How to Grow Watermelons: Sow watermelon seed in the garden or set out transplants 3 to 4 weeks after the last average frost date in spring. Start watermelon seed indoors about 6 weeks before transplanting
The watermelon is a tender, warm-weather annual. Watermelons along with muskmelons and cantaloupes are sometimes called summer melons.
• Sow watermelon seed in the garden or set out transplants 3 to 4 weeks after the last average frost date in spring.
• Start watermelon seed indoors about 6 weeks before transplanting seedlings into the garden. Start seed indoors in 4-inch or larger biodegradable peat or paper pots that can be set wholly into the garden so as not to disturb the roots.
• Watermelons require 65 to 90 frost-free days to reach harvest.
About Watermelons. The watermelon is a long-trailing annual plant. Watermelons can be solid green or striped green and white. Watermelons can be oval, oblong, and round. Fruits can weigh from 10 or 15 pounds to more than 100 pounds and are commonly 30 pounds or more. The watermelon has a thick, solid rind with sweet, succulent flesh that can be pink, red, yellow, orange, or grayish white. Male and female flowers appear on the same vine.
Watermelon Yield. Grow 2 watermelon plants for each household member.
Site. Plant watermelons in full sun. Watermelons grow best in loose, well-drained, but moisture-retentive soil rich in organic matter. Add aged compost to the planting bed before planting. Melons prefer a soil pH of 6.0 to 6.8.
Watermelon Planting Time. Sow watermelon seed in the garden or set out transplants 2 to 3 weeks after the last average frost date in spring. Start watermelon seed indoors about 6 weeks before transplanting seedlings into the garden; start seed in biodegradable peat or paper pots at least 4 inches in diameter that can be set wholly into the garden so as not to disturb roots. (This is recommended in short growing season regions where the soil warms slowly in spring.) Melon seed will germinate in 10 days at 65°F. Watermelons grow best in air temperatures ranging from 70° to 90°F. Avoid growing watermelon where night temperatures dip below 50°F; this will cause fruit to lose flavor. If temperatures exceed 90°F for several days, flowers will drop without setting fruit. Watermelons require 65 to 90 frost-free days to reach harvest and will tolerate no frost. In cool or short-season regions, grow smaller varieties that come to harvest quickly.
Planting and Spacing Watermelon. Sow watermelon seed 1 inch deep. Sow 4 to 6 melon seeds in mounds or inverted hills 24 inches across; thin to the 2 or 3 strongest seedlings in each hill when seedlings have developed three or four true leaves (or set 2 or 3 transplants in each hill). Cut the thinned seedlings at soil level with scissors. Space mounds or inverted hills 6 feet apart. Mounds can range in height from a few inches to more than 12 inches tall; mounds will allow vines to run away down the slope. Use inverted hills where the weather and soil are very dry and plants will benefit from the collection of rain or irrigation water. Make an inverted hill by removing an inch or two of soil to from a circle 24 inches across; use this soil to make a rim around the circle. The rim also will protect young plants from heavy rains that might wash away the soil leaving shallow roots exposed. More tips: Watermelon Seed Starting Tips.
Water and Feeding Watermelon. Watermelons are 95 percent water. They require plentiful regular, even watering for quick growing. Keep the soil moist until fruit reaches full size then stop watering while the fruit ripens. Mulch to retain soil moisture. Avoid watering plants overhead which can result in mildew. Prepare planting beds with aged compost; add aged manure to beds the autumn before planting. Side dress melons with compost or manure tea every 2 to 3 weeks during the growing season.
Companion plants. Corn, radish, beans, nasturtium.
Watermelon Care. Encourage watermelon plants to set three or four fruits at the same time; if a plant sets one fruit early, pinch it out to encourage the plants to develop several fruits at the same time. One fruit off to a head start can suppress all further fruiting on the vine until the fruit matures. Pinch back multiple flowers to permit just a few fruits to form on each vine. If flowers die without setting fruit, they are probably male flowers, which do not produce fruit; each plant produced both male and female flowers.
