Planting by the Numbers

Not all blueberries are created equal

Mmm-mmm, blueberries. Who doesn’t love them? When we can keep the birds from eating the fruit, this is surely one of the most rewarding edibles in the garden. They don’t take up a huge amount of space, and they are easy to grow in our area, given sun, acid soil and plenty of water. And the plants are beautiful, more or less year-round. To top it off, raw blueberries are among the most nutrient-rich plant foods available — low in calories and loaded with plant nutrients such as soluble fiber, minerals, vitamins and antioxidants. Antioxidants keep us healthy by scavenging free radicals, thereby preventing damage to DNA and other cell components and warding off cancers, aging, degenerative diseases and infections.

All blueberries are not created equal, however. According to a recent article in The New York Times (“Breeding the Nutrition Out of Our Food,” May 26) there is wide variation in the antioxidant content of blueberry varieties. Bluecrop, one of the most widely grown varieties in the U.S., contains only about one third the antioxidants of Elliott, for example. This variability is not unique to blueberries. Jo Robinson, the article’s author, reveals that virtually all our most important plant foods show similar variation and, moreover, that the most frequently eaten varieties of fruits and vegetables are far lower in plant nutrients than the wild food and heirloom varieties our ancestors ate.

A long-time champion of pasture-raised meat, eggs and dairy, Robinson turns her attention to plant foods in Eating on the Wild Side: The Missing Link to Optimum Health, a book recently published by Little, Brown and Co. Through 10,000 years of farming, Robinson argues, we’ve made our food less good for us, partly because humans have constantly selected against the bitter and astringent qualities inherent in nutrients such as antioxidants, while favoring mild flavor along with higher sugar, starch and fat content. We have also selected for other characteristics, such as disease resistance, appealing colors and lower fiber, without regard for nutritional value.

“The key to eating on the wild side,” Robinson says, “is to select those varieties that taste the best and come closest to the health properties of wild plants.” Mining 6,000 previously published articles, Robinson compared data for several modern day varieties of blueberry (Vaccinium corymbosum) with wild chokeberry (aronia), one of the berries most commonly eaten by North American hunter-gatherers. The blueberries ranged (in antioxidant units per gram of fresh weight) from 4.6 to 30.5, against 160 for wild chokeberries. An heirloom potato, purple Peruvian, has nearly 170 times the phytonutrients of a modern white potato. Other foods detailed in her Times article were corn, carrots, greens and apples. A liter of juice from a certain wild crab apple contains 100 times the nutrients of Golden Delicious and 35 times that of Granny Smith juice.

We may wonder about the practical meaning of these numbers. You might drink a liter of Granny Smith juice in the course of a day but would you drink a liter of aronia berry or crab apple juice? Probably not, even assuming you could find it. Dandelions have nearly eight times the antioxidants in spinach and 40 times as much as in iceberg lettuce (per hundred grams, fresh weight). But how many of us are likely to sit down to a large dandelion salad? How many antioxidant units do we need to stay healthy, anyway? Does anyone really know? What we do know is that we currently suffer from all manner of ills that are linked to poor diet, low in healthy plant foods. But as Robinson points out, urging people to eat more fruit and veg is not enough. We also need a palatable fruit and vegetable supply that provides the nutrients we need for optimum health.

Well, we do have blueberries. If you are going to plant some, why not plant those richest in antioxidants? Robinson lists 21 recommended varieties of blueberries in her book, she told me in an email. “The Rubel blueberry is one of the most nutritious. Small, dark and delicious. Most recently, I got four-year-old Rubel plants from Burnt Ridge Orchard, which is east of Centralia. Bladen and Bluegold are also unusually high in antioxidants.”

If you’d like to consider other criteria as well, such as time of ripening, size of fruit, bush size and fall color, a local blueberry grower, Fall Creek Nursery, has a very informative chart on their website.

Rachel Foster of Eugene is a writer and garden consultant. She can be reached at rfoster@efn.org.