insects and pollinators to your garden. They are also beautiful! (Organic Growers School).
I am a strong proponent of nitrogen-fixing crops, but one of the most rewarding aspects of growing Cover Crops in the Oregon Youth Authority garden has been to see that visual aspect I mentioned above of how they provide so well for our early pollinators. Knowing that our planning for our trusty, hardy and much-valued beneficial insects begins each fall, we get a wonderful feeling of participating intentionally in nature’s health and well-being.
Territorial Seed Company’s Fall Mix (mentioned above) – One of the wonderful things about this mix is that you get a variety of blended greens and, if one punks out on you, there are always others to hold the ground. It contains a blend of Austrian Field Peas, Crimson Clover, Hairy Vetch, Annual Rye and Winter Rye. One pound of this mix will run about $9.00, enough to cover 400-500 square feet of garden bed. It is my experience that this mix does well in our Tillamook climate. This cover crop fills in nicely and, therefore, looks like a full crop early on in the season. It is also a good educational tool for taking a look at several types of individual cover crop plants.
In our particular garden, the winter cover crops we have grown have included the following:
One of the magical things about this legume is that it tends to grow, then stop, then grow, then stop until our weather begins to warm in the Spring. This makes it a fun plant to watch. I also LOVE the look of Fava Bean blossoms. They have a robust white and black appearance, rather unique in a typical early-spring garden. Fava Beans can grow tall. The ones we have grown in our garden (Vicia faba) have gotten taller than some of my vigorous 6-foot youth.
Trifolium incarnatum has got to be one of my favorites! Again, in our OYA plot of ground, this crop fills in nicely as the weather begins to warm. If left to bloom, oh my! Gorgeous, bright-pink blooms catch any eye that happens upon them, including, once again, the pollinators. You may have seen this crop growing just East of the Coastal Mountain range outside Portland or Salem. Stunning.
We have grown this Clover (Trifolium alexandrinum) several times in our garden, but we can’t seem to get it to cover as well as the Crimson Clover. I am wondering if we aren’t starting the crop soon enough in the summer to get good coverage by winter. The blooms, which are creamy-looking, are pretty but not as splashy as Crimson. I’ve often thought it would be a fun visual experiment to alternate the white, pink, white, pink throughout our garden. We just might have to try that this next year.
Although often used as a cover crop in our area, we haven’t tried growing this at OYA. I do have some experience growing it in an Oceanside vegetable/fruit garden. It covered well, but also self-seeded well the following year! Buyer beware.
This plant gets a very bad rap…for probably good reasons. Once it is planted, it is hard to get rid of. The seeds tend to lurk in the soil just waiting for a chance to spring forth and concur! Mustard, however, is just beautiful! The brilliant, yellow blossoms make even the worst of cloudy days good. That is, unless, you are trying to get rid of it! A couple years ago, I had the opportunity to take a gorgeous drive to Silverton, Oregon to visit one of my favorite cousins. It was early summer and around every bend and corner the bright yellow blooms signaled abundant life. It had been deliberately planted as a cover crop. Another drive through the Palouse Country of Washington exhibited an absolutely stunning pallet of visual color. I have noticed a more tropical legume in the Territorial Seed catalog called, “Sunn Hemp” (not related to Cannabis). Crotalaria juncea seems to bear a slight resemblance, at least in color, to Mustard. I have ZERO experience, however, with this Cover Crop.
Certain Cover Crops can (and should) be grown in the summer. One that I love to grow at work is Buckwheat (Fagopyrum esculentum). I love the shy way this plant grows. It starts out subtle then, all of a sudden, makes itself known with broad, floppy, dark-green leaves and delicate, white blossoms blowing in the breeze. If left to seed, the seed heads are like little triangular purses and can be ground into flour, if one is so inclined. My favorite fact about this plant (and it has proved out in our garden) is that it is one of the favorite sources of nectar for some of our busy, prolific hoverflies. Did you know that hoverflies are avid pollinators often outcompeting the European Honey Bees? Amazing and a good reason for us to take note. These little guys, also, are native to our area! Some feed on aphids as well and some feed off of the honeydew from aphids.
That exhausts my personal experience with Cover Crops, but I hope you get bitten by the Cover Crop bug as I have and try out some of these yourself. We have many ways of contributing to the health of our precious planet. Although this is just one, it is a very fun, interesting and rewarding one.