Watermelon, Moon And Stars
How to Sow and Plant
Sowing Seed Indoors:
- Direct sowing is recommended, but to get a head start you can start watermelon indoors 3-4 weeks before the last frost in individual biodegradable pots indoors. Sow 2-3 seeds per pot.
- Sow seeds 1 inch deep in seed-starting formula
- Keep the soil moist at 70 degrees F
- Seedlings emerge in 7-10 days
- As soon as seedlings emerge, provide plenty of light on a sunny windowsill or grow seedlings 3-4 inches beneath fluorescent plant lights turned on 16 hours per day, off for 8 hours at night. Raise the lights as the plants grow taller. Incandescent bulbs will not work for this process because they will get too hot. Most plants require a dark period to grow, do not leave lights on for 24 hours.
- Seedlings do not need much fertilizer, feed when they are 3-4 weeks old using a starter solution (half strength of a complete indoor houseplant food) according to manufacturer’s directions.
- Thin to one plant per pot. PLEASE NOTE: Seedless varieties do not produce pollen and therefore cannot pollinate themselves. A pollinator (seeded variety) is included to insure a good fruit harvest. Both seedless and the pollinator seed must be planted together. The pollinator seed is the larger seed.
- Before planting in the garden, seedling plants need to be “hardened off”. Accustom young plants to outdoor conditions by moving them to a sheltered place outside for a week. Be sure to protect them from wind and hot sun at first. If frost threatens at night, cover or bring containers indoors, then take them out again in the morning. This hardening off process toughens the plant’s cell structure and reduces transplant shock and scalding.
Sowing Directly in the Garden
- Sow in fertile, warm soil after danger of frost has passed.
- Sow seeds 3 inches apart in groups of 4-6 in raised hills. Cover with 1 inch of fine soil and firm lightly.
- Space groups 5-7 feet apart each way.
- Keep evenly moist.
- Seedlings emerge in 7-10 days.
- Thin to 2 or 3 strongest seedlings in each group when they are 1-2 inches high.
- PLEASE NOTE: Seedless varieties do not produce pollen and therefore cannot pollinate themselves. A pollinator (seeded variety) is included to insure a good fruit harvest. Both seedless and the pollinator seed must be planted together. The pollinator seed is the larger seed.
How to grow moon and stars watermelon (Citrullus lanatus)
Watermelons are tender annuals that require warm temperatures to germinate and fruit. Sow seeds directly into garden soil when all danger of frost is past. Plant ½” deep, 3 seeds per hill. Space hills 12-18” apart with 6’ row centers. Thin to one strong seedling in every hill. Plants may be started indoors for transplanting. Sandy, well-drained soils are best.
95-100 days. Fruit is ripe when the nearest tendril is brown and dry; when the spot that touches the ground turns from white to yellow; when the blossom end is soft; and the fruit sounds hollow when tapped. Cut the fruit from the vine with a sharp knife or pruners.
Moon and Stars watermelon sports dark green skin speckled with yellow spots of varying sizes. The vine is compact, making it ideal for small gardens. The flesh of the fruit is commonly red, yellow, or orange. The rind is thick and good for pickling, and the flesh has a sweet flavor. The fruit can grow up to 40 pounds under ideal conditions, though 10-15 pounds is more commonplace.
Moon and Stars watermelon is one of the most popular heirloom varieties in the United States. Commercial rights were sold to Peter Henderson & Company of New York in the 1920s. The creator of the plant is unknown, but it was originally called “Sun, Moon, and Stars.” By the 1970s it had almost completely disappeared from American Gardens, until it was “rediscovered” and included in the 1981 Fall Harvest Edition of Seed Saver’s Exchange.
Connection to Extension
Moon and stars watermelon is one of the seeds offered by Strawbery Banke Museum through our free seed for education program.
This planting guide was created through partnership among Strawbery Banke Museum, New Hampshire School & Youth Garden Network, New Hampshire Master Gardener Alumni Association and UNH Extension Master Gardeners.
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Moon and Stars Watermelon
Watermelons (Citrullus lanatus) are warm season tender annuals in the Cucurbitaceae family, which includes cucumbers, summer squash and winter squash, and gourds
Soil Nutrients and Requirements
Sandy or light textured soils that warm easily in the spring are desirable. Melons are heavy feeders. Give 80-120 lbs of N per acre. Calcium deficiency can lead to blossom end rot, especially when adequate moisture is not available. Use dolomitic limestone.
Plant spacing: 12-18″
6’ row centers.
When to Sow
Days to maturity are from transplanting, add 10-14 days if direct seeding.
Plastic mulch and floating row cover are used to increase soil and air temperatures as well as ward off insects, especially cucumber beetles.
Ripeness is determined by four methods: when the tendril nearest the fruit is dried and brown; when the ground spot has turned from white to yellow; when the blossom end of fruit becomes soft; and the ubiquitous “thump test”— fruit should sound hollow. Cut fruit cleanly from the vine to avoid stem-end rot.
Store at 45°F and 85% humidity for up to 3 weeks.
- Striped cucumber beetles cause feeding damage to the leaves, and often transmit bacterial wilt. Larvae feed on the plant roots. Row covers can provide effective protection, but must be removed during flowering to allow pollination. Practice crop rotation and good sanitation to eliminate overwintering habitat. Frequent application of kaolin clay and/or pyrethrum have shown some effective control.
- Squash vine borer will cause plants to look wilted even when moisture is plentiful. Slice open stem and remove and destroy.
- Squash bugs can be controlled by handpicking. Bury or compost plant residues at the end of the season.
- A relatively new disease called Bacterial Fruit Blotch (BFB) (Acidovorax avenae subsp. citrulli) particularly affects watermelons. BFB can be spread by seed and by infected transplants, as well as from plant residues and/or alternative hosts. Symptoms on seedlings are “oily” dark lesions that typically parallel the veins. Seedlings of some varieties die rapidly, while others persist into maturity and set fruit that will then become contaminated by the inoculum on the leaves. Fruit symptoms are characterized by a dark green stain on the upper side of the fruit. Infection does not penetrate the rind, but eventually causes it to crack and often emit white foam, caused by gases formed by invading pathogens. There are no resistant varieties as of yet. Other cucurbit crops can also be infected by BFB, but the disease does not typically affect the fruit in these crops. However, other infected crops can serve as a source of inoculum for watermelon crops. Due to the prevalence and severity of BFB, customers wishing to purchase over ¼ ounce of watermelon seed must print, sign and submit the Watermelon Waiver. We cannot ship any amount of watermelon seed to South Carolina.