Long Black

Radish

55d to harvest

Sink your senses into Long Black’s velvety, inky skin—an elegant black radish that feels almost lacquered in the hand. Beneath the dark exterior lies crisp, bright flesh with a clean, peppery snap that mellows beautifully when allowed to reach full size at about 55 days. Ideal for bold fresh slices and striking grated accents, Long Black also shines in quick pickling for a dramatic color contrast and lively bite.

Crop Dates

Growing note: In frost-free Zone 12b, grow this cool-season crop during the cooler dry season (October–February).

Milestone	Date
Start Indoors	—
Climate	Frost-Free Climate
Transplant / Sow Outdoors	Oct 1st
Harvest Begins	Nov 25th
Harvest Ends	Feb 28th

Crop Details

Trait	Value
Days to Maturity	55
Sun Requirements	Full Sun
Growth Habit	Taproot
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	60
Min Soil Temp (°F)	45
Min Night Temp (°F)	28
Harden Off (days)	Not Required

Frequently Asked Questions

What pest or disease most often affects radish (Raphanus sativus) like Long Black, and what should I do?

For Raphanus sativus, flea beetles commonly cause small shot-hole damage on leaves, especially in warm weather. Cover seedlings with a fine mesh row cover until plants are well established, and hand-remove heavily damaged foliage to slow spread. If you see fungal leaf spots or a grayish mold from overly wet conditions, water at the soil line and improve spacing for airflow.

How often should I water Long Black radishes during their main growth phase to form a good root?

During root bulking (roughly weeks 3–6), keep the soil evenly moist but not soggy—about 1 inch of water per week total, adjusted for heat and rainfall. Water deeply when the top 1 inch of soil starts to dry, since radishes that swing between dry and wet can become woody or cracked. Mulch lightly to reduce moisture swings while avoiding a thick layer that stays wet.

How can I tell when Long Black radish (Raphanus sativus) is ready to harvest?

Harvest around 55 days, but confirm by checking the shoulder of the root at the soil surface. When the root is firm and roughly 1.5–2.5 inches wide (and the skin looks fully colored), pull it before it gets hollow or pithy. If you see the leaves fading and the root feels overly firm/woody, harvest immediately to preserve eating quality.