Rhubarb is a hardy perennial that thrives in various soil types and conditions. This low-maintenance crop produces abundant stalks for years, making it a favourite among Britons who can grow it easily in the ground or in pots.
It’s easy to spot with its ruby red, pink, and green hues, which give it a unique appeal as the stems grow taller. But if gardeners pluck the fruit from the ground too eagerly, they may struggle to secure an abundant future harvest. Gardening experts at Thomson & Morgan warned: “Rhubarb plants are very low maintenance, but they will produce better crops if given a little extra care and attention according to the season.” Spring and summer are crucial for anyone with rhubarb in their garden.
Rhubarb is typically ready to harvest from spring, starting around late April or May for established plants.
Before picking the ripe stems, check your plant for flowers. Once the plant reaches maturity, these often appear in spring.
The quirky-looking blooms grow at the top of long stalks that are longer than the edible stalks. They resemble malformed cauliflowers with a pinkish tone.
Developed clusters look like cream-colored panicles that resemble oversized astilbe flowers. Though intriguing, the flowers are useless to your crop: “Remove rhubarb flowers as they appear in order to direct the plants’ energy into growing tasty stems”, says the Thomson & Morgan team.
Rhubarb ready for harvesting should have six to 10 leaves, and the stalks will show clear signs. Stems from 18cm to 40cm long that feel thick and firm are ready to be pulled and enjoyed.
But there’s more to it, according to Dene Wood, head gardener at the National Trust’s Clumber Park in Nottinghamshire.
They told Saga Magazine that gardeners should pick leaves from the outside first: “This is a bit of a skill – grasp the stem near the base, then pull and twist at the same time.”
While some people cut their rhubarb, this should be avoided. It often leaves material behind in the crown, which can rot and become mouldy.
The method is simple: grab the stalk low to the ground, push it gently downward, then pull up with a slight twist.
Harvesting rhubarb before it has six to 10 leaves can be as damaging as over-picking.
Gardeners can continue to pluck the sour stems until early summer, but it’s best to stop by June or July to allow the plant to recharge for the next season.
It’s also worth monitoring rhubarb as summer approaches – you may need to water plants during dry periods.
The Thomson & Morgan team recommends ensuring the soil doesn’t dry out. They noted that rhubarb grown in containers will need to be watered much more often to keep the compost moist.