Celeriac, kohlrabi, horseradish and Jerusalem artichokes can all work in West Virginia, but the frost calendar is only half the answer. At Charleston the last spring freeze falls between April 9 and April 23, and these crops care more about warm soil than warm air. Elevation changes the numbers a lot. The valley dates below are the generous end of what the state offers.
When the soil is warm enough in West Virginia
NOAA’s 1991-2020 Climate Normals put the last spring 32°F freeze at Charleston between April 9 and April 23 (station USW00013866, the 30-70% probability band). That is a probability, not a promise, and a late cold snap can still land outside it. Charleston is also a river valley. Hillside and mountain gardens run colder, so treat the valley dates as the early edge of the state’s range.
Frost is a proxy here. Celeriac, kohlrabi, horseradish and Jerusalem artichokes, the four crops covered in Celeriac, Kohlrabi, Horseradish and Jerusalem Artichokes, are waiting on soil temperature, and soil warms after the frost risk ends, not at the same moment. A bed can be frost-free by mid-April and still be cold and wet a few inches down. Seed or tubers sitting in that chill rot, stall, or sprout unevenly.
A cheap soil thermometer, pushed a few inches deep and read in the morning, beats any date. This page has no verified soil-temperature thresholds for West Virginia, so ask West Virginia University Extension for the numbers they recommend. They know your county’s soils, which a statewide article cannot.
The crops differ in how long they will wait. Kohlrabi is a cool-season brassica and tolerates chilly soil better than the others, so it goes in first. Celeriac is the long-season one. It is normally started indoors weeks ahead and set out only once the frost risk has passed and the ground has warmed. Horseradish is planted as root pieces and Jerusalem artichokes as tubers, both as soon as the soil can be worked and has begun to warm.
Site the Jerusalem artichoke before you plant it
Jerusalem artichoke is effectively permanent once planted. Every fragment of tuber left in the ground regrows, and digging the patch only scatters more pieces. It is probably the most regretted planting in a vegetable garden. Give it a dedicated corner, away from the beds you rotate, bordered by a mown strip, a lawn edge or a hard barrier. Assume you are choosing its spot for good. Horseradish behaves much the same way, because a leftover scrap of root will sprout. Put it somewhere you can live with it.
How long the season lasts here
The same NOAA normals put the first fall freeze at Charleston between October 18 and November 1. Pair those dates with the spring ones and the frost-free window runs from 178 days (April 23 to October 18) to 206 days (April 9 to November 1). That is roughly 25 to 29 weeks, depending on which edge of each band the year lands on. Because the fall caution applies, a garden on higher ground will see the autumn end of that window arrive sooner.
What does a window that size allow? A second sowing, for one thing. At the long end, a fast crop like kohlrabi can be sown in spring, harvested, and followed by a second sowing in midsummer to mature in the cooler weeks of fall. Fall-grown brassica roots often taste better for the cool nights. The succession sowing guide on this site lays out how to stagger those plantings, and it applies directly here.
A shorter window changes the arithmetic. Where fall freezes come early, as in the mountains, the first sowing is the only one, and every week lost to cold soil comes off the end. That makes transplanting for celeriac and kohlrabi more attractive, since you buy back weeks indoors. But transplanting costs something too. Roots resent disturbance, so check each seedling’s root ball before setting it out. A pot-bound or tangled start tends to produce a poorly shaped root, and a crop grown for its root cannot afford that.
For celeriac the window is the whole question. It is the longest-season crop of the group, and a gardener in a Charleston-type valley has room to finish it. On a ridge with a short run between frosts, the margin is much thinner. Horseradish and Jerusalem artichokes are largely indifferent to the length of one season, since they live on from year to year and bulk up over many months.
For a comparison with other climates, Growing Unusual Root Crops in Kentucky and Growing Unusual Root Crops in Missouri show how the same crops adjust to different seasons and soils.