Cultivate carefully around vines until they cover the ground and smother out competing weeds. Support melons on a low tripod or A-frame trellis to keep them off wet ground; use netting or a bag to support trellis-grown melons. For sprawling watermelons, place a board under each melon to keep the fruit clean and dry. Regular, even watering will help fruits avoid blossom-end rot which is caused by fluctuation of soil moisture. More tips: How to Grow Watermelon for Best Flavor.
Container Growing Watermelon. Watermelons are usually too large to grow in a container. Select a bush, dwarf- or mini-cultivar to grow in a container. Place a trellis or other support next to the plant to save space and increase yields. Choose a container at least 18 inches deep that can support a vining plant. In short growing season regions extend the season by starting melons indoors and moving them out when the weather has warmed.
Watermelon Pests. Aphids and cucumber beetles will attack melons. Hose away aphids with a blast of water or pinch out infested foliage. Hand pick and destroy cucumber beetles promptly; they can transmit cucumber bacterial wilt to melons.
More tips: Melon Growing Problems: Troubleshooting.
Watermelon Diseases. Watermelons are susceptible to anthracnose and bacterial wilt. Planting disease resistant varieties when they are available and maintaining the general cleanliness and health of your garden will help cut down the incidence of disease. Do not handle the vines when they are wet. If a plant does become infected remove it before it can spread disease to healthy plants.
Bacterial wilt which is spread by cucumber beetles can cause watermelon plants to suddenly wilt and die just as they begin to produce fruit. Control cucumber beetles as soon as they appear.
Anthracnose is a soil-borne fungal disease that can cause leaf spots, leaf drop, wilting and sometimes death. Keep the garden clean and plant disease resistant varieties. Remove diseased plants from the garden immediately.
Harvest Watermelon. Watermelons will be ready for harvest 65 to 90 days after sowing. When watermelons are ready for harvest the vine’s tendrils will begin to turn brown and die off. A ripe watermelon will make a dull sound when thumped. The soil side of a watermelon will turn from white to pale yellow when the fruit is ready for harvest. Ripe melons will have a sweet aroma at the stem end. Limit water for a week in advance of harvest to concentrate sweetness.
Storing and preserving. Watermelons will keep in the refrigerator for up to one week, but sweetness and flavor may diminish. It takes about 12 hours to chill a large watermelon. Watermelons can be kept in a cool, moderately moist place for 2 to 3 weeks without refrigeration. Melon flesh can be frozen and rinds can be pickled.
More tips: How to Harvest and Store Watermelon.
Watermelon Varieties.
• Icebox size watermelons: Early Midget (65 days); Garden Baby (70 days); Golden Midget (65 days); Sugar Baby (68-96 days); Tiger Baby (80 days).
• Oblong, green rind: Northern Sweet (68 days).
• Oblong, grayish rind: Allsweet (100 days); Calsweet (92 days); Charleston Gray (90 days); Desert Storm (80 days); Fiesta (85 days); Regency (82 days); Royal Majesty (80 days); Sangria (85 days); Strawberry (85 days); Sun Sweet (85 days); Sweet Favorite (64-79 days).
• Round, green: Black Diamond (75-95 days); Black Diamond Yellow Belly (90 days); King and Queen (80-90 days); Moon and Stars (100 days).
• Round, striped: Crimson Sweet (80-96 days); Navajo Sweet (90 days); Super Sweet (90 days).
• Giant sized: Carolina Cross (100 days).
• Space savers: Bush Sugar Baby (80 days); Garden Baby (75 days); Petite Sweet (75 days); New Hampshire Midget (77 days); Sugar Baby (79 days).
• Yellow or orange flesh: Arikara (85 days); Yellow Doll (75 days).
More varieties to grow: Watermelons for Home Gardens: Top 12 Varieties.
Common name. Watermelon
Botanical name. Citrullus vulgaris
Origin. Tropical Africa
More tips:
We are interesting in buying Black Diamond Watermelon’s Wholesales next season for resale.
