Rhubarb is botanically a perennial vegetable, though it is commonly treated as a fruit in culinary preparations. The plant is prized for its tart, edible stalks, which typically appear in gardens during the spring and summer months. The process known as “forcing” is a specialized agricultural technique used to manipulate the plant’s natural growth cycle. This method produces a tender, early-season crop, significantly extending the availability of fresh rhubarb into the colder months.
Defining Forced Rhubarb
Forced rhubarb is distinct from its field-grown counterpart, possessing different physical and flavor characteristics. The stalks are thinner, much more tender, and display a vibrant pink or crimson color with small, pale yellow leaves. This unique appearance results from the specific growing conditions, which prevent the development of chlorophyll. The resulting product has a significantly lower acidity and a milder, sweeter flavor profile because the plant uses stored carbohydrates in its root to fuel its rapid growth, converting starches into glucose.
The Specialized Growing Process
The forcing process begins with established rhubarb crowns, which are grown outdoors for at least two years to build substantial energy reserves in their roots. Before being moved indoors, the crowns must be exposed to cold temperatures, often including a hard frost, to break their natural winter dormancy. Once dormant, the crowns are carefully moved into specially constructed, long, low forcing sheds that are completely dark and heated.
The darkness is the central mechanism, triggering a growth response called etiolation, which causes the shoots to stretch rapidly upward. This rapid, light-deprived growth prevents the formation of tough fibers, yielding the characteristic tender texture. Growers maintain the pitch-black environment so rigorously that harvesting is traditionally done by candlelight to prevent light exposure, which would instantly initiate photosynthesis. A unique feature of these sheds is the low, creaking, and popping sounds that can be heard as the stalks grow quickly.
Geography and Timing of Production
The practice of forcing rhubarb is historically concentrated in a small area of West Yorkshire, England, known globally as the “Rhubarb Triangle.” This region, roughly delineated by Leeds, Wakefield, and Bradford, benefits from ideal soil and microclimatic conditions, including cold winters that ensure deep dormancy. In 2010, Yorkshire Forced Rhubarb was awarded Protected Designation of Origin (PDO) status, formally recognizing the unique nature of this product.
This specialized cultivation is primarily a winter commodity, with the harvesting season running from late December or January until the end of March. The process provides consumers with a fresh, high-quality crop during the seasonal gap when field-grown rhubarb is unavailable. Once a crown has been forced, its energy reserves are exhausted, and it must be discarded or allowed several years to recover fully before it can be forced again.
Using Forced Rhubarb in the Kitchen
The delicate texture and milder taste of forced rhubarb make it highly prized by chefs and home cooks. Its low acidity means significantly less added sugar is required to balance the flavor compared to summer-grown rhubarb. The tender stalks also cook much faster, making them ideal for poaching or creating light, delicate desserts. While field rhubarb is often better for heartier crumbles, the forced variety is increasingly used in savory dishes to provide a sharp, clean counterpoint to fatty meats or oily fish.