Kohlrabi

Kohlrabi is technically not a root crop at all, despite living on this site's roots list alongside carrots and beets - the swollen, edible bulb sits above the soil surface, formed from thickened stem tissue rather than a true underground root, which is immediately obvious the first time you actually see a mature plant growing and often genuinely surprising to anyone who's only ever encountered the vegetable pre-cut and bagged in a grocery store.

A Bulb, Not a Root - Why This Matters for Growing It

Because the edible part forms above ground rather than swelling underground the way a beet or turnip does, kohlrabi doesn't share those crops' sensitivity to soil texture or stone content - it grows acceptably even in soil that would fork or deform a true root crop. What it does need is consistent moisture and steady growth without interruption, since a growth check from drought stress tends to produce a woody, fibrous bulb even if it eventually reaches full size.

Harvest at the Right Size, Not the Biggest Size

Kohlrabi bulbs are best harvested at roughly 2-3 inches across for most varieties - considerably smaller than their maximum possible size - because the texture turns markedly woodier and more fibrous the longer the bulb is left to keep swelling past that point. This is the opposite instinct from most root crops, where bigger is usually assumed to be better, and it's worth checking bulb size regularly rather than waiting for a size that looks impressive.

Fast Enough for Real Succession Planting

At only 45-60 days to maturity, kohlrabi is fast enough to fit two full plantings into most growing seasons - an early spring crop and a second late-summer sowing for fall harvest - and like several other quick brassicas on this site, a fall-timed crop that finishes in cooler weather tends to develop better texture and flavor than one that matures into rising early-summer heat.

Companions: A Genuinely Thin Case Either Way

Carrots and kohlrabi share the same root-depth-complementarity logic that applies across several root-crop pairings on this site - a carrot's deep taproot and kohlrabi's above-ground bulb simply aren't competing for the same soil layer, which is useful bed-planning information rather than a documented pest-suppression effect. The one antagonist relationship we track for kohlrabi is with peppers, and it's a comparatively thin case: both are described in some garden references as heavy feeders competing for the same soil nutrients when crowded together, plausible but not something we're aware of being isolated and confirmed in a controlled trial, so we rate it as traditional lore rather than settled.

Purple and Green Varieties

Kohlrabi comes in both pale green and deep purple-skinned varieties, and the color difference is genuinely only skin-deep - the flesh underneath is a similar pale white-green in both, with essentially no meaningful flavor difference attributable to skin color alone. Purple varieties are sometimes chosen simply for visual contrast in a mixed bed or for how clearly they stand out against green foliage at harvest time.

Eaten Raw More Often Than Cooked

Unlike most of the brassica family, kohlrabi is commonly eaten raw - sliced thin for a salad or eaten out of hand like a crisp, mild apple with a faint cabbage-pepper edge - which makes bulb texture at harvest matter even more than it would for a crop that's always cooked before eating, since raw eating has no chance to soften an overly fibrous, past-prime bulb the way roasting or boiling would.