Raphanus sativus 'Watermelon'
vegetableA heirloom radish with striking green skin and a vivid hot-pink-to-red interior that resembles a watermelon when sliced. Mild flavor with a crisp, juicy texture and pleasant slight bite. The showstopper of any salad or charcuterie board. Larger and slower-maturing than spring radishes, grown as a fall and winter crop for best results.
Sun
full sun
Water
Every 2 days
Harvest
~60 days
Difficulty
easy
Lifecycle
annual
One season, then done
Spacing
4 in
Planting Depth
1/4-1/2 in
Soil pH
6.0-7.0
Soil Type
Loose
Hardiness Zones
Zones 3 – 10
Grown as an annual. This range is its winter hardiness, but you can grow it for a single season in any zone.
When to Fertilize
Light balanced fertilizer at planting; no heavy feeding needed
Fertilizer
Low-nitrogen balanced fertilizer; excess nitrogen produces large tops and small roots
Sow directly in late summer for a fall crop, late July to August in most climates. Watermelon radish is a daikon-type and needs cool temperatures for the best color and flavor. Spring-sown radishes tend to bolt before developing good roots. Thin to 4 inches. Allow 50 to 70 days to mature. The exterior stays green even when fully ripe. Judge by size (2 to 3 inches in diameter).
spring planting
Direct sow
Apr 1
Projected first harvest
May 31
fall planting
Direct sow
Aug 4
Projected first harvest
Oct 3
Good neighbors that attract beneficial insects or deter pests
Proactive ways to stop trouble before it starts. Tap a name with an arrow for its full guide
Row cover from sowing; diatomaceous earth; succession planting
Row cover; avoid fresh manure before planting; rotate location
Water blast; insecticidal soap; allium companion plants
Rotate with non-brassica crops; lime soil if clubroot is present in the area
Harvest when roots reach 2 to 3 inches in diameter, about 50 to 70 days from sowing. The green exterior gives no ripeness cue, so check size by gently brushing soil aside. Overripe roots become pithy and lose crispness. Wash thoroughly, then slice into rounds or quarters to reveal the dramatic pink interior. Refrigerate and use within 2 to 3 weeks.
Good source of vitamin C, folate, and potassium. The striking pink interior is caused by anthocyanins with antioxidant properties. Contains glucosinolates with cancer-protective activity. High water content and fiber aid digestion. Very low in calories.
For educational and informational purposes only. HomeSown is not medical, health, or other professional advice. Always positively identify any plant before handling or eating it; some plants, and some parts of otherwise-edible plants, are toxic. Consult a qualified professional before consuming or otherwise using any plant, especially if you are pregnant, nursing, taking medication, or have a health condition.
spring planting
fall planting