Winter Cover Crops

Cover crops offer many benefits to soils and gardens. They protect soil from the compacting and dissolving force of the rain. They provide shelter for worms who might otherwise drown in our rain soaked soils. They supply home grown organic matter, which builds humus, improves soil tilth and texture, feeds worms and micro-organisms, and supports the soil nutrient cycle.

Cover crops also protect soil fertility levels by utilizing nutrients that could be leached into sub soils and aquifers and find their way, as pollutants, into our water ways. Soil nutrients bound in living plant material is not subject to leaching. In addition, by carefully selecting the cover crops, you can improve your soils carbon and nitrogen content.

Carbon is essential to the life of soil micro-organisms and the soil nutrient cycle. It is especially useful if you have noticed that plants in your garden tend to have weak stems and trail, sprawl, or lean when they should be upright. (Weak stems can be a sign of carbon impoverished soils.) Carbon is produced in abundance by the following easy to grow cover crops: agricultural mustard, flax, fodder radish, tyfon, winter oats, rice, rye, as well as winter triticale and wheat. As soon as your summer crops are through producing, you can cut them off at ground level and rake them into a compost pile (or turn them under) and broadcast your rows or beds with the carbon crops of your choice. (Cover crops should be sown thickly. You want the plants to inter-grow to protect the soil.) The carbon that these plants provide is extracted from the air, so you can congratulate yourself on doing something small to help with the greenhouse effect and global warming! Many of these plants will also produce edible greens or seeds, in addition to improving your soil.

Agricultural mustard, fodder radish, and tyfon can all be eaten in soups or sautéed with garlic and onions for an old fashioned dish known simply as “a mess of greens.” They are good sources of beta-carotene, folic acid, and calcium. (You can improve your own health while you improve the health of your soil!) Once these cover crops go to seed, if you let them grow that long, the seed can be threshed and used to grow spicy sprouts that will enliven your spring and summer salads. These same seeds can be used to flavor pickles, cracked to make a spicy seasoning for savory breads, and ground and mixed with vinegar to make dark flavorful mustards.

Flax, oats, rice, rye, triticale, and wheat seeds are also edible. They can be used whole, in mixed grain dishes, sprouted for salads or sandwiches, or ground and used in baked goods. If you want to try eating your grain, be sure to choose those that “resists lodging” if available, and definitely avoid those prone to lodging. (Lodging is a term used to refer to the plants dropping the grain.) Also look for varieties that are hull-less or easily threshed. Don’t expect to get a lot of grain from your garden, but it is a fun experiment to try which children, and it helps everyone understand how their food is produced. Dried grain seed heads are also fabulous for crafts. They don’t need to be hull-less or easily threshed for use in flower arrangements, wreathes, and so forth, so you can choose decorative colors or long awned grains if you like.

The other option in cover crops is to focus on nitrogen fixing plants. A variety of legumes are available that pull nitrogen right out of the air. If plants in this year’s garden grew slow, seemed smaller than normal, or if the green colors seemed faded out, nitrogen fixers might be just what you need to perk your soil back up. A number of types of clover, and vetch are available for cover crops. Low growing white and red clovers can be broadcast under summer crops now, or you can wait until the beds are cleared or turned and then broadcast the seeds. The Sweet Clovers are a nice option for cleared beds, as they also produce a lot of carbon and organic matter, and will reward you with sweet smelling flowers in late winter and early spring. As they are slow growing, it is a good idea to mix them with agricultural mustard or other clovers to best protect your soil from early rains.

If you want to grow a mix of carbon and nitrogen for your garden, add some Austrian field peas to your carbon crops when you sow the seed. Austrian field peas happily inter-grow with other plants. They produce small cheerful sweet pea type flowers and their seeds can be used in soups. Another choice, bell beans, are miniature fava beans that do well in winter. These beans do not need staking or trellising. They produce both nitrogen and carbon. And like other beans, the immature pods, as well as the mature beans are edible. To best protect your soil bell beans should be inter-grown with red or white clover.

