How to grow watermelons: When to plant and how to feed your watermelon plants


The cantaloupe or muskmelon is a tender, warm-weather plant. Cantaloupes grow best in very warm to hot weather.

  • Sow cantaloupe (muskmelon) seed in the garden or set out transplants 3 to 4 weeks after the last average frost date in spring.
  • Start cantaloupe seed indoors about 6 weeks before transplanting seedlings into the garden. Start seed indoors in biodegradable peat or paper pots that can be set directly into the garden.
  • Cantaloupes require 70 to 100 frost-free days to reach harvest; cantaloupes will tolerate no frost.

The tan, netted melon commonly referred to as cantaloupe is actually a muskmelon. A true cantaloupe has a rough warty rind.

Muskmelons along with watermelons are termed summer melons because they come to harvest from mid to late summer.

Winter melons—which are grown during the summer like muskmelons–are ready for harvest in late summer and autumn. Winter melons include casaba, Crenshaw, honeydews, and Persian melons.

Cantaloupes, muskmelons, honeydew melons, and other summer melons, as well as winter melons, have the same growing requirements.

Where to Plant Melons

  • Plant melons in full sun.
  • Melons grow best in loose, well-drained, loamy soil rich in organic matter.
  • Add several inches of aged compost and aged manure or commercial organic planting mix to the planting bed before planting. Turn the soil to 12 inches deep.
  • Melons prefer a soil pH of 6.0 to 6.8.
  • Melons can be grown on mounds, raised beds, up trellises, or in flat planting beds. Pre-warm the soil by placing black plastic or permeable black garden fabric across the planting area two weeks before planting. When planting cut x-shaped slits in the covering.

Melon Planting Time

  • Sow melon seeds in the garden or set out transplants 3 to 4 weeks after the last average frost date in spring.
  • Start melon seeds indoors about 6 weeks before transplanting seedlings into the garden.
  • Start seeds 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.
  • Starting melons indoors is recommended in short growing season regions where the soil warms slowly in spring.
  • Melon seeds will germinate in about 10 days at 65°F.
  • Melons grow best in air temperatures ranging from 70° to 90°F.
  • If temperatures exceed 90°F for several days, flowers will drop without setting fruit.
  • Melons require 70 to 100 frost-free days to reach harvest and will tolerate no frost.
  • In cool or short-season regions, grow smaller varieties that come to harvest quickest.

Planting and Spacing Melons

  • Sow melon seed 1 inch deep.
  • Space seeds 18 inches apart in the garden.
  • Plant melons on raised mounds or hills that are 24 inches across or wider. Mounds warm quickly in spring and stay warm through the growing season.
  • Sow 4 to 6 melons seeds on each mound; when seedlings have developed three or four true leaves, thin to the 2 or 3 strongest seedlings on each hill.
  • Cut the thinned seedlings at soil level with scissors so as not to disturb the roots of the remaining plants.
  • Space mounds 4 to 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.
  • Move an inch or two of soil across the top of the mound to form a rim around the top of the mound. The rim will protect young plants from heavy rains that might wash away the soil leaving shallow roots exposed; the rim will also hold irrigation water during hot weather.

Growing Melons on Vertical Support

  • Muskmelons and other summer melons can be grown up trellises or fences.
  • You can also train melon vines up an A-frame. Lean two trellises into each other and tie them together at the top.
  • A trellis set against a solid fence or the wall of a building will benefit from reflected heat.
  • Make sure the vertical support is well anchored. Heavy fruits can tip a trellis late in the season.
  • Space melons at the base of a vertical support 12 inches apart.
  • Train vines up supports with elastic horticultural tape.
  • Melon plants can grow up to 8 feet tall and wide or more.
  • Most melon vines will support the weight of a melon, but you can use garden netting tied to the support to support melons.
  • Melons grown on vertical supports will get full sun exposure and good air circulation which can help prevent fungal diseases.

Growing Melons in Containers

  • Melons are usually too large to grow in containers.
  • Select a bush, dwarf- or mini-cultivar to grow in a container.
  • Choose a container at least 18 inches wide and deep that can support a vining plant.
  • Place a trellis or other support next to the plant to save space and increase yields.
  • In short growing season regions, extend the season by starting melons in containers indoors then move them outdoors when the weather warms.

Melon Companion Plants

  • Plant melons with corn, radishes, beans, and nasturtiums.
  • Plant herbs such as dill or bee balm near melons to attract pollinators.

Watering Melons

  • Melons require plentiful regular, even watering for quick growing.
  • Give melons 1 inch of water (16 gallons) or more each week.
  • Water with drip irrigation or a soaker hose to avoid wetting leaves. Wet leaves are susceptible to fungal diseases.
  • Keep the soil around melons evenly moist from planting until the fruit begins to develop.
  • You can cut back on watering once fruit begins to develop but don’t let the soil go dry. Less water will enhance sweetness.
  • Dry soil a week before harvest will produce the sweetest melons.
  • Avoid watering plants overhead which can result in mildew.

Feeding Melons

  • 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.
  • You can also feed melons a diluted solution of fish emulsion every 2 weeks.
  • Flat, tasteless melons may suffer from a lack of magnesium or boron in the soil. Fruits can be sweetened by giving them a dose of Epsom salts and borax. For home garden use, use about 6½ tablespoons of Epsom salts and 3½ tablespoons of household borax added to five gallons of water. Spray-mist the vines with this solution.

