Plant rhubarb crowns or divisions in early spring while they are still dormant, as soon as the soil can be worked. In northern Utah that is late March to mid-April (Utah State), and Illinois and Ohio State both plant in early spring. Ohio State says a fall planting after the plants go dormant also works. Then wait: no harvest the first year, a light picking in year two, and full harvests from year three (Illinois).
Rhubarb is a perennial. One planting can produce for 10 to 15 years or more (Utah State, UMN), so the planting date matters less than the spot you choose and your patience for the first two seasons. It also needs cold: Ohio State says it grows best where winters drop below 40°F to break dormancy and summers average under 75°F.
Spring planting dates by last frost
The table counts back from your average last spring frost. The crown window is GardenPal's translation of Utah State's late March to mid-April window for northern Utah, which runs from about 6 weeks to 2 weeks before the frost there. Growing from seed is slower: UMN and Illinois start seeds indoors about 6 weeks before the last frost, and UMN hardens the seedlings off for at least a week before setting them out.
| Average last spring frost | Plant dormant crowns or divisions | Or start seeds indoors | Set out seedlings |
|---|---|---|---|
| Mar 1 | Jan 18 – Feb 15 | Jan 18 | Mar 8 – Mar 22 |
| Mar 15 | Feb 1 – Mar 1 | Feb 1 | Mar 22 – Apr 5 |
| Apr 1 | Feb 18 – Mar 18 | Feb 18 | Apr 8 – Apr 22 |
| Apr 15 | Mar 4 – Apr 1 | Mar 4 | Apr 22 – May 6 |
| May 1 | Mar 20 – Apr 17 | Mar 20 | May 8 – May 22 |
| May 15 | Apr 3 – May 1 | Apr 3 | May 22 – Jun 5 |
| Jun 1 | Apr 20 – May 18 | Apr 20 | Jun 8 – Jun 22 |
Illinois doesn't recommend sowing rhubarb seed straight into the garden except in the extreme South, and seedlings don't always look like the parent variety, so most gardeners buy crowns or divide a friend's plant. Utah State lists 'Canada Red', 'Crimson Red' and 'Victoria' among common varieties.
How to plant rhubarb
Because a rhubarb plant stays for years, put it at the edge of the garden where it won't be disturbed when you work the annual beds (UMN). Give it full sun and well-drained soil; UMN digs the bed about 2 feet deep and mixes in compost.
| Step | What extension sources say |
|---|---|
| Depth | No more than 1 inch of soil over the bud (Utah State); 1 to 2 inches over the crown (Ohio State); crown buds about 2 inches below the surface (Illinois); bare-root crowns level with the soil and potted plants at pot depth (UMN). Planting too deep delays the plant or kills it (Utah State). |
| Spacing | About 3 feet apart in rows 4 feet apart (Utah State); 36 to 48 inches apart, rows 3 to 4 feet (Illinois); roughly 3 by 3 feet per plant (UMN) |
| Drainage | Crowns rot in wet soil; Illinois suggests raised beds where drainage is poor |
| Water | About 1 inch a week (UMN) |
| Feeding | Illinois fertilizes before spring growth starts |
| Seed stalks | Cut off flower stalks as they appear so the plant puts its energy into leaves (UMN) |
When you can harvest
The first two years build the root. Harvesting too soon weakens the plant, so the extension sources agree on a slow start:
| Season after planting crowns | Harvest |
|---|---|
| Year 1 | None (Illinois, Ohio State, UMN) |
| Year 2 | A light picking for 1 to 2 weeks (Illinois) or a few stalks (Ohio State). Utah State waits until year 3. |
| Year 3 and after | 8 to 10 weeks (Illinois); Utah State starts with 3 to 4 weeks in year 3 and 6 to 10 weeks from year 4 |
Plants grown from seed take a year longer (UMN). When you do harvest, pull and twist each stalk from the base instead of cutting it (UMN), and leave at least two-thirds of the leaves on the plant (Illinois). UMN stops harvesting at the end of June, and Ohio State harvests from late April through June, so the plant can rebuild for next year. A healthy plant gives about 4 to 12 pounds of stalks a season (Utah State).
Dividing an older plant
Crowded crowns produce thinner stalks. Illinois divides plants after about 5 years, and Utah State every 5 to 10 years. Do it in early spring while the plant is dormant: dig the crown, split it into pieces that each have at least one bud and a good piece of root, and replant them like new crowns. Dividing is also the cheapest way to start a new bed.
Texas, Florida and the Deep South
Rhubarb is a cold-climate crop. Mississippi State says it isn't adapted to Mississippi, where hot summers, wet winters and heavy clay work against it, and that it does best where summers stay under 75°F. The Texas A&M and UF/IFAS planting guides we use don't list it. If you try it in a warm area, Mississippi State suggests a well-drained raised bed with light shade, and expect smaller harvests and shorter-lived plants than in the North.
Where rhubarb goes in the garden
Rhubarb shares the permanent edge of the garden with other perennials. What to plant with asparagus covers planning a long-term bed, and when to plant strawberries covers another perennial for the same corner.
Frequently asked questions
When should I plant rhubarb?
In early spring while the crowns are still dormant, as soon as the soil can be worked; in northern Utah that is late March to mid-April (Utah State). Ohio State says fall planting after the plants go dormant also works.
Can you plant rhubarb in the fall?
Yes. Ohio State says rhubarb can be planted in fall once the plants are dormant, as well as in early spring. Mulch the crowns with straw after the ground freezes.
How deep do you plant rhubarb crowns?
Shallow. Utah State puts no more than 1 inch of soil over the bud, and Ohio State 1 to 2 inches over the crown. Planting too deep delays growth or kills the plant.
When can I harvest rhubarb after planting?
Not in the first year. Illinois picks lightly for 1 to 2 weeks in year two and harvests for 8 to 10 weeks from year three; Utah State waits until year three. Plants started from seed take a year longer (UMN).
Can you grow rhubarb from seed?
Yes, but it is slower and seedlings may not match the parent. Start seeds indoors about 6 weeks before the last frost (UMN, Illinois) and wait an extra year before harvesting.
Does rhubarb grow in Texas or Florida?
It struggles. Rhubarb needs winters below 40°F and summers averaging under 75°F (Ohio State), and Mississippi State says it isn't adapted to the hot, humid South. A raised bed with light shade is the best bet if you try it.
Are rhubarb leaves poisonous?
Yes. Extension sources including UMN warn that the leaves are toxic, so eat only the stalks and compost the leaves.
Enter your frost dates to see when strawberries, asparagus and the annual crops around your rhubarb can go in.
Open itSources
- Virginia Cooperative Extension, "Companion Planting in Gardening" (SPES-620P)
- University of Maryland Extension, "Vegetable Succession and Companion Planting"
- Oregon State University Extension, "Companion Planting"
- Penn State Extension, "Herbs Make Good Plant Partners and Companions"
- University of Minnesota Extension, "Planting the vegetable garden"
- USDA Plant Hardiness Zone Map
- NOAA NCEI U.S. Climate Normals (frost/freeze data)
- University of Minnesota Extension, "Growing rhubarb"
- University of Illinois Extension, "Rhubarb" (home vegetable gardening)
- Utah State University Extension, "Rhubarb in the Garden"
- Ohio State University Extension, "Growing Rhubarb in the Home Garden"
- Mississippi State University Extension, "Rhubarb"
Pairings are summarized in our own words from extension-service guidance. Research support for many companion effects is limited, so treat them as good habits, not guarantees.