How to Grow Crimson Sweet Watermelon
Citrullus lanatus var. lanatus
Crimson Sweet Watermelon is a beloved heirloom melon prized for its vibrant red flesh and sweet flavor. Gardeners grow this warm-season crop to enjoy refreshing summer fruits that thrive in full sun and rich, well-drained soil.
📷 Wikimedia CommonsStarting Crimson Sweet Watermelon: indoors or direct sow?
🌾 Sow directly in the garden — Crimson Sweet Watermelon is not usually started indoors.
Direct sow seeds outdoors only after all danger of frost has passed and soil temperatures have warmed sufficiently for germination.
Soil, care & harvest
Prepare loose, fertile soil with a pH between 6.0 and 7.0 before sowing. As a frost-sensitive warm-season crop, you must wait until after the last spring frost when the ground is thoroughly warm to plant directly outdoors. Do not start indoors; simply scatter seeds about one inch deep in rows or hills. Expect germination within seven to ten days under these ideal conditions.
Space plants four to six feet apart to allow vines ample room to spread without crowding. Water deeply one to two inches per week, ensuring moisture reaches the roots while avoiding overhead sprinkling during fruit development. Apply organic mulch around the base to retain soil moisture and suppress weeds, feeding lightly if growth appears sluggish.
Watch for cucumber beetles, squash vine borers, aphids, and thrips; use row covers early or apply insecticidal soap as needed. Prevent powdery mildew, bacterial fruit blotch, and gummy stem blight by ensuring good air circulation and avoiding wetting the foliage. Harvest fruits approximately eighty-five days after planting when they develop a deep golden rind.
When to Plant Crimson Sweet Watermelon
Planting windows vary by USDA hardiness zone. Look up yours by ZIP code.
| Zone | Start Indoors | Direct Sow | Harvest |
|---|---|---|---|
| Zone 1 | June | July – September | October – August |
| Zone 2 | May – June | July – August | October – September |
| Zone 3 | May | June – August | September – October |
| Zone 4 | April – May | June – July | September – October |
| Zone 5 | April | May – July | September – October |
| Zone 6 | April | May – July | August – October |
| Zone 7 | March – April | May – June | August – September |
| Zone 8 | March | April – June | July – September |
| Zone 9 | February | March – May | June – August |
| Zone 10 | January – February | March – April | June – July |
| Zone 11 | January | February – March | May – June |
| Zone 12 | January | February – March | May – June |
| Zone 13 | January | February – March | May – June |
Companion Plants for Crimson Sweet Watermelon
✓ Good companions
Fix nitrogen in soil and don't compete for space with sprawling vines
Repels ants, aphids, and cucumber beetles while attracting beneficial insects
Provides vertical structure and wind protection without root competition
Acts as living mulch, conserves soil moisture, and matures before watermelons spread
Deter nematodes and cucumber beetles with their strong scent
Trap crop for cucumber beetles and squash bugs, repels aphids
Deters pests and may enhance watermelon flavor through aromatic compounds
Break up compacted soil and deter cucumber beetles and squash vine borers
✗ Keep away from
Allelopathic properties inhibit growth and development of watermelon plants
Allelopathic compounds suppress watermelon growth and compete heavily for nutrients
Both heavy feeders competing for nutrients, increased disease risk from shared pathogens
Nutrition Facts
Per 100g serving (USDA FoodData Central)
