Melons

Tina Lee

There’s nothing like the sweet smell of a ripe melon that you’ve just pulled from the vine. Melons thrive on warm weather and full sun. However, if you live in an area where the summer temperatures tend to be on the cool side, you’ve probably been disappointed trying to grow the heat-loving melons at home. Many people who live in Cupertino and other cities on the northern end of the peninsula, do not try to grow melons because summer nighttime temperatures can drop into the 50s and result in small 2-3 inch melons that are not very sweet. For the 2000 McClellan Ranch vegetable research trial in Cupertino, the Master Gardeners took on the challenge and proved that using a combination of special varieties and growing techniques can indeed result in a successful melon harvest for cool weather climates.

Melon Varieties
We specifically chose early ripening melon varieties so most of the melons could be harvested after 70-85 days. We also picked varieties that were developed to grow well in difficult cool weather areas such as northern, coastal, or mountain climates. We grew 20 different varieties of melons that belonged to the following categories:

• Butterscotch: Orange and green flesh with a very sweet butterscotch taste
  
• Casaba: Oblong melons with a wrinkled, bright yellow rind and pale green flesh
  
• French Charentais: Small French melon with a sweet, aromatic orange flesh
  
• Galia: Israeli melon with sweet, green flesh with a banana-like aroma
  
• Honeydew: Flesh can be green, white, or orange with smooth, white skin
  
• Muskmelon: Familiar American cantaloupes with orange flesh and netted skin
  

Melon Trial Ratings
From the results of the taste trials, two muskmelons came in at the top of the ratings. Earliqueen ranked first with the highest sugar content and a medium firm texture. Burpee F1 Hybrid rated a close second with a sweet flavor and a slightly softer texture. Galia, an Israeli melon, also ranked highly with a green flesh that exuded a perfumed aroma and sweetness. Honey Pearl was the only honeydew to make it into the top-five list with a sweet, white flesh and crisp texture. Tropical Galia Passport, another melon from the Middle East, had very thick green flesh, a small seed cavity, and a pleasant fragrance.

Growing Melons in Small Spaces
If you have a small garden plot or only do container gardening, you’ve probably given up on the idea of growing melons since the vines take up so much space. However, there is a miniature variety called Minnesota Midget that we tested in the trial that you can try. Because the vines only grow 3-4 feet long and the average fruit size is 4 inches in diameter, Minnesota Midget is the perfect size for trellising and container growing. You can support the fruit on a trellis by using nets made of old stockings or onion bags.

Melon Test Garden Results
We made two rows of mounded beds in the plot and buried soaker hose lines along the sides of the beds for irrigation. Then we covered the beds with an infrared transmitting (IRT) plastic mulch film to warm the soil. On May 13th, we cut slits in the plastic mulch film and planted the melons 18 inches apart on center. In an effort to have the melons ripen at the same time, we direct-seeded the varieties that matured before 80 days and used transplants for the varieties that took longer than 80 days. We mixed in some soybean meal into the planting holes as additional fertilizer to the nitrogen that was already present from the winter fava bean cover crop and manure that had been tilled into the soil. Then we placed a floating row cover on top of the mounds to warm the air over the soil and protect the plants from wilt-carrying striped cucumber beetles.

We found that the special IRT mulch raised the bed temperature 5 degrees above the surrounding soil. The floating row cover also helped keep the seedlings warm and get off to a good start. However, we had an expected heat wave in late May and did not remove the row cover. The temperature rose too high under the row cover and killed some of the plants.

We only watered the beds using the soaker hoses about 3-4 times throughout the whole growing season because the IRT mulch made the soil retain its moisture. Nevertheless, we found that even that small amount of watering was too much and resulted in some of the melons losing their flavor and tasting bland. After the fruit had set, we chose to trim back the vines for maintenance so the vines wouldn’t grow out of control all over the plot. In general, however, the melon vines do not have to be tipped back. The plants will only set the amount of fruit that they can handle.

We removed the row covers when the plants began to flower to permit pollination. Then we sprinkled diatomaceous earth on the leaves to protect the plants from the cucumber beetles. During August, many of the plants became diseased with powdery mildew. We should have sprayed with wetable sulphur to control the disease but did not get to the plants early enough.

The biggest problem we experienced was determining when the melons were ripe so we could harvest them at the correct time. The varieties with netted skin such as the muskmelon and Galia types were easy to tell when they were ripe because the fruit pulled off easily or "slipped" from the vine. However, the varieties with smooth, harder skins such as honeydews or casabas do not slip and must be cut from the vine. We learned that the skins of these varieties actually feel hairy when the fruit is not ripe. As the fruit matures, the skins become smooth and slippery. When the fruit is fully ripe, the skins change again to have a waxy feel.