Heat and water in West Virginia
Two figures would normally anchor this section: the count of days above 90°F and the summer rainfall total. This page does not carry verified versions of either for West Virginia, and an invented number would be worse than none. Your nearest NOAA climate-normals station and WVU Extension can supply both for your area. Whether a given summer runs hot and dry or cool and damp, the roots tell on it. Uneven watering during a dry spell gives celeriac and kohlrabi splits, woody texture and hollow cores. A damp summer brings foliage disease, mildew, slow ripening and rot at the crown. Both problems have the same remedies: steady moisture, a mulch layer to shade the soil, and spacing that lets air move through the foliage.
Two facts that this page does hold govern the group. The first is season length, which I covered above. It decides whether celeriac can finish here at all. The second is the winter low. The mean daily minimum of the coldest month at Charleston is 26.1°F (NOAA NCEI Climate Normals 1991-2020). That is an average, not a record low, but it shows that nights below freezing are the norm in midwinter, not the exception.
The USDA Plant Hardiness Zone Map (2023, based on 1991-2020 normals) places West Virginia in zones 5a to 7a. That is a wide statewide range, and the reference city is only one point in it. High, cold ground sits near the 5a end and sheltered valleys near the other. The practical question is whether the ground freezes hard enough to damage what you leave in it.
Horseradish and Jerusalem artichokes are hardy perennials, generally rated for colder climates than this state, and they can stay put under a layer of mulch. Dig them as needed. Celeriac and kohlrabi are another matter. A hard freeze can damage them, so lift them before the soil freezes and store them. Stored roots need inspection, not faith. Check them regularly. A soft patch, a weeping spot or a moldy crown ends the question for that root, whatever the rest of it looks like. A root that looks sound is not thereby safe to eat, so discard anything suspect and do not trim around it.
Which these root crops suit West Virginia
This page does not name varieties, and that is deliberate. A cultivar recommendation only means something if it has been trialled where you garden, and West Virginia ranges from river valleys to ridgetop gardens with very different seasons. The varieties that perform locally are documented by West Virginia University Extension, so start there. Any name offered here without that source would be a guess dressed as advice.
What I can offer is the type of choice to make, reasoned from the facts above. Where the season is short, favor the earliest types: quick-maturing kohlrabi, and for celeriac, the earliest-maturing types you can find, or skip it. Where summers are hot, favor types that tolerate warmth and give them mulch and some afternoon shade at the root. Where summers are humid, make disease resistance your first filter, because damp foliage and crowded rows are where the trouble starts.
Kohlrabi is a brassica, as are turnips and rutabagas. They share their pests and diseases with cabbage, kale and mustard, so rotating kohlrabi into a bed that grew cabbage last year rotates nothing. The crop rotation guide on this site explains how to space them out.
Horseradish suits nearly the whole state, given its hardiness and its willingness to grow anywhere. When you prepare it, remember that grating a fresh root releases compounds that burn the eyes and airways. Work with the windows open or a fan running, keep your face away from the bowl, and don’t treat it as a joke.
Jerusalem artichokes also suit the state. They store inulin instead of starch, and many people get digestive discomfort from them. A small first portion is the sensible way to find out how you react. Plant them only where you are content to see them for years.
Common questions
Can I plant these roots before the last frost date?
Kohlrabi tolerates cool soil and can go in early. Horseradish and Jerusalem artichokes can be planted once the soil is workable. Celeriac should wait until the frost risk has passed and the ground has warmed.
Will horseradish and Jerusalem artichokes survive a West Virginia winter?
Both are generally hardy to colder zones than the 5a to 7a range USDA gives the state, so they can usually stay in the ground under mulch. If you lift them for any reason, expect regrowth from leftover pieces.
Is celeriac realistic at higher elevations?
It is the riskiest of the four. Higher ground freezes earlier in fall than Charleston’s October 18 to November 1 band, and celeriac needs the longest run. Ask local extension staff before committing bed space.
Where do I find varieties proven in West Virginia?
West Virginia University Extension is the place to ask. County offices can tell you what has been trialled nearby, and that is worth more than any variety list that has not been tested in your own soil.