published: February 2017

Garden Guru: Selecting for nutrients

by Matie Belle Lakish

Seed catalogs are piling up and the days are beginning to lengthen. It’s time to make some tough decisions about how to use that precious garden space.  Some of us may be looking at recent social and political changes and deciding that we want to become more food self-sufficient.

Most gardeners have limitations to consider. It may be time, or fenced-in area or greenhouse space, or financial constraints, or water, fertile soil, or pests, or likely, a combination of the above. For whatever reason, we make choices about what to plant, and how much of each precious commodity to give to each type of plant. How can we get more from our gardens?

A number of strategies have been used by gardeners to increase yields. Among them, of course, are traditional strategies such as growing two crops in a year by planting an early crop and following it with a late summer crop. In our short growing season this is not always effective.  Inter-planting is another strategy. I like to plant radishes with the carrots, both to mark the rows of slow-germinating carrots with the faster radishes, but because I can harvest the radishes early just as the carrots are needing more space to fill out their roots. Early spring greens can often be inter-planted with root crops such as beets and parsnips. When the greens are finished, the beet tops can grow and fill out their roots.

Another well-known strategy is to increase food and water to the plant to encourage faster and more vigorous growth. This is a strategy used by many commercial farmers, and has led to the overuse of commercial fertilizers. However, achieving optimum growth of each plant is certainly a winning strategy, even if you are growing organically, and soil health and fertility is a major factor that has been addressed in previous articles.

A third strategy is to choose plants that deliver the most nutrient density. In other words, plant more nutritious fruits and vegetables. There is a small revolution going on in the food world. It is not the genetic modification movement, but the research into micro-nutrients and their effects on human health. I reported on some of this research with the Brassica family in the November issue. The Lycopene content of tomatoes has received some press for its powerful antioxidant action in the body. The Lutein and Zeaxanthin content of leafy greens such as kale and spinach may well protect our eyes from cataracts and macular degeneration. Beet roots provide glycine betaine which offers protection against harmful homocysteine levels, helping to prevent heart disease, as well as good amounts of folate, which has been demonstrated to improve cardiovascular, neural, and psycho-emotional health.

I plan to go into more detail on some of these health advantages in future articles, but the point is that each vegetable in our garden has something to offer to our good health, but some may be real powerhouses of nutrition.

Please take a look at the chart of nutritional values for some of our commonly grown vegetables. I developed the chart based on some of the vegetables that are easily grown in our area, and took the information from the USDA Composition of Foods charts found on the USDA website. All values are for 100 grams, or about ½ cup, of densely packed raw vegetables. The values are averages, and can vary considerably depending on the nutrition of the soil and other factors related to the growth of the vegetable. However, the values for some plants stand out.

Notice the high values for kale and parsley. Kale has gotten a lot of press lately for its superior nutrition, but parsley is rarely at the top of anyone’s garden favorites’ list. Usually it is relegated to the side of the plate as a garnish, and yet it is fairly tasty in salads, smoothies, and as an ingredient in many main dishes. In my household, we often cut the stems with leaves and put them on the table in a glass of water, like a bouquet, to be eaten with almost any meal.

Both kale and parsley are well suited to growing in our cooler climate. Seeds of both can be planted outdoors early, almost as soon as the ground thaws, and will last long into the fall, providing nutrients and flavor well into November and December. As I write this article in mid-January I know there are live kale and parsley plants under the snow, which will send up green shoots early next spring. Both are biennial here, meaning they send up flower and seed stalks their second year. These flower stalks and their leaves can provide early spring greens while we wait for the new crop to sprout and grow to a reasonable size to pick. What I often do is wait until mid-summer when the seed stalks appear on the parsley, then pick the remaining leaves and stems and dry them for seasoning soups and other dishes in the winter. By that time, the new crop has attained enough size to begin harvesting the outer leaves for fresh use.

Both parsley and kale are also ornamental. I like to use parsley, the curly leaf varieties, as edgings along the borders of my beds. Kale now comes in so many varieties that they can be interspersed with flowers to liven up the colors and textures of ornamental beds. They follow tulips and daffodils especially well. While there are a few insects that will bother them, they are quite easy to grow.

Like other members of the brassica family, kale can be attacked by aphids, both in the garden and the greenhouse. My favorite remedy for aphids is a soap solution with garlic. A diluted spray will deter the little sap-suckers, and can be easily washed off with water when you are ready to eat the leaves.

Parsley, like other members of the Umbelliferae family, may attract small green caterpillars that eventually turn into beautiful Black Swallowtail butterflies. For that reason, I try not to spray them and just plant extra for the caterpillars, who rarely do much damage.