Raising Veggies Part 1: Beautiful Brassica

The Roman Empire was in a fifty-year state of chaos before Diocletian came to the throne in 284 CE. Previous to his ascension, power rested in one emperor, but no one could agree on who that emperor should be, resulting in one political assassination after another. Diocletian thought he could end the madness by inventing a new political system with multiple emperors, and for a while it worked. Satisfied with the peace he brought Rome and now eager for such peace in his personal life, Diocletian abdicated and retired to his estate in Salona (modern-day Croatia).

His political solution was temporary, though, and in 308 the empire was on the verge of another civil war. Two of Rome’s leading politicians pleaded with him to return to power and do what he did before: pacify the realm. Diocletian was not interested, responding, “If you could see at Salona the cabbages raised by our hands, you surely would never judge that a temptation.” (The original Latin uses the word olera, which refers to vegetables and herbs in general, not the Latin word for cabbage which would be brassica. However, this imperfect translation tends to be the norm in English translation.)

He could have offered a multitude of alternative explanations, so we have to think Diocletian really did adore his cabbages. But what specifically about the cabbages did he love? Was it the act of gardening cabbages? The food made from cabbage? The use of cabbage as medicine? Or simply the relief of only having to garden and not run an empire?

Before addressing that question we need to admit that in the original Latin he didn’t refer to cabbages specifically; he used the Latin word olera, which refers to vegetables and herbs in general. It was Edward Gibbon in his masterpiece The History of the Decline and Fall of the Roman Empire who chose to translate the word as “cabbage”, with other translators following.

If Diocletian wanted to single out cabbage specifically he would have used the Latin word brassica, but even if he did, there would still be some ambiguity. Today we think of cabbage as the plant that produces a large and tight ball of crunchy leaves. A plant that, when harvested, most resembles a soccer ball. For a Roman foodie, though, brassica referred to the “cole” plants in general, which include broccoli, kale, cauliflower, kohlrabi, and brussel sprouts, in addition to what we today call cabbage. There is even variety called Walking Kale or Jersey Cabbage which grows stalks large enough to be used as walking sticks. Later, when Linnaeus created the scientific taxonomy for living organisms in the 18th century, all of the cole plants would be placed under the species Brassica oleracea. Cabbage and broccoli are the same species, just different varieties.

Varieties of the Brassica oleracea species

Broccoli was bred to produce a large number of flower buds that are tasty when immature. Cabbage was bred to avoid producing a big stem in youth, hence the tight spherical collection of leaves. Both are valued for their youthful behaviors and that value is lost if they are allowed to mature. The broccoli heads you eat, if left on the plant, will bolt, spread out, and turn into pretty yellow but not so tasty flowers. The cabbage plant, if not harvested early, will eventually produce a tall and thick stem, growing up to three feet tall with few of the leaves we like to eat. Dr. Norwood once let a head of cabbage keep growing well beyond its proper harvesting stage, and it turned into the monstrosity you see below!

When you let cabbage just keep growing!

The brassica grown by Diocletian would have looked more like kale than broccoli or cabbage. While it didn’t take on the wide variety of forms the Brassica oleracea species does today, there were distinct varieties. We know this from the writings of Cato the Elder in 160 BCE, who describes one variety as having smooth, large leaves with a large stalk, another as having crumpled leaves, and a wild variety which was said to possess greater “strength”.

What did he mean by “strength”? In the modern world we tend to separate “food” from “medicine”, but for Cato the Elder and Diocletian they were one in the same, and when Cato said the wild cabbage had “strength” he meant that it was a particularly potent medicine.

Medicine for what, you may ask? All kinds of things, from digestive problems to vision—even hair loss—could be remedied by the brassica. Being medicine, our ancient ancestors would sometimes consume it not as a vegetable but as a roborant, meaning they would sometimes boil the cabbage, skim off the water containing the cabbage juices, and drink that. It was even thought that children who bathed in the urine of people who ate brassica would grow larger and stronger.

The major health benefit of brassica was its protection against drunkenness and cure for hangovers. Pliny the Elder (24 – 79) wrote that eating brassica before drinking keeps you from getting too drunk, and if you have a hangover brassica can get rid of it. Cato the Elder once remarked, “After dinner, eat some half a dozen [brassica] leaves; it will make you feel as if you had not dined, and you can drink as much as you please.”

The brassica plant was likely domesticated in the Mediterranean, where its wild ancestor, commonly known as wild cabbage, still thrives on cliffs overhanging the sea. The wild cabbage is tough, but its domesticated version was selected for taste, and so is somewhat wimpy, which means it must be given considerable care when growing. You don’t just bury the seed in the field where you want the plant to grow. Even in ancient times they were first grown in a “nursery”, meaning a plot with an ideal soil replete with plant nutrients, in an area that was generally kept warm, and in an area that would be watered and weeded continually. Then, once the plant is bigger, you move it out to the field.

The writer Columella (4 – 70 AD) described raising brassica plants like this. You germinate the seed in a nursery. When the seed has germinated and the plant has six leaves it is ready to transplant. For transplanting, you dip the roots in a liquid manure, and plant it in the ground with algae. The idea is that the young brassica plant needs to be coddled before taken the field, and when in the field it needs to have an adequate amount of nutrients.

Around the time Columella was writing about this, the first “greenhouse” as built. Emperor Tiberius (14 BC to 37 AD) had an intense love for cucumbers and never wanted to be without them. So his people made raised beds on carts on which they grew cucumbers. When it was warm they would roll the cucumber beds outside, but when it was cold they would roll the beds inside a building built with thin sheets of mica, a silicate mineral, which, if thin enough, is semi-transparent, meaning it lets light in and you can see through it (but not as transparent as modern glass). The building wasn’t called a greenhouse but a specularia. I’m sure some Roman gardeners and farmers used the specularia to start brassica plants for later transplanting into a field.

We too love the brassica, and appreciate the many shapes and forms it can take, both due to their beauty and the variety of flavors they provide. In the South it is a sin to eat barbeque without coleslaw, which of course is made with cabbage. Broccoli and cauliflower are common in Asian stir fries, Brussell sprouts are an ideal roasting vegetable, and kale can really spruce up an otherwise bland salad. While we no longer consider them “medicine” in the same way we do antibiotics, the brassica are one of many vegetables considered part of a healthy diet. (Of course, no one takes them as a hangover cure anymore!) Moreover, we raise them in much the same way, starting them by seed in a greenhouse and later transplanting them into a field, and like Diocletian, a gardener can obtain considerable joy from watching the brassica plants begin looking all alike as seedlings and then taking their unique and varied shapes and flavors.

References

Janick, J., & Paris, H. (2022). History of controlled environment horticulture: ancient origins. HortScience, 57(2), 236–238. https://doi.org/10.21273/HORTSCI16169-21

Maggioni, L., von Bothmer, R., Poulsen, G., & Lipman, E. (2018). Domestication, diversity and use of Brassica oleracea L., based on ancient Greek and Latin texts. Genetic Resources and Crop Evolution, 65(1), 137–159. https://doi.org/10.1007/s10722-017-0517-7

Pseudo-Aurelius Victor. (1911). Epitome de Caesaribus (F. Pichlmayr, Ed.). Teubner.

Muckenhoupt, M. (2018). Cabbage: A global history. Reaktion Books.