Please give some tips for growing watermelon. I live in the tropical country of Fiji.
Growing Watermelon: Watermelon originated in tropical Africa. Small, round watermelons can be successfully grown in cooler short-season regions, large oblong watermelons up to 50 pounds can be grown in tropical regions. Watermelons do best where the seaon is warm and long. Direct seed 5-6 seeds in mounded hills spaced 6-8 feet apart; direct sow 4 weeks after the last frost. When the plants emerge thin to the best 2 plants in each hill. (For those growing in frost areas, sow seeds indoors 3-4 weeks before the last spring frost in 3-inch pots for transplanting out when temperatures warm to 75F.) Watermelon prefers rich, light, well-drained soil–so dig in plenty of compost before sowing or transplanting. Side-dress watermelons with dried manure or organic fertilizer when they are still upright, before they sprawl. Make sure the plants get 1 inch of water every week, but don’t overwater. If you are in a rainy region, be sure the plants are set on high well-drained hills. Be consistent in watering. Reduce water 4 weeks before harvest when melons are about two-thirds mature size. Watermelons grow best where the day temperatures are between 70F and 90F and where night temps do not fall below 60F.
Thanks for your useful comments on growing Watermelons. I was told by someone not to transplant watermelons and grow them directly in the final location.
I am in Dubai and summer temperatures are regularly 40 to 50 degrees Centigrade. I planted 10 seeds in February and I have around 5 plants. Now in Mid June – I have one fruit that was the first one (appeared in early May) and it just stopped growing. Its not growing in size though it looks green and healthy. I have another fruit that is growing very well and is like a smallish football now (Appeared at end of May).
Q1: When is the best time to pick the fruit? How do I know that it is ripe?
Q2: There are still female flowers coming on some of the plants. I am pollinating these using the male flowers. But will these grow into good fruits – now that we are in June (Full summer).
This is my first garden – just had it laid end of Dec 2010 and I am experimenting with several different plants. I did well with Tomatoes in Feb and March and I had Aubergines at the same time.
Q3: What other fruits/ veg will be suitable for Dubai weather (particularly in the HOT Summer months)?
Dear Mr Moosa
Hi,
I am producing several crops in large scale in a country by the same weather condition. You can easily plant Watermelon, Abusabaein, Maize,Sweet corn, Sesame,Muskmelon, Different other crops
Just you should adjust the best time of planting for different crops.
Is it possible to grow Watermelons outdoors in the north of England? We get plenty of rain, but not so much sun!
I have been growing watermelons in my greenhouse, this is my first time growing them. One of the vines seems to be dying; it’s leaves go yellow in spots, then brown and wilt and the stem is doing the same. Does anyone know what could cause this? The other two plants nearby are showing the same symptoms but not as badly-any chance I can save them? I prefer organic gardening if possible, but would welcome any recommendations. As these are the only three plants I have I really don’t want to destroy them all. Many thanks.
Merry
Watermelons and other melons grow best in full sun in rich, loose, warm soil, soil no cooler than 60F. Keep the soil warm by covering it with black plastic. Depending upon the cultivar, your watermelons will need 85 to 110 days of warm weather to reach harvest. Plant your watermelons in the warmest part of your garden, perhaps near a wall, fence, or building where it will receive reflected heat. Try growing a small, quick-to-harvest variety: Cole’s Early, Garden Baby, Sugar Baby, Sunshine, Yellow Baby, or Yellow Doll. Given the rainy situation, you might try growing your watermelons under plastic tunnels; you will protect them from the rain and trap solar heat at the same time.
