Yellow Watermelon Plant Profile

Yellow Watermelon Plant

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In the quest to breed watermelons with the least seeds and fastest maturing time, flavor sometimes gets pushed to the side. Not so with yellow watermelon plants. Although the yellow watermelon often has seeds, there is no compromise on flavor. In fact, many watermelon connoisseurs argue that the yellow watermelon yields fruits that are superior in taste to the standard red cultivars. From the exterior, the fruits look no different from the red types: they are light green with dark green stripes, and plants have the same lobed leaves. Some yellow watermelon plants produce large fruits, between 20-40 pounds, ideal for sharing at a picnic or party, while others produce small, six pound fruits. The plants are vigorous, and grow best in areas with long, hot summers. Grow a mix of yellow and red watermelon vines in the same garden, and dazzle your friends with a yellow and red medley of fruit at your next Labor Day celebration.

Botanical Name Citrullus lanatus
Common Name Yellow watermelon
Plant Type Tender annual
Mature Size 10-foot vines
Sun Exposure Full sun
Soil Type Moist, rich, and loamy
Soil pH Acific; 6.0 to 6.8
Bloom Time May to September
Flower Color Yellow
Hardiness Zones Grow as an annual in all zones
Native Area Africa
Young Yellow Watermelon
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Yellow Watermelon Slice
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Ripe Yellow Watermelons
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How to Grow Yellow Watermelon

Yellow watermelon plants like lots of sun and soil with good drainage and high fertility. If you live in an area with short summers, choose a bush baby variety that matures in under 70 days. Plants are somewhat drought tolerant as they mature. Prevent common pests and diseases by not growing yellow watermelons where other melons, squash, or cucumbers were grown the previous year.

Light

Yellow watermelon plants need a full day of sun. Plant them away from buildings or tall plants that cast shade.

Soil

A rich, sandy loam will produce the healthiest yellow watermelon harvest. Add compost or manure to poor soils, and use raised beds in areas with clay to improve drainage.

Water

Keep soil moist, but not soggy until fruits form. After fruits reach softball size, water only when the surface of the soil is dry. Overwatering can cause rapid growth that leads to cracking.

Temperature and Humidity

Yellow watermelons love hot weather, but if an extended hot spell in the triple digits is stressing plants, you can use shade cloth. Hot weather and high humidity can make plants susceptible to powdery mildew. Increase spacing to help air circulation and reduce fungal spores.

Fertilizer

Chemical fertilizers aren't necessary to grow yellow watermelons. The slow, steady stream of nutrients from leaf mold, compost, or manure as a top dressing will increase soil fertility and tilth.

Varieties of Yellow Watermelon

'Yellow Doll' hybrids are common in the trade, and produce small six pound melons with small seeds in 68 days. 'Yellow Baby' hybrid has a thin rind and few seeds in its nine pound fruits. 'Lemon Krush' hybrid is a long season, large type resistant to common fungal disease. 'Mountain Sweet Yellow' is an heirloom that produces jumbo fruits in 100 days.

Yellow Doll Watermelon
Yellow Doll Watermelon. CostinT/Getty Images
Yellow Baby Watermelon
Yellow Baby Watermelon. Akepong Srichaichana / Getty Images
Lemon Krush Watermelon
Lemon Krush Watermelon. Yurich84/Getty Images

Harvesting Yellow Watermelon

You can determine the ripeness of a yellow watermelon by observing small changes in the fruit and the vine. The vine or leaves closest to the fruit may become yellow or brown as growth slows or stops. The rind may change from shiny to dull and rough, and the bottom of the fruit will turn pale or yellowish.

Growing From Seeds

Starting yellow watermelon seeds indoors is not recommended. Wait until soil temperatures are at least 70 degrees F before starting outdoors. It's important that the soil be warm, not just the air temperatures; about two weeks after the last frost of the season. You can also plant in raised beds or cover the soil with plastic to speed up warming.

Make a mound of soil six to eight inches high for seed planting. Rows should be at least four feet apart; mounds should be three feet apart. Plant two or three seeds in the mound, six inches apart. After germination occurs in about eight days, remove all but the most vigorous seedling.

Common Pests/Diseases

Check daily for squash bugs and squash vine borers on young plants, and remove egg masses or treat with carbaryl. Fungal diseases are more common in cold or wet weather. Reduce fungal spores by watering plants at soil level.

Yellow Watermelon vs Red Watermelon

The seeds, plants, and fruits of red and yellow watermelon look the same, so it's important to purchase properly labeled seeds or plants to ensure that you don't get a red surprise when you slice open your melon. You can save seeds from an organic heirloom like 'Mountain Sweet Yellow' and get plants that grow true to type, but you will not get identical offspring by saving seeds from a hybrid like 'Yellow Doll.'

Yellow and Red Watermelons
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