Cover crops are pretty easy, you just choose your seeds, minimally prepare your ground, and broadcast the seed fairly thickly. You can cover the seed with a sifting of compost, leaf mould, or a purchased soil amendment. If this is not practical, and you have turned your summer crops under, you can rake the seed in. For a third option , you can simply cut or mow your summer rows, and wait for the next rain. Seed broadcast while it is raining are fairly safe from marauding birds. The action of the falling water settles the seed into crevices in the soils surface, and the moisture helps it germinate quickly. Then you just let nature take its course. (Cover crops can be cut or mown during the winter to keep their height down, if you choose. But it is not necessary.) Next spring you will have to decide if you are going to let your cover crops mature for their seed, or if you will cut or turn them under as soon as you are ready to plant your spring garden. That mostly depends on how much space you have. Either way, your winter cover crop will provide you with ample material for composting and mulching. Your soil and the creatures that live in it will thank you.

Check with your local farm supply or feed store for recommendations on the varieties best suited to your area. If you would like more information visit Bountiful Gardens On-Line: http://www.bountifulgardens.org or call (707) 59-6410 to request a catalog. They have seed for all the varieties mentioned in this article, and many other choices.

That’s all for now, but stay tuned, next time we will be getting ready to grow some of the yummy giant fava beans. Until them, you can probably find me out in the garden, Digging the Dirt.

Copyright 2006 Harvest McCampbell, from my column "Digging the Dirt," published in The Hoopa Valley People Newspaper, Oct 17, 2006. Posted here with permission. http://www.hoopa-nsn.gov/enterprises/newspaper.htm

Fall Greens

Young Kale and Mustard plants sown in the fall.

Many edibles practically care for themselves during fall and winter. Cilantro, lettuce, fennel, mustard, chard, and kale, among others,  love the weather ahead. Cool moist temperatures, and lots of rain bring us sweet delicate greens for our fall and winter soups and salads. Now is the time to get these delectables growing, if you can just find the space.


Cool season greens are lovely to look at, especially as fall grows old and winter comes to visit with its cold, grey, and stormy days. Lettuce can look quite perky when the rest of the garden is bedraggled by rain. It is available in all shades of green from very pale to very deep. There are varieties with speckles, and splashes of purple or red, and other varieties that boast deep red or purple leaves. All these colors of lettuce come in a variety of leaf forms from the large simple leaves of romaine to frilly butter crunch and lacy oak leaves. No room in the garden? A few pots or containers growing lettuce will look attractive on a patio or porch!

If you have a large pot (or an empty spot in the garden or flower bed) Red Giant Mustard would make a dramatic back drop for the smaller and more delicate lettuce plants. Or if you like the red and purple lettuce types, Giant Southern Curled Mustard (also called Green Wave) with its pale green leaves would make a fitting back ground for your fall container garden. Swiss chard is another interesting plant that will eventually grow quite tall, and the newer hybrids come in a multitude of stem and leaf vein colors.

Fall sown mixed mustards growing like crazy with the longer days of spring.

 There are also many lovely types of kale, in a variety of colors and leaf shapes. While they start out small and delicate - many grow up to make large interesting plants. Look for Red Russian Kale, Red Bore, or Dinosaur Kale. The young leaves of all these plants make good additions to salads, the older leaves are great for soup, and the plants make a dramatic statement in a pot or out in the garden.


Cilantro and fennel both love cool wet weather and they will thrive in the garden or in containers on a bright porch or patio. They add flavor to winter salads and soups, as well as a delightful fragrance to the air. Their lacy leaves also add textual interest to the garden or groups of container plants.

Fragrant and tender Fennel!

There are several steps to creating an attractive fall container garden, not the least of which is collecting your containers. Folks with ample budgets can find many new decorative containers at nurseries and garden centers, as well as original pieces from galleries and antique stores. The rest of us can be content with second hand and dollar store finds or recycled items from around the house.

Empty coffee, juice, and other large cans (at least 3 inches in diameter), make great containers for growing greens. You can also cut the tops off of empty plastic containers (such as milk and juice jugs, soda and water bottles, soap and bleach containers) and use them as containers. Make sure to thoroughly wash any residues from containers that contained household supplies. You can use a hammer and nail or a can opener to make drainage holes on the bottom of cans, or a sharp knife or awl for plastic containers. (Be careful!) Next add a few rocks to improve drainage and keep your container from getting top heavy as your plants grow. Save your largest containers for giant mustards, Swiss chard, kale, or cabbage. Cabbage doesn’t get as tall as the rest, but it needs lots of room for its roots. (And it is available in a number of attractive colors and forms.)

