Rhubarb, with its vibrant pink and green stalks, is a springtime delight that adds a tangy twist to pies, crumbles, and jams. But many gardeners and cooks wonder: does rhubarb go out of season? The answer is a bit more nuanced than a simple yes or no. Let’s delve into the seasonal life cycle of rhubarb, exploring when it’s at its peak, how to extend its availability, and what factors influence its growth.
Understanding Rhubarb’s Natural Growing Season
Rhubarb is a perennial plant, meaning it lives for more than two years. In fact, with proper care, a rhubarb plant can thrive for decades. Its growth cycle is closely tied to temperature. Rhubarb needs a period of cold dormancy, typically below 40°F (4°C), to trigger growth in the spring. This chilling period is crucial for the plant to produce abundant, flavorful stalks.
The traditional rhubarb season is spring, typically from April to June. During this time, the stalks are tender, juicy, and have the best flavor. As the weather warms up in late spring and early summer, the plant begins to focus on producing leaves rather than stalks. The leaves, it’s important to note, are poisonous and should never be consumed.
The Peak Season for Rhubarb: A Time of Abundance
The peak rhubarb season usually occurs in May. During this month, rhubarb plants are at their most productive, yielding thick, colorful stalks perfect for cooking and baking. Gardeners often harvest rhubarb multiple times during May, enjoying the bounty of this early-season vegetable (yes, botanically, it’s a vegetable, though often treated as a fruit in culinary applications).
However, as summer progresses, the quality of rhubarb stalks declines. They can become tougher, more stringy, and the flavor can become less intense. This is why many gardeners stop harvesting rhubarb by the end of June or early July.
Extending the Rhubarb Season: Techniques and Considerations
While the natural rhubarb season is relatively short, there are ways to extend its availability. Understanding these techniques can help you enjoy rhubarb for a longer period.
Forcing Rhubarb: An Early Start
Forcing rhubarb is a technique that allows you to harvest rhubarb earlier in the season, sometimes as early as February or March. This involves covering the rhubarb plant with a large container, such as a terracotta forcing jar or a large bucket, to exclude light. The lack of light encourages the plant to produce tender, pale pink stalks.
Forcing rhubarb weakens the plant, so it’s essential to only force established plants that are at least three years old. Also, you should not force the same plant two years in a row, as this can deplete its energy reserves.
Succession Planting: A Continuous Harvest
Another way to extend the rhubarb season is through succession planting. This involves planting different varieties of rhubarb that mature at different times. Some varieties, like ‘Victoria,’ are early producers, while others, like ‘Canada Red,’ mature later in the season. By planting a mix of varieties, you can enjoy a longer harvest period.
Freezing Rhubarb: Preserving the Taste of Spring
One of the best ways to enjoy rhubarb year-round is to freeze it. Rhubarb freezes exceptionally well, retaining its flavor and texture. To freeze rhubarb, simply wash and chop the stalks into 1-inch pieces. Blanching the rhubarb for a minute or two can help preserve its color and texture, but it’s not essential. Spread the chopped rhubarb on a baking sheet and freeze until solid, then transfer it to a freezer bag or container. Frozen rhubarb can be stored for up to a year.
Factors Affecting Rhubarb’s Seasonality and Growth
Several factors influence rhubarb’s seasonality and overall growth. Understanding these factors can help you grow healthier, more productive rhubarb plants.
Climate and Temperature: The Key Drivers
As mentioned earlier, rhubarb requires a period of cold dormancy to thrive. In regions with mild winters, rhubarb may not grow as well, or it may produce smaller, less flavorful stalks. Similarly, in regions with very hot summers, rhubarb growth can be stunted. Rhubarb prefers cool, moist conditions.
Soil Conditions: The Foundation for Growth
Rhubarb thrives in rich, well-drained soil. It prefers a slightly acidic soil pH, around 6.0 to 6.8. Amending the soil with compost or well-rotted manure can improve its fertility and drainage.
Watering and Sunlight: Essential Elements
Rhubarb needs consistent moisture, especially during the growing season. Water deeply and regularly, especially during dry spells. Rhubarb also needs at least six hours of sunlight per day. However, in hotter climates, some afternoon shade can be beneficial.
Pest and Disease Management: Protecting Your Crop
Rhubarb is generally a hardy plant, but it can be susceptible to certain pests and diseases. Common pests include rhubarb curculio, a type of weevil that can damage the stalks. Diseases include crown rot, which can be caused by poor drainage. Implementing good garden hygiene practices, such as removing dead leaves and ensuring good drainage, can help prevent these problems.
Rhubarb Beyond the Traditional Season: Finding Rhubarb Out of Season
While the peak rhubarb season is in spring, it’s sometimes possible to find rhubarb out of season, though it may be less common and potentially more expensive.
Greenhouses and Indoor Growing: A Controlled Environment
Some growers use greenhouses or indoor growing techniques to produce rhubarb out of season. This allows them to control the temperature and growing conditions, extending the harvest period. Greenhouse-grown rhubarb is often available in the fall or winter, although it may not be as flavorful as spring-grown rhubarb.
Frozen Rhubarb: A Convenient Option
As mentioned earlier, frozen rhubarb is a great way to enjoy this tart treat year-round. Most grocery stores carry frozen rhubarb, making it a convenient option for those who don’t have access to fresh rhubarb.
Specialty Markets and Farm Stands: A Seasonal Treat
Depending on your location, you may be able to find fresh rhubarb at specialty markets or farm stands outside of the traditional spring season. These sources may offer locally grown rhubarb that has been forced or grown in a greenhouse.
