🌿 When to Plant Rhubarb

Rhubarb is one of the few true perennial vegetables, returning faithfully every spring for a decade or more from a single planting. Unlike most crops, patience is part of the deal: you skip the harvest in year one, go easy in year two, and by year three you are rewarded with a nearly self-sufficient plant that asks little in return. Cool winters are the price of admission, since rhubarb needs sustained cold to break dormancy and push out those thick, tart stalks each spring.

Variety Selection

Most nursery crowns arrive unlabeled and will grow just fine. If you are ordering from a specialty catalog, a few named varieties are worth knowing.

Victoria is the most widely available open-pollinated variety, producing long greenish-to-pink stalks with reliable yields. It is a solid baseline choice for zones 3-7 and is one of the easiest to find both as crowns and seed.

Canada Red and Crimson Red produce deeply colored red stalks and tend to be slightly sweeter than green types, making them popular for jams, pies, and any preparation where appearance matters.

Valentine, developed in Minnesota, has vivid red stalks and strong cold hardiness, a good pick for zones 3-4 where winters are severe and you want a variety that can take a hard freeze without complaint.

Glaskins Perpetual matures faster than most varieties and is often marketed as allowing a light harvest in year one. Even so, restraint in that first season pays off in years to come: let the plant establish fully before cutting more than a stalk or two.

Spacing, Sun, and Soil

Rhubarb plants grow large. Give each crown at least 3-4 feet of space in all directions, with 4-5 feet between rows if you are planting several. Cramped conditions lead to weak stalks and increase disease pressure.

Sun: Full sun (six or more hours daily) produces the thickest, most productive stalks. In zones 7-8, afternoon shade helps reduce heat stress and extends the harvest window into late spring.

Soil: Rich, deep, well-draining soil is essential. Work 2-3 inches of compost into the bed before planting. Rhubarb prefers a soil pH between 6.0 and 6.8. Avoid low spots where water pools; standing water around the crown is the leading cause of rot.

Planting depth: Set crowns 1-2 inches below the soil surface with the buds facing up. Deeper planting slows emergence; shallower planting risks frost damage to exposed buds in zones 2-4.

Top Growing Tips

• Never eat the leaves. They contain oxalic acid at levels that are toxic to people and pets. Discard them rather than adding them to the salad bowl.
• Skip the harvest in year one entirely. Every stalk left on the plant is energy going back into the root system that will pay dividends for years.
• Cut any flower stalks off at the base the moment they appear. Bolting redirects energy from stalk production and, left unchecked, makes remaining stalks thin and pithy.
• Red-stalked varieties tend to be sweeter than green types, though both cook down the same way once enough sugar is added.
• Divide crowns every 4-5 years in early spring, before growth begins. Each division should have at least one healthy bud and a good chunk of root.
• In zones 6 and colder, mulch over the crown in late fall with 3-4 inches of straw or shredded leaves to buffer against hard freeze-thaw cycles.

Watering

Rhubarb is fairly drought-tolerant once established, but consistent moisture through spring and early summer produces thicker, more succulent stalks. Aim for 1-2 inches per week from rain or supplemental irrigation during the active growing season.

Water at the base of the plant rather than overhead to keep the crown and foliage dry, which reduces the risk of fungal problems. Once you stop harvesting for the season and summer heat sets in, the plant can get by on less water as it rebuilds its carbohydrate reserves for next year.

Companion Planting

Good companions: Strawberries are the classic pairing, and the combination earns its reputation. They share similar moisture needs, ripen at overlapping times, and the broad rhubarb canopy provides some protection from late spring frosts. Garlic and onions planted nearby may help deter aphids. Asparagus is another compatible perennial neighbor that won’t aggressively compete with rhubarb’s deep root system.

Avoid planting near: Dock and knotweed belong to the same plant family (Polygonaceae) as rhubarb and can harbor shared pests and diseases. Keep them out of the garden entirely if possible, or at least well away from the rhubarb bed. Heavy feeders like squash planted in very close proximity can deplete soil nutrients and create real competition in a small bed.

Common Problems

Crown rot is the most serious rhubarb problem, caused by Phytophthora and related water molds. Plants in poorly draining soil develop soft, mushy crowns and collapse suddenly. Prevention is the only reliable fix: plant in well-drained soil, and never let water pool at the base.

Bolting is common in stressed or aging plants. Heat spikes, overcrowding, and drought all trigger it. Remove flower stalks promptly and consider dividing the crown if bolting becomes a recurring problem each season.

Rhubarb curculio is a rust-colored beetle that bores into stalks and crowns, leaving weeping sap and soft spots. Inspect plants in early summer and hand-pick adult beetles in the morning when they are slow. Remove and destroy any infested stalks before the damage spreads to the crown.

Powdery mildew appears as a white coating on leaves during humid stretches, but it rarely affects stalk quality. Keep spacing generous and remove any leaves that crowd the base to improve airflow.

Harvest Timeline

Year 1: Do not harvest. The crown is building the root mass that will sustain production for the next decade or more.

Year 2: Take one or two stalks per plant at most, early in the season. Leave the rest to fuel continued root development.

Year 3 and beyond: Pull stalks when they reach 12-18 inches and feel firm. Grip each stalk close to the base and pull with a slight twisting motion rather than cutting, which removes it cleanly without damaging the crown. A healthy mature plant can sustain 6-8 weeks of regular harvest.

When to stop: End your harvest by early-to-mid summer. The clearest signal is stalk diameter: once the new stalks coming in are noticeably thinner than what you picked at peak season, stop. Continuing past this point weakens the crown and reduces next season’s productivity.

Zone 7-8 note: In warmer zones, the harvest window is shorter because summer heat arrives earlier. Gardeners in zones 7b-8 often see stalks ready to pull by late April and should plan to stop harvesting by late May to avoid stressing the plant through the long, warm summer ahead.