A month or so back I wrote about lilacs, and the uncanny ability their scent possesses of being able to transport you out of time and place to sunny moments of your past. But for me, there’s another plant with similar abilities – though through a very different manner of delivery – that’s just now at its height: rhubarb. I can’t look at a clump without thinking of my mother, and how each June she transformed the sour stalks into a wonderfully piquant compote—a special treat to be poured over fruit in the morning before school. Whenever that delicious crimson-colored sauce appeared on the table, I knew the end of classes couldn’t be far behind.
Looking back, I realize that our family was never without rhubarb. Its bright crimson stalks and huge green leaves appeared each spring in every one of the gardens I knew as a boy, heralding the warm weather to come. And each of the three times we moved, a portion of the original plant would accompany us into our next garden. Once, having forgotten to take the rhubarb with us, we even made a special trip to our former house to beg a division from the new owners— such was the displacement each of us felt without its familiar presence.
Commonly mistaken for a fruit, rhubarb is actually a vegetable – a member of the buckwheat family of all things – and closely related to garden sorrel (another favorite of mine). Though many species are grown throughout the world, it is the common garden-variety rhubarb, Rheum rhabarbarum, also known as Rheum rhaponticum with which we are most familiar here in the US.
Like many plants, rhubarb’s origins date back to ancient China, where its roots (rhizomes) and stalks (petioles) were prized for their purgative and other medicinal qualities. While several species are native to parts of Siberia, northern India and Nepal (some found as high as 14,000 feet!), it is the Chinese variety —Rheum palmatum—that first made it to Europe. One of rhubarb’s earliest proponents was Marco Polo, who traveled throughout China in the 15th century wrote extensively about it in his journals. By the mid 1500s, rhubarb’s use as an intestinal cleaner was already widely known throughout Europe. And it to these laxative properties that Shakespeare’s Macbeth clearly refers when he cries out “What rhubarb, senna, or what purgative drug would scour these English hence?”
In fact, the plant’s history is so long that even its etymology is somewhat obscured. In the English language, the word ‘rhubarb’ made its first appearance around the mid 1400s. According to Lindley’s Treasury of Botany, the genus Rheum derives from Rha— the ancient name for the Volga river in Russia, on whose banks the plant was said to grow. Others called it rha barbarum, or “of the bearded peoples”, referring to all those rhubarb-eating, “bearded” (Lat:barbarus) tribes in northern Europe.
For all its medicinal and ornamental attributes, in America rhubarb has been grown primarily for its taste. Introduced into the New England colonies between 1790-1800, the hardy plant endeared itself to the early colonists and by 1822 was widely available in Massachusetts produce markets. Its thick, fibrous stalks were stewed and sweetened to make everything from preserves and compotes to wine to that great American culinary icon: the rhubarb pie.
With its large, attractive leaves, bright red or crimson-colored stalks, and the tall, spiky flowers of ornamental varieties such as Rheum officinale and Rheum emodi, it is no wonder that in England rhubarb has long been a favorite of the perennial border. And though still somewhat hard to find, ornamental varieties have been cropping up in American gardens as well in recent years. (The only source I know of in the US is Heronswood Nursery based in Washington State. One of the founders, Dan Hinkley, is positively mad about rhubarb, having traveled as far as Tibet, weathering high altitude, monsoon rains, and even hungry yaks, to seek out ever new varieties. The descriptions themselves are worth the read. Describing Rheum alexandrae, for example: “…[a] resplendent species with spikes of flowers rising to 3′ completely shielded by large, translucent white bracts, and I scanned the entire shore of Tianchi Lake in Yunnan for remaining seed of this common species at 12,000 ft., and finally found a few remaining from the ravages of summer-grazing yaks, though totally soaked my shoes in the process of retrieval.”) For you heirloom fans, one of the most common varieties found in nurseries today is ‘Victoria’, dating back to 1863.
In terms of culture, very few plants could be easier to grow, or give so much for so little effort, than the rhubarb. A cool season perennial crop, rhubarbs send out stalks from April through September and require temperatures below 40 F in the winter to stimulate bud break and below 90 F in the summer to sustain active growth. Once established, rhubarb is generally untroubled by pests, and extremely long- lived (plants are productive indefinitely if given a heavy top dressing of manure or compost each fall.)
Rhubarb is produced from crowns consisting of rhizomes and buds. It can also be grown from seed, though this method is not recommended as the seedlings don’t retain the characteristics of the parent plant. For maximum crop production, set root divisions about three feet apart in well-drained soil that is heavily composted with manure or peat. The crown bud should be set about two inches below the surface. Good drainage is essential to help ensure against rotting, and planting in raised beds is ideal. Harvesting occurs throughout the spring into early summer, though you should cease by mid July to let the plant regenerate for the next year. Ideally, You should forgo harvesting the plant until the second year to allow it to establish itself. Just be sure to trim the leaves off before cooking – unlike the stalks, the foliage contains highly poisonous oxalic acid, and can even kill if consumed in large quantities.
Recipe: Rhubarb Crumble
This is one of my favorite recipes from my Cultivated Gardener radio days. The sourness of the rhubarb is perfectly paired with the sweetness of the crumble, creating a delicious balance. The whole thing can be made in very little time, although try to leave at least half an hour to “marinate” the rhubarb slices in sugar to soften. Mix in a few sliced spring strawberries for a real treat and serve topped with vanilla ice cream, whipped cream, a drizzle of heavy cream or a dollop of creme fraiche.
4 cups fresh rhubarb, cut into 1-inch pieces
1/2 cup sugar
1 teaspoon ground ginger
1/2 teaspoon ground cinnamon
1/2 cup flour
1/3 cup brown sugar
1 cup granola, preferably with nuts
1 stick unsalted butter, cut into cubes
Toppings: vanilla ice cream, whipped cream, heavy cream or a dollop of creme fraiche
Place the rhubarb in a bowl and sprinkle with the half cup sugar. Add half teaspoon of the ginger and a quarter teaspoon cinnamon. Let “marinate” for at least thirty minutes, and up to two hours.
Meanwhile, mix the flour and sugar in a bowl. Add the granola and the remaining ginger and cinnamon. Add the butter and, using your hands or a pastry knife, break the butter into the mixture until it is the size of peas.
Preheat the oven to 350 degrees. Lightly butter the bottom of a pie plate or medium-size gratin dish. Add the rhubarb chunks. Spoon the crumble topping on it and press down to form a crust. Make sure the butter isn’t all in one clump, but distributed through the crust. Bake on the middle shelf for about 20 to 35 minutes, or until the rhubarb is soft and the fruit is beginning to bubble under the crust; the crust should be golden brown. Remove from the oven and serve hot or at room temperature with any of the toppings. Serves 4.