Watermelon
Citrullus lanatus · vegetable · frost-tender
Watermelon demands long warm seasons and warm soil; direct-seed only after soil passes 70°F. For the seed trade it is a high-stakes crop: bacterial fruit blotch (Acidovorax citrulli) is seed-transmitted, and outbreaks traced to infected seed lots in the late 1980s and 1990s drove the industry-wide seed health testing and grow-out protocols still in place today.
Diseases of watermelon
- seedborne
Bacterial Fruit Blotch
Acidovorax citrulli
- nematode
Root-Knot Nematode
Meloidogyne spp. · codes: N
- oomycete
Phytophthora Blight
Phytophthora capsici · codes: Pc
Planting watermelon
Windows are computed per location from median frost dates. Pick a place on the Grow pages for exact dates; the rules by climate band:
| Zone band | Method | Timing |
|---|---|---|
| temperate | direct sow | 14-35 days after last frost, soil ≥ 70°F |
| cool | indoor start | 14-28 days before last frost, Short-season areas: start in pots 2-4 weeks before last frost; cucurbits resent root disturbance. |
| cool | transplant | 14-28 days after last frost, soil ≥ 70°F |
Who breeds & sells watermelon
- American Seed Trade Association
- Bayer Crop Science
- Seminis Vegetable Seeds
- Syngenta Vegetable Seeds
- BASF | Nunhems
- W. Atlee Burpee & Co.
- Baker Creek Heirloom Seed Co.
- Eurofins BioDiagnostics
Research touching watermelon
Related crops: Melon · Cucumber · Tomato
Sources & References
Evidence: 1 source, all independent references.
- Cucurbit Production Guides · University of Florida IFAS Extension, University or Government