Caring for Melons

  • Cultivate carefully around vines until they cover the ground and smother out competing weeds.
  • Mulch around melon plants with straw or dry, chopped leaves to retain soil moisture, slow weed growth, and keep fruits off of the soil.
  • Support melons on a low tripod or A-frame trellis to keep them off wet ground; use netting or a bag to support trellis- or fence-grown melons.
  • Pinch back flowers to permit just 4 fruits to form on each vine. Fewer melons on a plant will be larger, sweeter, and come to harvest quicker.
  • You can also pinch away some flowers so that a newly pollinated flower begins growing a new fruit every two weeks. This can stagger the harvest of fruit from one plant.
  • For melons sprawling across the ground, place a shingle, tile, half milk jug, or clay pot under each melon to keep it dry and prevent rot. These items will also soak up solar heat and keep the fruit warm at night.
  • Avoid pruning leaves off of plants until just before harvest. Leaves help produce the sugars melons need for sweetness. Pull back leaves that cover fruits to give fruits maximum sun exposure.
  • Remove all new blossoms that appear within 50 days of the first frost in autumn. This will allow the plant to ripen fruit already on the vine before the first frost.

Melon Pollination

  • Melons produce male and female flowers on the same plant.
  • Male flowers appear a week before female flowers. Female flowers have a small bulge (an unfertilized fruit) near the stem end of the blossom.
  • Bees or other pollinators must carry pollen from male to female flowers for pollination, flowering, and fruit set to occur.

Melon Pests

  • Aphids and spotted and striped cucumber beetles will attack melons.
  • Hose away aphids with a blast of water or pinch out infested foliage.
  • Handpick and destroy cucumber beetles promptly; they can transmit cucumber bacterial wilt to melons. You can also dust or spray adult beetles with rotenone or a pyrethrum-based insecticide.

Melon Diseases

  • Melons are susceptible to wilt, alternaria leaf spot, stem blight, powdery and downy mildew, and root rot.
  • Plant disease resistant varieties.
  • Keep the garden clean and free of weeds and plant debris that can harbor pests and diseases.
  • Remove and destroy disease infected plants immediately.
  • Bacterial wilt is spread by cucumber beetles.
  • Bacterial wilt and stem blight will cause melons to suddenly wilt and die.
  • Control cucumber beetles as soon as they appear.
  • Powdery mildew and downy mildew are fungal diseases that will cause melon leaves to turn gray-white late in the season. Protect leaves against fungal disease by spraying with compost tea or a solution of 1 part skim milk to 9 parts water.
  • Select disease resistant varieties.
  • Improve air circulation by spacing plants properly.

Harvesting Melons

  • Cantaloupes will be ready for harvest 70 to 100 days after sowing.
  • Most melons on a single plant will come to harvest within a 3 to 4 week period.
  • Limit water for a week in advance of the harvest to concentrate fruit sweetness. Too much water will dilute the sugars in the fruit.
  • When muskmelons reach full-size rinds change from green to tan or yellow and stems turn brown they are ready for harvest. The skin under the netting will turn yellow-brown when the fruit is ripe and the netting will become more pronounced
  • Smooth-skinned honeydew melons will become cream-colored when ripe.
  • A ripe melon will develop a circular crack where the stem attaches to the fruit.
  • Ripe melons will have a sweet aroma at the stem end.
  • Ripe melons will slip easily off the stem; a half-ripe melon will require more pressure and may come off with half the stem attached.
  • Harvest melons when they are dry.
  • A ripe melon will soften after harvest but it will not continue to sweet off the vine.
  • Leave melons on the vine until they are ripe.

Storing and Preserving Melons

  • Melons will keep in the refrigerator for up to one week, but sweetness and flavor may diminish.
  • Melon slices or balls can be frozen or pickled.

Muskmelon (Cantaloupe) Varieties

  • Early Season: ‘Alaska’ (65-80 days); ‘Canada Gem’ (78 days); ‘Earligold’ (73 days); ‘Early Hanover’ (80 days); ‘Magnum’ (80 days); ‘Primo’ (79 days); ‘Pronto’ (80 days); ‘Pulsar’ (80 days); ‘Solid Gold’ (80 days); ‘Sweet Granite’ (80 days); ‘Sweet ‘N Early’ (75 days).
  • Midseason: ‘Ambrosia’ (86 days); ‘Delicious’ (83 days); ‘Edisto’ (88 days); ‘Four-Fifty’ (90 days); ‘Grande Gold’ (88 days); ‘Hale’s Best’ (86 days); ‘Imperial’ (90 days); ‘Pike’ (85 days); ‘Pulsar’ (86 days); ‘Roadside’ (90 days); ‘Super Market’ (90 days); ‘Superstar’ (86 days).
  • Late Season: ‘Edisto’ (95 days); ‘Hearts of Gold’ (95 days); ‘Iroquois’ (90 days); ‘Kansas’ (90 days); ‘Saticoy’ (90 days); ‘Top Mark’ (90 days).
  • Large: ‘Old Time Tennessee’ (90 days).
  • Space Savers: ‘Bush Star’ (80 days); ‘Jenny Lind’ (75 days).

About Muskmelons and Cantaloupes

Muskmelons differ from true cantaloupes:

  • A muskmelon is round with a yellow-tan netted rind. A muskmelon has salmon, white, or green flesh and weighs 2 to 3 pounds (.9-1.3 kg). Muskmelons are very sweet to taste and have aromatically perfumed flesh
  • A true cantaloupe is oval or globe-shaped with a hard, rough, scaled or warted-rind (not a netted skin). The flesh can be gray-green, yellow-tan and orange, or salmon-orange. A true cantaloupe weighs about 2 pounds (.9 kg). It is sweet tasting and aromatic
  • The muskmelon or cantaloupe is a long trailing annual plant.
  • Botanical name: Cucumis melo
  • Origin: South Asia, tropical Africa