Quantcast
Rhubarb: Planting, Growing, and Harvesting Rhubarb | The Old Farmer's Almanac

Order Your Almanac Today!

Rhubarb

Botanical Name
Rheum rhabarbarum
Plant Type
Vegetable
Sun Exposure
Full Sun
Part Sun
Soil pH
Neutral to Slightly Alkaline
Slightly Acidic to Neutral
Hardiness Zone
3
4
5
6
7
8
No content available.

Planting, Growing, and Harvesting Rhubarb

Catherine Boeckmann
May 26, 2023
Print Friendly and PDF

What grows for 10 years or more, suffers from almost no pests, and is refreshingly easy to care for? It’s rhubarb! This perennial vegetable has tart-flavored ruby or green stems used to make pies, crumbles, jams, and sauces. Learn how to plant, grow, and pick rhubarb properly.

About Rhubarb

Rhubarb originally came from Asia. It was brought to Europe in the 1600s and to America not long thereafter. It thrives in areas with a cooler climate, making it popular in northern gardens. Rhubarb is easy to grow, but needs a dormancy period to really thrive and produce an abundance of huge stalks. Rhubarb does best where the average temperature falls below 40ºF (4°C) in the winter and below 75ºF (24°C) in the summer.

The stalks are the only edible part of the rhubarb plant. These have a rich, tart flavor when cooked. The leaves of the rhubarb plant are toxic. They contain an irritant called oxalic acid, so be sure that they are not ingested.

What’s wonderful about rhubarb is that it’s a perennial: A healthy plant will remain productive for 10 years or more. For that reason, rhubarb should be planted in its own space in any corner of the garden where it can grow undisturbed. Rhubarb grows well in soil amended with plenty of well-rotted manure or compost; this has inspired some gardeners to just go ahead and plant it near their compost piles!

With its ruby or green stems and umbrella-like leaves, rhubarb also adds height and structure to your garden, along with a splash of gorgeous color that will return year in and year out. 

Read Next

Planting

Rhubarb grows best in full sun, but will tolerate partial shade.

Choose a site with soil that is well-draining and fertile. Good drainage is essential, as rhubarb will rot if kept too wet. Mix compost, rotted manure, or anything high in organic matter into the soil. Rhubarb plants are heavy feeders and need this organic matter. Learn more about soil amendments and preparing soil for planting.

Rhubarb gets big! It can grow to 2 to 3 feet tall and wide. Make sure you choose a site where it won’t be crowded. 

When to Plant Rhubarb

  • Rhubarb can be planted in late fall or in early spring.
    • In fall, plant rhubarb crowns after dormancy has set in, and you’ll have rhubarb cropping in the spring!
    • In spring, plant crowns as soon as the soil is workable, when the roots are still dormant, and before growth begins (or as plants are just beginning to leaf out). If you have a temperature gauge, soil temperature should be 50°F minimum.

Spacing for Rhubarb

How to Plant Rhubarb

  • Plant 1-year-old rhubarb crowns, which you can find at a garden center, nursery, or order online. Plants will be sold as bare-rooted specimens or young plants already growing in pots, ready for transplanting. (Rhubarb can be grown from seed, but this is not recommended.)
  • Before planting, eliminate all perennial weeds in the planting site.
  • Dig large, bushel-basket–size holes.
  • Space rhubarb plants about 2 to 4 feet apart and 3 to 4 feet between rows.
  • Plant crowns so the eyes are about 2 inches below the soil surface with buds facing up.
  • Water well at the time of planting.

Check out this video to learn more about how to plant rhubarb:

Growing

Overcrowding is a common problem with rhubarb and can lead to subpar growth. Dig and split rhubarb roots every 3 to 4 years. Divide when plants are dormant in early spring (or late fall). Divisions should have at least one large bud on them. 

  • Mulch generously with a heavy layer of straw to retain moisture and discourage weeds.
  • Water your plant well and consistently. Rhubarb needs sufficient moisture, especially during the hot, dry days of summer. 
  • Remove seed stalks as soon as they appear, as they will only drain energy from the plant that could otherwise be used for producing stalks or roots.
  • Each spring, apply a light sprinkling of a fertilizer (10-10-10) when the ground is thawing or has just thawed. See your local frost dates.
  • In the fall, remove all plant debris. Once your ground freezes, it’s best to cover rhubarb with 2 to 4 inches of organic mulch, preferably well-rotted compost. By adding nitrogen to the soil, you’re preparing the rhubarb plants for a good spring season.

Rhubarb leaf

Recommended Varieties

These common varieties have attractive red stalks and excellent growers: 

  • ‘Canada Red’
  • ‘Crimson Red’
  • ‘MacDonald’
  • ‘Valentine’

In addition to the previous four, there is a reliable, green-stalked cultivar named:

  • ‘Victoria’
Harvesting

Do NOT harvest any stalks during the first growing season. Harvest sparingly in the second year. This allows your plants to become properly established.

