Rhubarb, Rheum rhabarbarum: A Tart Treasure in the Garden

Introduction:
Rhubarb, scientifically known as Rheum rhabarbarum, was a highlight at the Colorado Master Gardener Seed Social, attracting attention for both its culinary uses and distinctive appearance. This perennial vegetable is cherished for its tart, flavorful stalks, which are a staple in pies and desserts. Beyond its culinary appeal, rhubarb offers interesting features for any garden.

Exploring Rhubarb
Rhubarb is a hardy perennial known for its large, broad leaves and thick, red or green stalks. The plant can grow up to several feet in height, and while the stalks are edible, the leaves are toxic and should not be consumed. Rhubarb is typically harvested in spring and early summer.

Growing Rhubarb in Colorado
Rhubarb is well-suited to the Colorado climate. It prefers cooler weather and can be planted in areas with full sun to partial shade. Rhubarb thrives in well-drained, fertile soil and requires consistent moisture for optimal growth.

Planting and Maintenance

• Soil Requirements: Rhubarb grows best in a rich, well-drained soil. Adding organic matter will help to ensure healthy growth.
• Sunlight and Watering: The plant prefers full sun but can tolerate partial shade. Regular watering is important, especially during dry periods.
• Fertilization: A balanced fertilizer can be applied in early spring to promote healthy stalks.

Rhubarb (Rheum rhabarbarum) is a perennial vegetable that grows best in cooler climates and is typically well-suited to USDA Hardiness Zones 3 to 8. Here’s a breakdown of its suitability across these zones:

1. Zones 3–4: These are ideal zones for rhubarb, as the plant thrives in cooler temperatures. The cold winters in these zones help induce a period of dormancy, which is beneficial for the plant’s growth cycle.
2. Zone 5: Rhubarb also does well in Zone 5, experiencing a balance of cold winters and warm summers that are conducive to robust growth.
3. Zone 6: In Zone 6, rhubarb can be successfully grown, but it may start to struggle with the warmer temperatures, especially during the peak of summer. Providing some afternoon shade and ensuring adequate water can help mitigate heat stress.
4. Zone 7: Rhubarb’s performance in Zone 7 can be more challenging due to the warmer conditions. It’s important to choose a location that offers some relief from intense heat, such as partial shade, and to maintain consistent soil moisture.
5. Zone 8: Growing rhubarb in Zone 8 is possible, but it can be tricky due to the heat. It’s crucial to provide a cool, shaded environment, and the plant may require more frequent watering. In these warmer zones, rhubarb often behaves more as an annual rather than a perennial.

In zones warmer than 8, rhubarb’s growth becomes increasingly difficult due to the lack of a cold, dormant period and higher temperatures. Gardeners in these areas might have better success treating rhubarb as a cool-season annual, planting in the fall and harvesting in late winter or early spring before the heat sets in.

For optimal growth, rhubarb requires a period of winter chill, making it less suited for hot, tropical climates. It’s also worth noting that while rhubarb can survive in a range of zones, its productivity and lifespan might vary depending on the specific climate conditions of the area.

Medicinal Properties

• Historically, rhubarb has been used in traditional medicine for its laxative properties. Its roots contain compounds that can aid in digestion.
• It’s important to note that only the stalks should be used for culinary and medicinal purposes, as the leaves contain oxalic acid, which is toxic.

Culinary Uses

• Rhubarb is widely celebrated for its tart flavor, making it a popular ingredient in pies, tarts, and jams. It is often combined with strawberries or other sweet fruits to balance its tartness.
• Rhubarb can also be used in savory dishes, adding a unique flavor to sauces and stews.

Fresh Rhubarb Pie Recipe
Ingredients:

• 4 cups chopped rhubarb
• 1 1/3 cups white sugar
• 6 tablespoons all-purpose flour
• 1 tablespoon butter
• 1 recipe pastry for a 9-inch double crust pie

Instructions:

1. Prepare the Oven and Pie Crust:

• Begin by heating your oven to 450 degrees Fahrenheit (230 degrees Celsius).
• Place one piece of the pastry into a nine-inch pie pan.

2. Combine Rhubarb Filling:

• In a large mixing bowl, blend the chopped rhubarb with sugar and flour until thoroughly combined.

3. Assemble the Pie:

• Transfer the rhubarb mixture into the pastry-lined pie pan. Dot the top with small pieces of butter.
• Cover the filling with the second pastry piece. Seal the edges of the crust together, and make a few small slits in the top crust to allow steam to escape during baking.

4. Baking the Pie:

• Bake the pie in your preheated oven for 15 minutes.
• After the initial baking, reduce the oven temperature to 350 degrees Fahrenheit (175 degrees Celsius) and continue baking for 40 to 45 minutes more. The pie is done when the crust is golden brown and the filling is bubbling.

5. Cool Before Serving:

• Remove the pie from the oven and allow it to cool on a rack. Waiting for the pie to cool will help the filling set properly.

6. Serving:

• Serve the rhubarb pie either warm or at room temperature. It pairs beautifully with a scoop of vanilla ice cream or a dollop of whipped cream for added indulgence.

Enjoy your delightful and tangy Fresh Rhubarb Pie, a classic treat that brings the unique flavor of rhubarb to your dessert table!
Garden Aesthetics and Companion Planting

• Rhubarb’s large leaves and red stalks add an ornamental element to the garden. It can be used as a border plant or in a designated vegetable garden.
• Good companion plants for rhubarb include onions and garlic, as they can help deter pests.

Harvesting and Regrowth

• Harvest rhubarb by twisting and pulling the stalks from the base of the plant. It’s important to leave enough stalks on the plant to ensure continued growth.
• Rhubarb is a perennial and, if well cared for, can produce for many years.

Conclusion:
Rhubarb, Rheum rhabarbarum, offers a delightful combination of culinary value and visual appeal. Its tart, flavorful stalks are a springtime favorite in many kitchens, while the plant itself adds a unique and robust feature to the garden. Planting rhubarb not only promises delicious harvests but also contributes to the biodiversity and beauty of your garden.