How to grow rhubarb

Rheum rhabarbarum · Polygonaceae · Vegetable

Rhubarb is a cool-season vegetable in the Polygonaceae family, usually started indoors and set out as transplants. It wants full sun, though it tolerates a little afternoon shade in hot regions and steady, even moisture. From sowing to first pick is about 365–730 days. It is one of the toughest crops here, standing through hard frost and often improving for it.

Grower’s note: A cold-loving perennial that needs winter dormancy - it struggles below about Zone 8. Plant dormant crowns with the bud just at soil level. Only the stalks are edible; the leaves are toxic. Take nothing the first year, a few stalks the second.

Sowing

Sow about 2″ deep, into soil between 55–80°F — germination is quickest near 70°F. It is slow and often erratic to germinate (14–21 days).

Spacing & layout

Give each plant about 36″ along the row with roughly 48″ between rows. On a square-foot grid that is one plant per 4 square feet. Allow at least 18″ of loose, workable soil for the roots. It needs more root room than most containers give and does best in the ground.

Fitting it to your season

Rhubarb is a perennial: you plant it once and it comes back and crops for years, so it does not fit the annual sow-and-harvest cycle. Give it a permanent, well-prepared spot out of the way of yearly digging. It takes one to three seasons to reach a full harvest — take little or nothing the first year while the plant establishes.

Quick facts

When to plant rhubarb

Companions

Common problems

Pests: rhubarb curculio, slugs.

Diseases & disorders: crown rot, leaf spot, ramularia leaf spot.

Same family (Polygonaceae)

Rotate these so they don’t follow each other in the same bed year to year.

Figures are typical home-garden ranges from Cooperative Extension planting guides, cross-checked against multiple state sources. Your variety and conditions will vary.