German Giant Radish is a fast-maturing cool-season crop that defies expectations about radish size. Ready to harvest in just 28 to 30 days, these radishes grow to impressively large proportions, sometimes reaching baseball size, yet remain remarkably crisp, juicy, and mild-flavored even at their maximum dimensions. Hardy in zones 3 through 10, they thrive in full sun and can be succession-planted throughout spring and fall to provide a continuous harvest of tender, sweet roots. This variety is particularly well-suited to gardeners seeking oversized radishes that don't sacrifice texture or taste for their dramatic size.
Photo © True Leaf Market
Growing Conditions
USDA Zone
3-10
Sunlight
Full Sun
Water
Moderate
Soil
Well-drained, Loose, Fertile Loam
Preferred Temp50-75°F
Growth Stats
12 in
Height
6 in
Width
4 in
Spacing
28–30
Days to Harvest
PeriodAnnual
TypeBush
Plant Profile
Sunlight
Full Sun
Water
Moderate
Zones
3-10
Size
12in H x 6in W
Growth
Annual
Care
High
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Highlights
These radishes shatter the common assumption that large radishes turn fibrous and hot. Even at baseball size, German Giant stays crisp and maintains a sweet, mild flavor that makes them delicious eaten fresh or roasted. They're fast enough to mature before summer heat arrives, yet substantial enough to feel like a real harvest. The beautiful red roots and reliable performance across most of North America have earned this variety a dedicated following among gardeners who want something genuinely impressive in their spring and fall gardens.
Common Uses
German Giant Radishes are eaten fresh as garden snacks or sliced into salads, where their crisp texture and mild sweetness shine. They can also be roasted, which brings out deeper flavors in the roots. The flavor is sweetest when harvested in spring or fall, outside of hot summer months.
Growing Timeline
First Bloom
Does Not Bloom
First Harvest
Mid-spring
Last Harvest
Early Fall
Care Instructions
Direct Sow
Direct sow seeds in early spring or early May, as soon as soil can be worked. Plant seeds 1/2 inch deep directly where you want them to grow, spacing rows 6 inches apart. Thin seedlings to 2 to 4 inches apart, depending on how large you want your mature radishes.
Harvesting
Pull German Giant Radishes as soon as they reach an appetizing size, typically when they're marble-sized or larger, up to about baseball size. You don't need to wait for them to reach maximum dimensions; there's a small window when they're at their best, so harvest when the roots feel firm and the skin looks glossy. At any point up to baseball size, they remain crisp and sweet. Flavor is sweetest in spring or fall, so time your harvest outside of the hottest summer months when possible.
Growing Calendar
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Companion Planting
Pests & Diseases
Ecology & Traits
Edible
Scientific Classification
Raphanus L.
Family
Brassicaceae
Genus
Raphanus
Duration
Annual
Growth Habit
Upright
Native Status
L48 (I)AK (I)HI (I)PR (I)CAN (I)GL (I)