In conclusion: The Seasonal Nature of Rhubarb
So, does rhubarb go out of season? The answer is generally yes, but with some caveats. The natural rhubarb season is primarily in the spring, from April to June, with May being the peak month. However, with techniques like forcing, succession planting, and proper preservation methods like freezing, you can extend the availability of rhubarb. Additionally, greenhouse-grown rhubarb and specialty markets may offer rhubarb outside of its traditional season. Understanding rhubarb’s seasonal life cycle and the factors that influence its growth can help you enjoy this delicious and versatile vegetable for a longer period. Remember, always discard the leaves and only consume the stalks! The vibrant color and tangy flavor of rhubarb are well worth the effort to grow and enjoy this seasonal treasure.
Does rhubarb truly have a defined season?
While often considered a spring vegetable, rhubarb’s season is more nuanced than a simple on/off switch. The main harvest period for commercially grown rhubarb generally runs from April to June, with the stalks being most tender and flavorful during this time. This is due to the plant’s optimal growing conditions during cooler temperatures and increased moisture, leading to vigorous growth and less stringy stalks.
However, it’s possible to harvest rhubarb later in the season, even into early summer. The stalks may become tougher and more acidic, requiring extra preparation to make them palatable. Gardeners can also “force” rhubarb in late winter/early spring by covering the plant to block sunlight, resulting in an earlier and more tender harvest. Ultimately, while peak season is spring, rhubarb’s availability extends somewhat beyond that, making it a relatively long-season crop.
Why does rhubarb taste better in the spring?
Spring rhubarb possesses a desirable balance of sweetness and tartness, along with a tender texture that makes it ideal for pies, jams, and other desserts. This is because cooler temperatures during the spring months encourage sugar production within the stalks while simultaneously slowing down the development of the tougher fibers that can make older rhubarb stringy. The young stalks also tend to have a higher water content.
As the weather warms up in the summer, rhubarb stalks become more fibrous and the concentration of oxalic acid increases, contributing to a more intensely tart and sometimes slightly bitter flavor. While still usable, later-season rhubarb may require more sugar and longer cooking times to achieve the desired taste and texture, highlighting why spring rhubarb is generally preferred.
Can you still eat rhubarb after the peak season?
Yes, you can still eat rhubarb after its peak season, but with a few considerations. While the stalks might be tougher and more tart, they are perfectly safe to consume as long as the leaves are removed and discarded (as they are always poisonous). Adjusting your recipes to compensate for the altered flavor and texture is key.
To make the most of late-season rhubarb, peel the stalks to remove the tougher outer layers. This helps reduce the stringiness. You may also need to add more sugar to balance the increased acidity and cook it for a longer time to soften the fibers. Alternatively, consider using it in chutneys or sauces, where the intense flavor is an advantage and the texture is less noticeable.
How does forcing rhubarb affect its season?
Forcing rhubarb is a technique that allows gardeners to harvest rhubarb earlier than its typical season. By covering the plant with a dark container, such as a rhubarb forcer or even an overturned bucket, sunlight is blocked. This lack of light encourages the plant to put all its energy into stalk production, resulting in long, tender, and often sweeter stalks.
The process effectively tricks the plant into thinking it’s spring, leading to a harvest several weeks or even months earlier than unforced rhubarb. Forced rhubarb is prized for its delicate flavor and pale pink color. It’s important to note that a plant should not be forced every year, as it can weaken it over time.
How do you store rhubarb to extend its usability beyond the season?
Freezing is the most effective way to store rhubarb and preserve its flavor and texture for use beyond its natural season. To prepare rhubarb for freezing, wash the stalks thoroughly and trim off the leaves and the ends. Cut the stalks into 1-inch pieces.
Next, blanch the rhubarb pieces in boiling water for one minute, then immediately plunge them into ice water to stop the cooking process. This helps to preserve the color and texture of the rhubarb. Drain the rhubarb well and then spread it out in a single layer on a baking sheet. Freeze until solid, then transfer the frozen pieces to freezer bags or containers. Properly frozen rhubarb can last for up to a year.
What factors affect rhubarb’s season and growth?
Several factors influence rhubarb’s growth and season. Climate plays a crucial role, with cooler temperatures and ample moisture being ideal. Rhubarb thrives in regions with cold winters, as the dormancy period is necessary for vigorous growth in the spring. Soil type also matters, as rhubarb prefers well-drained, fertile soil rich in organic matter.
Beyond climate and soil, adequate sunlight is essential for rhubarb growth, although it can tolerate some shade. Proper watering is also critical, especially during dry periods. The age of the plant can also influence harvest time and quality, with established plants generally producing larger and more abundant harvests. Regular fertilization helps to maintain healthy growth and extend the plant’s productive lifespan.
Is there a difference between spring and summer rhubarb varieties?
While there aren’t distinct rhubarb “varieties” categorized solely as “spring” or “summer” types, different cultivars exhibit varying levels of tartness and fiber content that can influence their usability throughout the season. For example, some red-stalked varieties like ‘Victoria’ tend to be less tart than green-stalked varieties and may remain palatable for a longer period.
Generally, all rhubarb will become more fibrous and tart as the season progresses, regardless of the specific cultivar. However, some varieties naturally produce stalks with fewer strings and a milder flavor, making them more suitable for harvesting later in the season. Ultimately, the decision of when to harvest rhubarb should be based on the individual plant’s appearance, the desired flavor profile, and the intended use.