Unfortunately, because we weren’t experienced in knowing when to harvest the melons, we picked some of the smooth-skinned melons too early before they were ripe. In addition, we did not have a public tasting because the melons all ripened at different times and they did not store well after they were harvested. We held our own tasting on August 12th for the early ripening varieties and another tasting on August 26th for the late ripening varieties.

Although we had problems with picking the melons correctly, we were very pleased with the high yield of fully mature melons that we harvested from the trial. Before this trial, gardeners at McClellan Ranch had never been able to successfully grow melons past the 2-3 inch size.

Melon Species
Melons belong to the Cucurbitaceae or gourd family that also includes cucumbers, gourds, pumpkins, and squash. Members of the gourd family have annual vines with yellow or white flowers and large, fleshy, seedy fruits. Melons thrive on warm weather and full sun and usually require a substantial amount of growing space for the vines to spread out.

Planting Recommendations for Cool Weather Climates
To maximize your chance for successfully growing melons to full maturity, look in seed catalogs and choose early ripening varieties specifically developed to grow well in difficult cool weather areas such as northern, coastal, or mountain climates. Early May is the best time to direct-seed melons. You can also start the seeds indoors in April and then transplant the seedlings when they have two or three true leaves. Don’t try to start the seeds indoors much earlier than April because the seedlings grow very quickly and do not transplant well once they become large and rootbound. The seedlings don’t like having their roots disturbed so be very careful during transplanting.
Amend the soil with plenty of compost and well-rotted manure. Use raised or mounded beds and lay drip irrigation lines or soaker hoses down the center of the beds. Then cover the beds with infrared transmitting plastic mulch film or plain black plastic mulch to warm the soil. Cut slits in the plastic 18 inches apart down the center of the beds and plant the seeds or seedlings.
Immediately cover the beds with floating row covers to warm the air over the soil and protect the plants from wilt-carrying striped cucumber beetles. However, if the weather starts to get too warm, be sure to remove the row covers or the plants will overheat and die. Also, remove the row covers when the plants begin to flower to permit pollination. Once the row covers are removed, sprinkle diatomaceous earth on the leaves to protect the plants from cucumber beetles. To prevent powdery mildew, spray the leaves with wetable sulphur during late summer when the nights begin to cool down.
Melons need plenty of water to support quick vine growth in early summer but the plastic mulch will cause the soil to retain moisture so check the soil under the plastic to see when watering is required. Once the first fruit ripens, stop all watering. Too much water at ripening time dilutes the fruit’s sugars and ruins the sweet flavor. The melons don’t need the water because they develop a deep root system soon after they start to flower.

Harvesting
Don’t harvest your melons until they are fully ripe. Melons will get softer after they are picked from the vine but they will never get sweeter. Varieties with netted skin such as the muskmelon and Galia types are easy to tell when they are ripe because the fruit pulls off easily or "slips" from the vine. However, varieties with smooth, harder skins such as honeydews or casabas do not slip and must be cut from the vine. The skins of these varieties actually feel hairy when the fruit is not ripe. As the fruit matures, the skins become smooth and slippery and some varieties change color. When the fruit is fully ripe, the skins change again to have a waxy feel. In addition, the blossom end should have a ripe, fruity smell.

Using Your Melons
After you harvest your melons, there are many ways to enjoy them. Melons aren’t just for breakfast anymore. For an easy appetizer, wrap slices of any type of melon with prosciutto or dry salami. Melon cubes or balls are great in fruit salads and for a refreshing treat, squeeze fresh lemon or lime juice over melon wedges. Melons also make a delicious dessert. Top slices with vanilla ice cream, sprinkle with chopped crystallized ginger, or drizzle with hazelnut or orange flavored liqueur.

Melon Trial Ratings

Bibliography
Ogden, Shepherd. Step by Step Organic Vegetable Gardening. New York: HarperCollins Publishers, Inc., 1992.
Sunset Editors. Sunset Fresh Produce. Menlo Park: Sunset Publishing Corp., 1987.
Sunset Editors. Sunset Western Garden Book. Menlo Park: Sunset Publishing Corp., 1988.

Melon Volunteers
Ralph Riddle headed the project for the group of melon volunteers that included Roxanne Beverstein, Penny Cheney, Ralph Eddy, Pat Enfantin, Fran Grabau, Eve Hanson, Tom Jow, Bill Michael, Jean Lee, and Tina Lee.