Crimson Sweet Watermelon Seeds – Heirloom Non-GMO AAS Winner

Crimson Sweet Watermelon Seeds

Grow one of the classic American picnic watermelons with Crimson Sweet, Citrullus lanatus 'Crimson Sweet'. This heirloom, Non-GMO, open-pollinated variety produces large striped melons with crisp, juicy red flesh and is an All-America Selections award-winning variety.

Crimson Sweet is made for warm summer gardens. Its vigorous vines appreciate full sun, warm soil, generous growing space, and consistent moisture while the fruits develop.

Product Highlights

• Classic seeded picnic watermelon.
• Heirloom, Non-GMO, open-pollinated variety.
• All-America Selections award-winning watermelon.
• Large green-striped fruit with crisp, sweet red flesh.
• Approximately 80–90 days to maturity.
• Heat-tolerant warm-season annual with vigorous vines.

Plant Profile

• Common Name: Watermelon
• Botanical Name: Citrullus lanatus
• Variety: Crimson Sweet
• Type: Seeded Picnic Watermelon
• Cultivar Type: Heirloom, Open-Pollinated
• Life Cycle: Annual
• Growth Habit: Vining
• Light: Full sun
• Fruit: Green striped rind with red flesh
• Typical Fruit Size: Large picnic-size melons, commonly around 20–25 lb under favorable conditions
• Soil: Loose, fertile, well-drained sandy or loamy soil
• Preferred Soil pH: Approximately 6.0–6.5
• Days to Maturity: Approximately 80–90 days

Growing Overview

Watermelon is highly sensitive to frost and cold soil. Direct sow Crimson Sweet after the danger of frost has passed and the soil is thoroughly warm. Gardeners with shorter summers can start seeds indoors about 3 weeks before transplanting.

Sow approximately 1/2–1 inch deep. Warm soil around 70–85°F provides favorable germination conditions, and seedlings commonly emerge in about 4–12 days under suitable conditions.

Allow approximately 36–48 inches between plants and generous row spacing for the vigorous vines. Full sun is essential for strong growth and fruit development.

Watering & Fruit Development

Keep the soil consistently moist during vine growth, flowering, and early fruit development. Deep watering encourages a stronger root system and is preferable to frequent shallow watering.

As fruits approach maturity, avoid excessive irrigation. Too much water late in development can reduce fruit quality or contribute to cracking.

Disease Resistance

Crimson Sweet has long been recognized for useful resistance to anthracnose and Fusarium wilt. Resistance does not mean immunity, and effectiveness can differ among pathogen races and growing regions, so good crop rotation, drainage, airflow, and garden sanitation remain important.

Harvest & Enjoy

Crimson Sweet generally reaches maturity in approximately 80–90 days. Because watermelon does not become sweeter after harvest, identifying full ripeness on the vine is important.

Look for several signs together: the tendril closest to the fruit begins to dry, the ground spot changes toward yellow, and the rind becomes less glossy. Ripe Crimson Sweet has crisp red flesh suited to fresh slicing, picnics, fruit salads, and summer meals.

What to Expect

Fruit size can vary considerably with temperature, fertility, water, spacing, pollination, and the number of melons carried by each vine. Around 20–25 pounds is common for Crimson Sweet under favorable conditions, but this should not be treated as a guaranteed fruit weight.

Crimson Sweet is a seeded diploid watermelon. Its flowers require pollination for fruit development, and the variety can also provide pollen when grown near compatible seedless watermelon plants.

Frequently Asked Questions

Is Crimson Sweet a seeded or seedless watermelon?

Crimson Sweet is a traditional seeded watermelon. The mature red flesh contains seeds and the variety is open-pollinated rather than a triploid seedless hybrid.

How long does Crimson Sweet take to mature?

Expect approximately 80–90 days under suitable warm growing conditions. Temperature, planting method, soil fertility, and other environmental factors can shift harvest timing.

How much sun does watermelon need?

Grow Crimson Sweet in full sun. A sunny location supports vigorous vines, fruit development, and sugar accumulation.

How do I know when the watermelon is ripe?

Check for a drying tendril near the fruit, a yellow ground spot, and a rind that becomes less glossy. Using several ripeness indicators together is more reliable than relying on only one.

Does Crimson Sweet have disease resistance?

The variety has documented resistance to anthracnose and Fusarium wilt, but resistance varies with pathogen race and local disease pressure. It should not be treated as complete immunity.