What is “glass rhubarb”?
“Glass rhubarb” is rhubarb that’s forced to grow early by being kept in darkness, usually under a bucket, large pot, or a traditional forcing jar. The goal is simple: block light and create a sheltered microclimate so the plant sends up stalks sooner. The result is pale, sometimes almost translucent stalks that are famously tender and often milder in flavor than rhubarb grown in full light.
Why does forced rhubarb become paler and more delicate?
When rhubarb grows with little or no light, photosynthesis is reduced. The plant stretches upward in search of light, producing longer, softer stalks with a lighter color. Many people describe the taste as cleaner and less aggressively sharp, which makes forced rhubarb ideal when you want a refined rhubarb flavor in both cooking and drinks.
When is forced rhubarb ready to harvest?
Forced rhubarb is an early spring treat. Timing depends on climate and where the plant sits, but the key is harvesting while the stalks are still tender. Once stalks get thicker and tougher, you lose the main benefit of forcing: that crisp, delicate bite.
How to force rhubarb at home: step by step
1) Start with an established plant
Use a rhubarb crown that’s at least 2–3 years old and growing strongly. Avoid forcing newly planted rhubarb.
2) Cover early, as buds appear
When you see buds pushing up in spring, place a large, opaque container over the crown: a black bucket, an upside-down pot, a storage tub, or a forcing jar. Darkness is the point.
3) Keep conditions steady
Make sure the cover sits securely and blocks light from the sides. Try not to lift it often—every peek lets light in and can reduce the “glass” effect.
4) Harvest the right way
Harvest stalks when they’re pale and still feel crisp and tender. Twist and pull gently from the base rather than cutting, which helps avoid leaving stubs that can rot.
5) Let the plant recover
Forcing draws energy from the crown. Think of it as a limited early harvest, not a full-season strategy. After you’ve taken a small harvest, remove the cover and let the plant grow normally for the rest of the season.
Common mistakes that reduce quality
Forcing weak or young plants
If the crown isn’t strong, forcing can set it back. Prioritize plant health first.
Waiting too long to harvest
Older forced stalks quickly lose their tender texture. Harvest sooner for the best result.
Using the leaves
Rhubarb leaves are not edible. Use only the stalks.
How to use forced rhubarb in food at home
1) Quick compote for breakfast or dessert
Slice forced rhubarb and simmer briefly with a little sugar and a splash of water until just softened. Flavor with vanilla, cardamom, or fresh ginger. Serve with yogurt, pancakes, or vanilla ice cream.
2) Slow-roasted rhubarb for clean flavor
Lay stalks in a dish, sprinkle with sugar, add lemon zest, and roast gently until tender but still holding shape. This method highlights the delicate character of forced rhubarb.
3) Rhubarb topping for cheese boards
Cook down forced rhubarb into a jammy topping with sugar and a little citrus. Spoon it next to aged cheeses, crackers, and charcuterie for a bright spring contrast.
How to use forced rhubarb in drinks at home
1) Rhubarb syrup for cocktails and zero-proof drinks
Simmer chopped forced rhubarb with sugar and a little water, then strain. Use the syrup in a spritz, a G&T twist, lemonade, or sparkling water with citrus.
2) Rhubarb lemonade with a sharper edge
Mix rhubarb syrup with fresh lemon juice and cold water. Serve over ice and finish with mint. For a more grown-up version, top with soda water.
3) Rhubarb shrub as a flavor base
A shrub is a sweet-tart vinegar syrup that works beautifully in both cocktails and alcohol-free drinks. Macerate rhubarb with sugar, then stir in apple cider vinegar and chill. Add a splash to sparkling water over ice.
Quick checklist for success
Use a mature, healthy rhubarb crown
Cover early and keep it dark
Harvest while stalks are pale and tender
Remove the cover and let the plant recover
