How to Grow Crimson Sweet Watermelon
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Crimson Sweet Watermelon
Citrullus lanatus 'Crimson Sweet'
fruitCrimson Sweet is a classic, widely-grown watermelon variety prized for its deep red flesh, excellent sweetness, and reliable production. This mid-sized melon typically weighs 15-25 pounds and features dark green skin with lighter green striping. It's one of the most popular home garden and commercial varieties due to its consistent quality and disease resistance.
When should you plant Crimson Sweet Watermelon in your zone?
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Example Crimson Sweet Watermelon timeline · Pittsburgh, PA (Zone 6b)
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Plant Crimson Sweet Watermelon
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Crimson Sweet Watermelon
Around Jul 1≈ 75 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Crimson Sweet Watermelon dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-11; best in zones 5-10 with long, warm growing seasons
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Get my Crimson Sweet Watermelon timeline →Growth Stages
Seedling/Sprouting
7-10 daysSeed germinates and first true leaves emerge. Plant grows slowly at first, establishing root system.
Keep soil consistently moist but not waterlogged. Thin to strongest seedling if direct seeding. Protect from strong wind.
Flowering
2-3 weeksYellow flowers appear on vines (male flowers first, then female flowers with small melon behind). Pollinator activity increases.
Ensure adequate phosphorus and potassium (avoid excess nitrogen). Maintain consistent watering. Attract pollinators with flowers nearby. Hand-pollinate if needed.
Fruit Development & Growth
3-4 weeksFemale flowers set fruit; melons swell rapidly and reach full size. Skin darkens and patterns become distinct. Vines continue spreading.
Water deeply and regularly but reduce frequency slightly to concentrate sugars. Place straw under developing melons to prevent soil contact. Thin to 1-2 best fruits per vine for larger melons.
Maturation & Harvest
1-2 weeksMelons reach full size, skin becomes hard, and flesh develops deep red color and maximum sweetness. Tendrils near fruit stem brown and dry.
Reduce watering to allow sugars to concentrate. Check daily for ripeness. Do not overwater at this stage. Be ready to harvest when ripe.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Row covers until flowering; neem oil or insecticidal soap; remove by hand; plant trap crops like nasturtiums
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Wrap base of vine with aluminum foil; inject BT into stems; plant succession crops; remove infested vines immediately
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Strong water spray; insecticidal soap; neem oil; encourage natural predators; reflective mulches
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Increase humidity and watering; miticide or neem oil; remove heavily infested leaves; encourage predatory mites
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Yellow sticky traps; insecticidal soap; neem oil; improve air circulation; remove infested leaves
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Improve air circulation; avoid wetting foliage; sulfur dust or fungicide spray; remove affected leaves; plant resistant varieties
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Use disease-resistant seeds; improve drainage; rotate crops; remove infected plants; solarize soil if severe
Uses
Fresh eating and juice
CulinaryCrimson Sweet watermelon is prized for its sweet, crisp red flesh perfect for eating fresh, slicing into salads, or juicing. The high sugar content (around 11-12 Brix) makes it one of the sweetest melon varieties available. [source]
Summer beverages and desserts
HouseholdUse fresh flesh for smoothies, granitas, cocktails, and frozen treats. The high water and sugar content makes it ideal for refreshing summer beverages. [source]
Seed saving and consumption
CulinaryCrimson Sweet seeds can be saved for future seasons or roasted and eaten as a nutritious snack high in magnesium and manganese. [source]
Hydration and nutrient source
MedicinalWatermelon is 92% water and rich in lycopene, vitamins A and C, and citrulline, which may support cardiovascular health and recovery. [source]
Pollinator support
WildlifeThe vibrant yellow flowers attract bees, butterflies, and other essential pollinators to the garden, supporting biodiversity. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest when melon shows a pale yellow spot where it rested on ground (no green remaining in this spot), skin loses bloom/waxy coating, and melon sounds hollow when thumped. The tendril closest to the fruit stem should be brown and dry. Ripe melons do not slip easily from the vine—cut with a sharp knife leaving 1-2 inches of stem attached. Best flavor develops after harvest as sugars continue concentrating for 2-3 days at room temperature.
Fun Facts
- 🌱 Crimson Sweet was developed by Elwyn Meade at the University of Florida in the 1960s and quickly became the standard commercial watermelon variety, dominating farmers markets for decades.
- 🌱 Watermelons are approximately 92% water, making them one of the most hydrating fruits—it takes about 90 gallons of water to produce a single watermelon.
- 🌱 The red flesh color of Crimson Sweet comes from lycopene, the same antioxidant found in tomatoes, which develops as the melon ripens and is not present in unripe melons.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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