Pull spring-sown beets 60 to 80 days after seeding. In Wisconsin that means roughly late May into early July for rows sown in the two to three weeks before the last frost. Fall roots should be out before the freeze reaches your garden. The surprise comes after harvest: topped beets keep best at 33 to 36°F, and the 32 to 34°F range that suits most root crops produces more black spot and rot. Beets are sown in place, so the clock starts at seeding.
The short answer
Antigo ground, and what a beet makes of it
Wisconsin’s official state soil is the Antigo series, an Alfisol: a forest soil of moderate fertility that holds nutrients reasonably well. USDA NRCS Soil Data Access gives representative surface values, drawn from 65 mapped components, of 20 percent sand, 10 percent clay and 70 percent silt, which makes it a loam to silt. Organic matter is about 3.0 percent, surface pH about 5.5 (slightly acid), and drainage is well drained.
Utah State University Extension, in “Beets in the Garden,” says beets want deep, sandy, well-drained soil rich in organic matter, amended with no more than 1 inch of composted organic matter per 100 sq ft. Antigo passes on drainage. It falls short on sand. With 70 percent silt it holds more water than a sandy bed would, which cushions a dry week. Silty surfaces can also seal over after a hard rain, and a crust is hard on a beet seedling.
Treat all of this as a starting point, not a diagnosis. A state spans hundreds of soil series, and river bottoms, hill country and any lot a builder has scraped or filled will differ completely. These figures describe a mapped surface layer, not a worked bed, and the pH is not yours. A soil test gives you your own number, and Beet Soil in Wisconsin: What the Root Will Meet covers what to do with it.
Heat and the woody root
A count of days per year above 90°F is not published in the data behind this page, so I won’t guess one. The threshold Utah State names is lower anyway: heat above 85°F combined with water stress makes the root woody. That failure belongs to the late weeks, when the root is sizing up.
It is a different problem from bolting, which comes from water stress in the first six weeks. A beet that went thirsty in week three flowers early. One that got hot and dry in week ten turns woody. “Keep it watered” doesn’t cover either failure on its own.
So the practical answer is to pull at the 60 to 80 day mark, once the roots are the size you want, rather than letting them sit through the first hot stretch. Twist or cut the tops off right away. The Growing Beets in Wisconsin guide covers the season around that harvest.
The six weeks that decide it here
Where the dates land
The last spring frost in the NOAA NCEI climate normals falls between April 16 and April 29. That range is the 30 to 70 percent band of 32°F freeze probabilities at station USW00014839. Sowing 2 to 3 weeks ahead of it puts seed in the ground between about March 26 and April 15. At the early end that is more theory than plan, since the soil has to be workable and not sodden. The later end is the safer bet in most years.
Count from the day the seed goes in. Beets are never transplanted, so 60 to 80 days run from seeding. Add that to the sowing window and the first roots are ready around the end of May, and the last of the spring row by early July. The first six weeks, the stretch that decides bolting, end somewhere between early May for the earliest sowing and late May for the latest.
Where the bolting risk sits
Wisconsin springs swing. Cold, wet weeks off the snowmelt give way to warm, dry spells, often within days. The frost data above carry no rainfall, so read this as a pattern, not a forecast. The bolting risk sits in the dry swing. A bed sown in mid-April that goes two weeks without rain in mid-May is squarely inside the six-week window, and water stress there is what triggers premature flowering.
The soil softens this a little and not entirely. Silt holds moisture below the surface, but the seedbed at the top dries first, and the seedlings live in that top inch. Even moisture from sowing day matters more than any single heavy soaking.
There is a squeeze built into the calendar. Sow early and the first six weeks run through the swingiest part of spring. Sow late and the roots finish into early July, when heat above 85°F can turn a water-stressed root woody. Neither end of the window is free. If you can only water on a schedule, the middle of the window is the compromise that gives you the best shot at both.
What goes wrong here
Chewed leaves are a separate problem, covered in What Eats Beet in Wisconsin, and When. The failures below come from the ground, the weather and the cold room afterward.
In the bed
- Bolting in a dry spring. Water stress in the first six weeks causes premature flowering. Keep the seedbed evenly moist from sowing day, and break up a surface crust gently before it hardens around seedlings.
- Woody roots in early summer heat. Heat above 85°F with water stress makes the root woody. This is a separate failure from bolting. Pull at the 60 to 80 day mark and water deeply during hot spells instead of leaving roots in to get bigger.
- Too much compost. More than 1 inch of composted organic matter per 100 sq ft goes past what Utah State recommends. Stay under that limit and let a soil test, not the 3.0 percent figure for the state soil, tell you what your bed needs.
- Assuming your pH is 5.5. That number describes the mapped surface of the state soil, not your garden. Test before you add anything to change it.
- Pulling by your neighbor’s calendar. Inland southern Wisconsin typically freezes in early October, the north far earlier, and Lake Michigan delays the first fall freeze along the lakeshore. Lift fall roots on your own local date.
In storage
- Storing them too cold. USDA Agricultural Handbook 66 says that at 32 to 34°F more black spot and rot occur than at higher temperatures. Topped beets belong at 33 to 36°F and 98% relative humidity. In a pit or cellar, stay between 31°F and 41°F, never below or above.
- Leaving the tops on. Bunched beets with leaves last only 10 to 14 days, at 32°F and above 98% relative humidity. Top them first, then store the roots.
- Storing the small ones. Large roots keep much better because they lose water and shrivel more slowly. Keep the big roots for storage and eat the small ones first.
The handbook is the USDA reference on commercial storage, and its numbers are written for commercial rooms. A home cellar or garage will drift more than they do. Check it with a thermometer, not by feel.
Common questions
How many days from seeding until I can pull beets?
Plan on 60 to 80 days, counted from the day the seed goes in. Beets are sown in place, so there is no transplant date to count from. The spring row sown between about March 26 and April 15 comes out from late May into early July.
Is the Antigo soil the soil in my garden?
Probably not exactly. Antigo is the state soil, with 20 percent sand, 10 percent clay and 70 percent silt at the surface, but Wisconsin has hundreds of soil series. Use it as a sense of what the region’s ground tends to do, which is drain well and hold some water. Then get a soil test for your own bed.
What temperature should I store beets at, and what do I do first?
Top them, then hold the roots at 33 to 36°F and 98% relative humidity. Colder is not better here, because 32 to 34°F brings more black spot and rot. Keep the large roots for storage and eat the small ones first, since small roots shrivel faster.
Does the first fall freeze arrive on the same date across Wisconsin?
No. Inland southern Wisconsin typically freezes in early October, and the north freezes far earlier. Lake Michigan delays the first fall freeze at the lakeshore. The NOAA NCEI figures on this page cover the last spring frost only, so exact fall dates for your county are not published here.