A black tarp or black plastic traps heat so that the soil is warm enough to encourage growth at the beginning of the season. It also keeps vines clean and helps prevent diseases that may live in the soil.
The rind of a honeydew melon is cream colored and the inside is light green when the melon is ripe.
Keep foliage healthy because it is the source of sugar for the fruit. As melons ripen, the leaves naturally begin to look rough.
As cantaloupe ripens, the skin under the netting turns a yellow buff color.
This cantaloupe is nearly full size but not quite ripe. The skin color under the netting is still green.Homegrown cantaloupe and honeydew offer an explosive taste that doesn’t compare to their store-bought cousins. The key is plenty of moisture, sunlight, and heat. Melons demand two to three months of heat, which makes growing them in northern regions challenging, but not impossible. By using black plastic mulch or a black tarp to warm soil and floating row covers to trap warm air near plants, gardeners in any part of the country can count on cutting into the homegrown goodness of melons. These sun-ripened fruits pack plenty of vitamin C and antioxidants into every bite, combining great taste with great nutrition.
Soil, Planting, and Care
Cantaloupe and honeydew thrive in warm soil. Don’t plant until the ground temperature is above 70 degrees F, which typically occurs about the time peonies bloom in northern zones. Prior to planting, cover soil with plastic film to hasten soil warming.
Because cantaloupes and honeydew are heavy feeders, prepare your planting bed by adding seaweed, compost, or rotted manure. If you live near a horse farm, another option that works well is to excavate the soil 1 foot deep, add a 9-inch-thick layer of fresh manure, and then cover that with 3 inches of soil mixed with compost. This creates a bed with a high-nitrogen soil base that is naturally warm because it generates a little heat as the manure composts. In yet another approach, some gardeners plant melons atop their compost piles to ensure a warm footing and adequate nitrogen.
Melons need room to roam. Space transplants 12 inches apart in rows 4 to 6 feet apart. Or, to save space, plant melons 12 inches apart at the base of a trellis. When trellising melons, tie vines to the trellis daily, using soft plant ties that won’t crush stems. A trellis for cantaloupe should be large: up to 8 feet tall and 20 feet wide in warmest climates.
Trellising offers several advantages. Vines get better air circulation than on the ground, which reduces the chances of disease. In northern zones, vines also get more sunlight when on a trellis that’s positioned at a slant toward the sun. You can also place a trellis against a bright reflective surface, which increases the amount of light reaching leaves and confuses melon aphids, who like to hide on the shadowy undersides of leaves. If you use a trellis, anchor it firmly so gusty summer winds don’t topple the vine-covered trellis. Hold ripening fruit using slings made from netting, nylon hose, or mesh bags.
After transplanting in spring you can cover plants with floating row covers to exclude insects and trap warm air near plants; this is most important in cooler climates but is useful everywhere to keep certain pests off the plants.
Vines bear male and female flowers. Male flowers open first, joined by female blossoms about a week later. Female flowers have a small swelling at the base of the flower. When vines start to bear male and female flowers, remove row covers.
Tackle weeds before vines start to run, because at a later stage it will be difficult to move among vines without crushing them. Mulching soil under vines suppresses weeds and slows moisture evaporation from the soil. Of course, if you planted in black plastic, that is already done.
Water may be the most important variable that you supply; melons need a steady supply. Vines are most sensitive to drought during the time between transplanting and when fruits start to form. Keep soil consistently moist but not waterlogged, which will kill plants. It’s typical for leaves to wilt under midday sun, but they shouldn’t remain wilted into the evening. If possible, avoid overhead watering. Soaker hoses deliver water directly to the soil, preventing possible spread of fungus diseases on wet foliage. If you must use a sprinkler, then water vines very early in the morning so that leaves can dry early, which helps prevent fungus diseases.
For vines running on the ground, keep fruit from direct contact with soil to prevent rot and protect fruit from pests and rodents. Place ripening fruit on mulch, upturned coffee cans, or flower pots. If large critters such as groundhogs discover your melons, protect ripening fruits by covering them with plastic milk crates or similar boxes weighted down with a few bricks.
Some gardeners like to switch fertilizer during the course of the growing season. During the time between transplanting and when the first flowers open, use a fertilizer with more nitrogen than phosphorus and potassium. Once flowering begins, use a fertilizer with less nitrogen and more phosphorus and potassium, such as African Violet Food or liquid seaweed.
An old garden adage suggests pinching off a vine’s growing shoots as melons start to ripen to cause the plant to divert all its energy to the ripening fruit. Research has proven this false. The vine needs all its leaves to produce the sugars that sweeten fruit. Anything that reduces the total number of leaves available for sugar production reduces melon sweetness.
The more fruits that ripen at the same time, the less sweet they’ll be, since the vine will have to divide the leaves’ sugar production between fruits. In warmer climes with a long growing season, experienced growers often prune off all but one newly forming melon every 2 weeks. Ripening 1 melon at a time yields maximum sweetness. As you gain experience, you’ll develop your own technique.
In colder regions, remove any blossoms that start to develop within 50 days of your area’s first average frost date. This ensures remaining, larger fruits will ripen before frost.
Troubleshooting
The key to a sweet melon is lots of sugar, which is made by the leaves. So anything that hurts the leaves also hurts the quality of the fruit. Be on the lookout for fungus diseases, which spread rapidly. Alternaria leaf spot and gummy stem blight produce spots on leaves, while stem blight also forms bleached or tan sections on stems and rot on fruit. Downy mildew causes yellow or pale green leaf spots, while powdery mildew produces white spots on leaves. Treat fungus diseases with fungicides. Check with your local garden center or Extension agent to learn which fungicides are approved in your state and more about the disease you’re fighting. Ambrosia cantaloupe is tolerant to powdery mildew.
Melon aphids can quickly colonize a vine, so inspect leaf undersides daily. If you spot aphids, treat them with insecticidal soap.
Spotted and striped cucumber beetles can attack vines, transmitting bacterial wilt disease, which causes vines to collapse. Infected vines don’t recover. Treat adult beetles with rotenone or a pyrethrum-based insecticide; apply at dusk to avoid harming honey bees.
Harvest and Storage
Melons typically ripen over a short period of time, up to 3 to 4 weeks for cantaloupes. As soon as 1 melon is ripe, the others won’t be far behind. About a week before a melon is ripe, minimize watering to just enough to keep vines from wilting. This lets vines concentrate sugars in the fruit. Too much water dilutes the sugar and, of course, the sweetness.
You can judge a cantaloupe’s ripeness by skin color and stem. The rind of a cantaloupe changes from gray-green to yellow-buff, and the netting pattern becomes more pronounced. At the stem, a crack appears that encircles the base of the stem. A ripe melon should slip right off the vine. Cantaloupes also develop a musky odor that’s noticeable as you approach the melon patch.
The smooth-skinned honeydew melon becomes cream colored when ripe, and the blossom end should give slightly when pressed. Avoid pressing the blossom end repeatedly as you try to gauge ripeness. Excessive pressing can lead to bruising, which gives a false read on ripeness. To harvest a honeydew you don't plan to use immediately, leave about an inch of stem attached to keep the melon from rotting.
Store melons in the refrigerator for up to a week. If you have extra melons on hand, dice or cut the flesh into balls and freeze for slushies or cold soup.