Next you will need to supply your snazzy new containers with some potting soil. Your local nursery can make recommendations for you, or you can make your own. If you don’t have finished compost or access to leaf mould, a simple fall potting blend can be made, starting with dry leaves. You want crisp leaves that crumble into small bits when scrunched or rubbed between your hands. Old corn or squash leaves and leaves that have fallen from your trees are all possibilities. If they aren’t crisp enough yet, spread them out on a tarp or old sheet and leave them in a sunny spot. Turn or stir them once a day until they crackle and crumble when you crush them. (If rain threatens you can move them into the shed or garage until we get a sunny day.) Two parts crumbled leaves, two parts sand, and one part garden soil is a good starting recipe. If you mix up at least a gallon’s worth, you can add a handful each of used coffee grounds (for nitrogen) and wood or paper ashes (for minerals) and you are ready to get growing.

If seeds are not your thing, check out the plant starts available at nurseries and hardware stores. Many types of lettuce, kale, cabbage, and other fall greens are available right now. Simply plant them in your containers, keep them moist (but not soggy) and cool until the young plants start to grow. Once you see some new growth forming, gradually move them to the sunniest spot on your porch or patio and watch them thrive.

Fall greens are easy to start from seed. It's not too late unless your ground may freeze solid,or if you will get a heavy blanket of snow. You can plant a few seeds directly into the potting soil, according to the directions on the packets. Seeds and young seedlings will need to be kept evenly moist until they are established, and then you can enjoy their colors and fragrance, both on the patio and in the kitchen through the blustery months ahead.

Seeds are available at many hardware, health food, and grocery stores. If you don’t find what you are hoping for, check out Territorial Seed: http://www.teritorialseed.com (800) 626-0866. They have a nice selection of lettuce, spinach, chard, mustard, and cabbage varieties, and they have fennel, cilantro (listed under coriander), as well as a mixed packet of colorful kales that I would love to try.

If you are searching for seeds on a budget, don’t forget to check with friends, relatives, and neighbors who garden. Many people save their own seed, and others are unable to use all they purchase. Gardeners are usually happy to share when they have more than they need. And you might just make their day by asking. Most gardeners love to show off their gardens and share their tips to success.



Copyright 2006 Harvest McCampbell, from my column "Digging the Dirt," published in The Hoopa Valley People Newspaper, Nov. 10, 2006. Posted here with permission. http://www.hoopa-nsn.gov/enterprises/newspaper.htm

Edited and photos added, 11.13.2016.  Copyright Harvest McCampbell.  Please feel free to share via the buttons below.  All other rights reserved.

Companion Planting

Not all that long ago, companion planting was looked on as a sort of a fringe ‘science,’ more related to moon worshipers than to serious gardeners. When I first heard about the practice I was in my early 20’s and it greatly appealed to me. The basic premise of companion planting is that some plants actually like to be near each other, while at the same time, there are plants that actually despair in each other’s company. The idea of plants having a soul, of liking and disliking each other, even at the species level appealed to my young sense of idealism.

Companion planting arose out of ancient and on going observations that clearly pointed to some plants doing better (or worse) when growing in the presence of certain other plants. Perhaps it is anthropomorphism to describe these affinities as likes and dislikes, but we humans tend to describe almost everything from our own perspectives. So here ya go: In this view carrots are said to like onions and peas. While potatoes are said to dislike sunflowers and walnuts. Perhaps you have noticed that some of your plants like or dislike being too close to your favorite shrubs or trees. There are actually some explanations that serious gardeners can understand.

While some of the more mysterious effects plants have on each other occur on a molecular level down in the root zone, a lot of it starts in the leaves. Plants absorb carbon dioxide through their leaves, and depending on the species, to a greater or lesser extent they can also absorb nitrogen, sulfur, and other compounds right out of the air. These compounds are used to for the plants life processes, to form vitamins, phytochemicals, essential oils, anti-oxidants, etc. Any absorbed compounds in excess of what the plant needs are sent through the plants vascular system down into the roots. Here is where the real magic begins to happen.

