What hardiness zones is Brassica rapa 'Scarlet Queen' suitable for?

Brassica rapa 'Scarlet Queen' is a fast-maturing annual root vegetable in the mustard family (Brassicaceae) reaching 10–14 inches (25–35 cm) tall (foliage) and 6–8 inches (15–20 cm) wide in an upright habit with a basal leaf rosette above the swollen root. The cultivar is a Japanese hybrid producing round flattened roots 2–3 inches (5–8 cm) in diameter with vivid scarlet-red skin and crisp pure white flesh. The cross-section shows the scarlet skin against pure white flesh — the visual contrast is one of the principal culinary draws of the cultivar for fresh-eating presentations. Flesh runs tender, mild, and sweet without the strong peppery bite of larger turnip cultivars. Leaves are green with reddish stems, basal rosette habit, edible as cooking greens. Days to maturity run 40–50 from direct sowing — slightly slower than the 38–45 day 'Hakurei' but still among the fastest-cycling root vegetables. Roots become pithy and hollow if left in the ground past 3 inches (8 cm) diameter, so harvest timing relative to root size is the principal quality control point. The cultivar performs in cool weather and bolts in sustained heat above 80°F (27°C); spring and fall sowings produce the highest-quality roots in temperate climates. Not known to be toxic to pets or humans.

Native Range

The species Brassica rapa (turnip group) originated in central Asia and the Mediterranean region. The 'Scarlet Queen' cultivar is a Japanese hybrid developed for the fresh-eating salad-turnip market and is grown commercially in market gardens across the United States, Canada, and Japan.

Suggested Uses

Grown in vegetable gardens, raised beds, container plantings (3+ gallon containers), and market gardens for culinary use across raw sliced presentations (the scarlet-and-white cross-section adds visual contrast to crudité plates, salads, and cheese boards), pickling (the scarlet skin holds color through brining), and light cooking (quick sauté, glazed, or added to stir-fries). The mild sweet flavor without the peppery bite of larger turnips suits raw eating preparations where pungent traditional turnip flavor would overwhelm. Edible greens are sautéed in olive oil with garlic or added to brassica-greens soups. The cultivar is not suitable for summer growing in hot continental climates where bolting is rapid, and roots do not store for winter use the way longer-keeping turnip varieties such as 'Purple Top White Globe' do.

How to Identify

Habit is upright basal-rosette annual at 10–14 inches (25–35 cm) tall (foliage) and 6–8 inches (15–20 cm) wide. Roots are round flattened 2–3 inches (5–8 cm) in diameter with vivid scarlet-red skin and pure white interior flesh. Leaves are green with reddish stems in a basal rosette. Compared with Brassica rapa 'Hakurei' (white salad turnip), skin runs vivid scarlet-red rather than smooth white, root shape runs flattened rather than globe, days-to-maturity run 40–50 rather than 38–45, and the harvested cross-section shows red-and-white contrast rather than uniform white; compared with 'Tokyo Cross' hybrid turnip, skin runs vivid scarlet-red rather than white and root shape runs flattened rather than round; compared with radishes (Raphanus sativus) of similar red coloring, root size runs 2–3 inches rather than 0.5–1 inch and the flavor runs mild brassica rather than sharp peppery. The vivid scarlet skin combined with the flattened root shape and the red-and-white cross-section identify the cultivar in farmers-market and CSA contexts.

Appearance

Size & Dimensions

Height10" - 1'2"

Width/Spread6" - 8"

Colors

Flower Colors

yellow

Foliage Colors

green

Fall Foliage Colors

no change

Bloom Information

Yellow four-petaled cruciform flowers appear on elongated flowering stalks only when plants bolt in response to sustained heat above 80°F (27°C) or when day length exceeds 14 hours. The cultivar is grown as a cool-season spring and fall crop and is harvested before bolting; bolting plants are pulled and composted as the root has typically become woody and inedible by the time the flowering stalk emerges.

Detailed Descriptions

Flower Description

Yellow four-petaled cruciform (only when bolting); flowering stalks elongate above the foliage

Foliage Description

Green with reddish stems; basal rosette habit; edible as cooking greens

Growing Conditions

Sun Requirements

Full Sun Partial Shade

Requires 4-8 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 7.0(Neutral)

357912

Soil Types

loam sand

Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

40-50 days from direct sow to harvest

Care & Maintenance

Care Guide

Direct sow seeds 0.25 inch (6 mm) deep in early spring 4–6 weeks before the last frost date, or in late summer (August through September in the Pacific Northwest) for fall harvest. Grow in loose well-drained loam or sandy soil at pH 6.0–7.0. Thin seedlings to 3–4 inches (8–10 cm) apart in rows 12 inches (30 cm) apart when seedlings reach 2 inches (5 cm) tall — thinnings are edible as microgreens. Consistent moisture during root formation produces smooth non-pithy roots; drought-stressed plants run smaller, woodier, and bolt earlier. Days to maturity run 40–50 from direct sowing. Harvest at 2–3 inches (5–8 cm) diameter for the fullest flavor and crispest texture; roots become pithy and hollow within 5–7 days of reaching mature size. The cultivar is cool-season only and bolts in sustained summer heat — successive sowings every 2–3 weeks across the cool-weather window extend the harvest rather than relying on a single planting. In the Pacific Northwest, fall sowings (August–September) produce the sweetest roots as cooling autumn temperatures increase root sugar content.

Pruning

No horticultural pruning applies. Plants are harvested whole by pulling the root with the foliage attached. Greens are sparingly harvested from growing plants — outer leaves are cut while the central growing point continues developing the root. The cultivar does not store well; roots are eaten within 1–2 weeks of harvest rather than placed into root cellar storage.