Purple Plum

Radish

28d to harvest

Sweetly peppery and vividly crisp, Purple Plum radish brings a jewel-toned crunch to the garden—its skin is a deep plum-purple that fades to a clean, tender white at the tip. At just 28 days, roots stay pleasantly slender and snappy, delivering a fresh, juicy bite that shines in salad mixes and bright garnishes. Grow a small stand for quick harvests and enjoy the striking color that makes every platter look freshly picked.

Crop Dates

Growing note: In frost-free Zone 12a, 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	Oct 29th
Harvest Ends	Feb 28th

Crop Details

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

Frequently Asked Questions

How do I manage common pests or diseases on Raphanus sativus (purple plum radish) in my garden?

Watch for flea beetles, which can leave small shot-holes in radish leaves and reduce root growth—use floating row cover from sowing until harvest and handpick heavily damaged plants. If you see pale, stippled leaves or silvery scarring, target thrips with insecticidal soap, applied in the cool morning, and remove badly infested leaves. For disease, avoid wet foliage and rotate beds, since overcrowded, damp conditions increase the risk of downy mildew and other leaf spotting that can affect yield.

How often should I water purple plum radish during the main growing phase?

Water so the soil stays evenly moist to a depth of about 6 inches, especially from germination through root bulking (roughly the first 2–4 weeks). In most home gardens this means about 1 inch per week total, split into 1–2 waterings, but adjust to weather so the top inch of soil never dries out completely. If the soil swings between dry and soggy, radishes are more likely to become pithy or overly hot.

How can I tell when purple plum radish (Raphanus sativus) is ready to harvest?

Harvest when the roots have filled out—typically about 28 days after sowing—and when the shoulder of the radish is clearly visible above the soil. For best eating, pull radishes as soon as they reach a thumbnail-to-dime sized diameter, because they become woody and can turn strong-flavored if left in the ground. If you want a milder radish, start checking from day 25 and harvest the earliest ones first.