Plant roots secrete a very subtle, moist, jell like substance, a few millimeters into the surrounding soil. Through this substance they exert a profound effect on soil chemistry. This jell is rich in plant produced compounds, and one of its chief roles is to nourish soil micro-organisms that fuel the soil nutrient cycle. It is in this zone that the cation and ion exchanges between the roots, soil organisms, and mineral and humus particles are unfolding. The plants exchange excess carbon, oxygen, and other compounds they have absorbed through the air, or that they have stored in their tissues - for soil and humus bound nutrients that are necessary for their lives. They are also capable of secreting their own home made chemicals that effect the plants growing around them. And they definitely do this, some of them all the time, and some only if the need arises.

Lets imagine a place, like Hoopa, where day time temperatures and night time temperatures can be as much as 50 degrees different, and are often as much as 30 degrees different. This temperature difference is pretty hard on many plants. Plants vascular functions are tied to something called the evapo-transpiration rate. This is fueled by air temperature, and our large temperature differences cause an extra stress on plants. This can create a situation where plants may need more soil borne essential nutrients than is commonly expected.

Now, lets continue to imagine these plants are growing in a place, like Hoopa, where the rain fall is often over 30 inches a year. Perhaps they are growing out there in our yards right now, after a very wet year of nearly 60 inches of rain. As we discussed in a previous article, when rain fall is up, soil nutrient levels can be down. (The cure is organic matter – but it is not a quick fix.) What on earth is a poor plant to do. He can’t move to a different neighborhood, so he endeavors to change the neighborhood.

Some plants have adapted to survive rigorous conditions by either improving conditions for the entire plant community or by attacking the rest of the plant community. They do this, in part, by the chemicals they exude from their roots. These chemicals can improve the bio-availability of soil minerals, or they can inhibit germination of seed, inhibit growth of neighboring plants, or in extreme cases, they can be down right toxic to the plants growing near them. (These selfish plants want to keep all the soil nutrients for themselves.) While science can explain the generalities, it can’t explain what is going on out there in your garden. Because it is all too complex and variable.

What chemicals a plant will produce and exude and how adaptable the surrounding plants are is dependant on a myriad of things that change from time to time and place to place, even inside a single garden. So what’s a gardener to do? First and foremost, trust your own observations. If you have plants that get along just fine, while a book or magazine article claims they don’t, ignore the article. What they are saying may be true in a different soil or climate – but if it works in your garden, who cares.

If on the other hand your petunias (for instance) won’t grow for nothing, but your neighbor’s petunias thrive, look around to see if you might have shrubs or plants that could be inhibiting growth. Look for something growing near your petunias that isn’t found in your neighbors yards. And then adapt. Try planting your petunias far away from your sunflowers, corn, or walnut trees, for instance. Or grow them in raised beds or containers. If all else fails, just claim you are a moon worshiper and don’t have the petunia mojo and grow four o’clocks instead.

Some plants are so good at making growth inhibiting chemicals that they not only exude them from their roots, the exude them from their leaves, they permeate the very tissue of their stalks and branches, and upon decomposition of those leaves the chemicals permeate the soil. However, for every plant that specializes in poisoning other plants, there are a dozen that specialize in thriving anyway. By your own observations and experimentation you will discover which plants make the best companions for the specimens in your own garden, and that is knowledge you can pass down.

In the mean time, when you hear long time local gardeners talking about plants that like or don’t like each other, pay attention. That is the companion planting advice that is most likely to hold true in your gardens. You can smile in reply and say “Yes, it is all because of some magical stuff that happens way down in the dirt.”

For more information ask your book store or librarian to recommend some titles or see: Soul of the Soil, by Grace Gershuny (Chelsea Green Publishing), and Designing and Maintaining Your Edible Landscape Naturally by Robert Kourik (Metamorphic Press).

Stay tuned, next time we will be getting ready to plant our fall greens. Meanwhile, you can probably find me out in the garden, Digging the Dirt.

Copyright 2006 Harvest McCampbell, from my column "Digging the Dirt," published in The Hoopa Valley People Newspaper, Sept. 26, 2006. Posted here with permission. http://www.hoopa-nsn.gov/enterprises/newspaper.htm