  • After a plant’s third year, the harvest period runs 8 to 10 weeks long, lasting through mid-summer.
  • Harvest stalks when they are 12 to 18 inches long and at least 3/4-inch in diameter. If the stalks become thin, stop harvesting; this means the plant’s food reserves are low.
  • Grab the base of the stalk and pull it away from the plant with a gentle twist. If this doesn’t work, you can cut the stalk at the base with a sharp knife. To prevent the spread of disease, be sure to sanitize the knife before cutting. Discard the leaves.
  • Always leave at least 2 stalks per plant to ensure continued production. You may have a bountiful harvest for well over 10 years without having to replace your rhubarb plants.
  • It was once believed that the entire rhubarb plant becomes toxic as summer temperatures rose. This isn’t true, although summer-harvested stalks usually have a tougher texture than those picked in the spring. Nevertheless, after mid-summer (July), it’s best to leave stalks on the plant to allow them to gather energy for next year’s growth.

How to Store Rhubarb

Cut the rhubarb stalks and refrigerate in a covered container. Or, tightly wrap stalks in plastic or aluminum foil and refrigerate. Rhubarb can be kept fresh in the refrigerator for a couple of weeks.

Cut rhubarb stalks in pieces and place in a covered container or zip-type plastic bag, and put in freezer. Frozen rhubarb will last about a year.

Wit and Wisdom

Rhubarb has many other uses, from medicinal to cosmetic. See how to naturally lighten your hair with rhubarb. 

Pests/Diseases

Pests and diseases are rarely an issue with rhubarb, but they may be affected by the following problems.

Rhubarb Pests and Diseases
Pest/DiseaseTypeSymptomsControl/Prevention
Botrytis (gray mold)FungusVaries; yellow/ brown/gray spots with water-soaked margins on leaves/flowers; gray mold; buds remain closed; stem lesions; wilt/rot; scorched appearance (“fire”) in some plantsDestroy infected parts/severely infected plants (do not compost); remove plant debris regularly; disinfect tools; good air circulation/sunlight; avoid overhead watering; prevent plant stress/injury; weed; rotation
Fungal leaf spotFungusVaries; leaf spots on lower leaves enlarge and turn brown/black; fuzzy growth or pustules in lesions; disease progresses upward; leaves dieDestroy infected leaves/ severely infected plants (do not compost); remove plant debris regularly; disinfect tools; resistant varieties; good air circulation; avoid overhead watering
Phytophthora crown and root rotOomyceteLeaves discolor/ wilt; dieback; oozing cankers near base; reddish brown discoloration of inner bark/wood; roots rot; plants slow-growing/stunted/dieDestroy infected plants and surrounding soil (do
not compost); prune out branch cankers; remove plant debris regularly; plant resistant varieties; prevent plant stress/injury; provide good drainage/do not overwater
Rhubarb curculioInsectWeevil-like beetle that bores into stalks/crowns; notches on stalks/leaves; holes in stalks leak sap; plants wilt/decayHandpick adults (appear in mid-May); destroy nearby host plants (sunflowers, thistle, dock) in mid-summer (July)
Slugs/snailsMolluskIrregular holes in leaves; slimy secretion on plants/soil; young stems “disappear”Handpick; avoid thick bark mulch; use copper plant collars; avoid overhead watering; lay boards on soil in evening, in morning lift and dispose of pests in hot, soapy water; drown in deep container of 1/2 inch of beer or of sugar water and yeast sunk to ground level; apply 1-inch-wide strip of diatomaceous earth
Recipes
Strawberry-Rhubarb Pie
Blueberry-Rhubarb Jam
Rhubarb Upside-Down Cake
Cooking Notes

Check out our list of best rhubarb recipes to put your fresh rhubarb to good use! Plus, learn how to make a rhubarb tonic.

Gardening
Vegetables

More Like This

Comments

Jeanette M. Bennett (not verified)

1 week 4 days ago

I had more rhubarb than I knew what to do with, but then I ran into this Rhubarb Jam recipe. It is SO good.
https://pomonapectin.com/rhubarb-jam/

Charlie Huth (not verified)

2 weeks 2 days ago

Excellent article.
Have been trying to locate Riverside Giant rhubarb for last 3 years with no success. Only suppliers found were in Canada and England but neither will ship to the US!

We’ve taken this variety off our list; in some areas, it’s invasive. And it’s just not readily available any more, nor a variety that we recommend.

Denise T (not verified)

2 weeks 5 days ago

I planted a couple of roots about a month ago. The plants are about 8 inches tall and leafing out very well. Today I noticed that the more vigorous one is sending up a middle shoot with numerous small racemes(?). The shoot is only about 4 or 5 inches tall and the buds very small. Is it too soon to remove this stalk or should I wait a little while until it develops more?

Ah, your rhubarb sounds like it’s about to bolt. Yes, CUT it immediately. Do not let the plant go to seed. Using pruning shears, cut the flower stalk as close as possible to the main plant at the base. You must remove it as low as possible so there’s no rot (which is a home to slugs and pests and can cause more damage).

Margaret LaDue (not verified)

4 weeks ago

You speak of dividing plant. If I do that can I use the plant the first year or do I have to wait another year?
Enjoyed reading about your family and rhubarb. It is one of my family’s favorite pie so yummy!!!

Hi Margaret,

You want to divide you rhubarb every 3 to 4 years to avoid it from becoming overcrowded. This is best done in the spring once the ground can be worked and before leaves appear. Dividing rhubarb in the spring gives the plant the entire growing season to rebuild roots and root reserves in preparation for winter.

It is recommended to not harvest rhubarb from divided plants the first year because it allows all of the energy produced by the first-year foliage to go back into the root system.

Liane Dudman (not verified)

1 month 4 weeks ago

Rhubarb was the only plant that we grew under our stately Black Walnut.