Melon leaves that turn brown and wilt may have angular leaf spot, anthracnose, or Alternaria blight. Angular leaf spot, a bacterial disease, starts with water-soaked spots on leaves and stems; a bacterial ooze will follow on leaf undersides. Prune off infected leaves and stems; spray with copper to slow the spread of disease. Anthracnose, a fungal disease, can start as yellow water-soaked spots on melons; leaves turn brown. Spraying with sulfur can help slow the spread of this disease. Alternaria blight, a fungal disease, causes concentric rings on melon leaves, leaves yellow an die. Remove leaves from infected plants; spray plants with a baking soda solution or compost tea. These diseases can be slowed by irrigating at the base of plant stems, not overhead. Allow plant foliage to dry each day. If your plants die, you will want to thoroughly clean the greenhouse or planting bed; remove all crop debris to be rid of any remnants of the problem. Plant so that there is plenty of air circulation around plants. Choose disease resistant seed or starts for planting.
Vegetable gardening in hot summer regions calls for a shift of your growing season. Grow your warm-season crops so that they come to maturity before average daytime temperatures exceed 90F. This will mean planting and growing your crops earlier and later to avoid the hottest time of the year–when vegetables can not grow. You may want to choose cultivars that are quick maturing (see the Quick-growing list in the Topics Index) to get your crops in between very cool and very warm seasons. Also check the Hot Weather Garden topics index for articles on using shade, water, and mulch to grow vegetables in very hot weather. Hot region vegetable gardens can be grown in sunken beds–beds dug below the soil level; these beds will be cooler, closer to ground water and more easily shaded with shade cloth set over a frame. When temperatures are above 90F, expect crops to stop growing–they will wait until temperatures decline to resume growing, provided they don’t become too stressed and die.
Water melons growing on pavement https://www.youtube.com/watch?v=eOER24yKWo4
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i have grown water melon but what fertilizers to be applied coz they are two weeks now and how can i get high yields. thanks
Watermelons and other melons do best in loose, rich soil. Add plenty of aged compost to the planting beds–before you plant and as a side dressing once plants are growing. You can never add too much aged compost to a planting bed. If you want to use a store-bought fertilizer, choose an organic or natural fertilizer that is low in nitrogen and high in phosphorus and potassium. Follow the directions on the label. Choose the strongest vines and allow two or three watermelons per vine to mature. Be sure to keep the soil consistently moist for uninterrupted growth.
what about fertigation? Please give details about fertigation of water melon.
Watermelon–like other fruiting vegetables–is best fertilized with a low nitrogen–higher phosphorus and potassium fertilizer. for example 5-10-10. Fertigation systems inject fertilizer into the irrigation lines–these systems use liquid fertiizers or water soluble powder fertilizers (made into a liquid before placing into the fertigation system). Fertigation systems commonly come with instruction sheets to help you set the flow of fertilizer into the system. Instruction sheets from each manufacturer should give you suggested mix and flow for each crop.
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First-timer question: How can I protect my growing watermelons from critters? I have lots of squirrels and birds, plus the occasional possum, raccoon, and fox (and the neighbor’s stupid cat). How much light and air does the actual melon need? I’m growing Crimson Sweet in SW Missouri.
Your watermelons will benefit from plenty of sunshine and good air circulation. Plant in full sun and, if possible, where there is a gentle breeze. Bird netting will keep birds from visiting the garden–and that may keep the neighbor’s cat at home. You can also spray your vines with a garlic-based spray repellent. You can get an animal repellent at the garden shop or make your own: use several cloves of garlic in a quart of water, whirled in a blender, strain to remove solids, add a drop of liquid dish soap as a spreader-sticker, and spray the plants.
First time grower: My watermelon are planted in my pool area since water is always plentiful through the season and they are doing well. My question though: I have three vines that have made it to the concrete around my pool and are heading for the water. They have three fruits growing. Will the watermelon sustain on concrete that is daily too hot for my feet? 125F+ They look to be doing fine.
You can direct the watermelon vines away from the concrete and back into the planting beds. The vines themselves are simply growing–not actually heading for the pool. Keep the soil moist around the stem and roots of the plant while fruit is developing. Yes, the concrete may get so hot that the moisture in the melon–watermelons are 90 percent water–can heat up and crack the fruit. So best to let the melons develop in the garden–on top of a patch of straw.