I have written a couple of posts about growing melons, so go to those links for the basics. Here I am going to dive deep into tips for increasing your success by paying attention to the details. I dove so deep I made two pots. part 2 will follow in a couple of weeks.
I wrote a post, Fruit for the Month: July, in my monthly series about small fruits that can be grown sustainably in a mid-Atlantic climate, with melons as the focus. In our climate, July is the month to start harvesting muskmelons (often called cantaloupes), Asian melons, and canary melons. Watermelons are slower to ripen.
Basic needs for success with growing melons
Melons love warm, sunny days and need 80-100 days from seed sowing to harvest. For good production, melons need warm weather, along with a steady supply of water. Melon plants also need good air circulation, so leaves and fruit can dry fairly quickly after dew or rainfall. To help prevent the spread of diseases, rotate crops and avoid growing them where other cucurbits were planted in the previous year or two.
Melons thrive in well-drained soil, sandy loam, or in clay soils that have been good levels of organic matter, so long as they get plenty of sunshine and warmth. Soil pH should be 6-7 for healthy melons and good yields. Encourage drought-resilient crops by using drip irrigation, so that roots grow deep. Look for resistance to diseases you know to be a problem in your area.
They have no frost tolerance. Vines can sprawl and cover a 4’ (1.2 m) bed, or fill even a 7’ (2.13 m) row when grown on the flat, and for a longer harvest from each planting, do not crowd them.
Melon seed specs are the same as cucumbers for size and weight: 1000 seeds/oz, 36 seeds/gm. 0.5oz sows 100′, 6 oz/1000’ at 6 seeds/ft. (100 seeds, or 11gm/m at 2.5 cm spacing.). Melon yields will be affected by irrigation during fruit development, but not by watering levels during vegetative or flowering stages. Adequate water is especially important in the seedling stage and during fruiting. Marketable yields of muskmelons can be 7,000-10,000 fruits per acre (17,500-25,000 per hectare) when grown on plastic mulch, and down to half that on bare ground. Most melon plants will yield 3 or 4 good melons.
Types of melons
Cucumis Melon Varieties
Jeff McCormack of Saving Our Seeds distinguishes 8 types of Cucumis melon:
- Cucumis melo reticulatus Muskmelons (which we commonly call cantaloupes) are in this group. They have orange or green flesh and usually have netted skin. They slip from the vine when ripe (perhaps with a nudge).
- True cantaloupes, Cucumis melo cantalupensis, are rare in the US. They are rough and warty rather than netted. Fedco Seeds sells Prescott Fond Blanc and Petit Gris de Rennes. Charentais melons are true cantaloupes. They are smaller, round, good-flavored orange-fleshed melons. I have successfully grown 78-day Savor, a 2lb (0.9kg) melon with a green-grey skin and deep orange flesh.
- Cucumis melo inodorus is the group of winter melons: Casabas, Crenshaws, Honeydews and Canary melons. They have a smooth rind, no musky odor, and they must be cut from the vine – they will not slip. Crenshaw melons are large oblong 78-day melons with light yellow skin and very aromatic pale creamy orange flesh. Canary melons are smooth yellow 4lb (1.8kg) fruits with white flesh and are quite sweet.75 days to maturity. We have had good success with Mayor. Honeydew melons are fast-maturing, smooth skinned oval melons, usually with pale-green flesh, although Honey Orange is salmon-colored. 3lbs (1.4kg), 74 days.
- Cucumis melo dudaim includes Plum Granny and Queen Anne’s Pocket Melon, grown for aroma, not flavor.
- The four groups less-common in the US are m. flexuosus (snake melons including Armenian cucumbers), C. m. conomon (Asian and Oriental pickling melons), C. m. chito (mango melon and others named after other fruits), C. m. momordica (snap melons).
Of these types, we mostly grow muskmelons. Externally, they turn beige and slip from the vine when ripe. They have a yellowish-buff skin with a raised netting, and sometimes lengthwise sutures (ribbing). They have soft sweet orange flesh, with a complex sweet aromatic flavor, and the 3–7lbs (1.5–3kg) fruits take 75-84 days to mature. They are sometimes divided into two types: Eastern varieties are sutured (scalloped in shape) and can have a very short shelf life, while Western ones are typically not sutured but are netted (covered with a corky mesh of lines), and they will usually hold for two weeks after harvest. I see many netted and scalloped melons, so I don’t use this classification.
Kansas (90d from transplanting) is an heirloom muskmelon with excellent flavor, fine texture and enough sturdiness to stand up to humid weather and variable rainfall. The 4lb (1.8 kg), oval fruits are sutured and moderately netted. They are hardy, productive, with good resistance to sap beetles that can destroy fruit of other varieties. They ripen almost all the way out to the rind (not much waste!). Pick these at full slip, and be sure to inhale the aroma at the stem end, as you carry them to the table.
Pike (85d) (see photo at top of the post) was bred for growing in unirrigated clay soil. It is vigorous, high-yielding, disease-resistant and (depending on irrigation) it produces 3-7lb (1.4-3.1 kg) fruits with great flavor. We have also had success with Edisto 47 (88d OP) about 6-7″ (15-17 cm) in diameter. With resistance to ALS, PM, and DM, it exceeds the disease resistance of many hybrids. Hales Best has also done well here. For Downy mildew resistance, tolerance to cucumber beetles, and great flavor, grow Trifecta from Commonwealth Seeds and Southern Exposure Seed Exchange.
Other melon types
The University of Kentucky has a publication on specialty melons.
Fastest to produce a crop are the 65-day Asian melons such as Torpedo (replaced Sun Jewel), or Early Silver Line. A good type for people with short growing seasons, provided you can make a warm spot for them. These 1-2lb (0.5-1kg) melons have refreshing crisp white flesh and are pleasantly sweet without over-doing it. The long oval fruits average 7″ x 3 1/2″ and are pale yellow with shallow white sutures (“seams”). Some people disparage them as “cucumber melons,” but their good points are earliness, tolerance of chilly weather, being easy to grow and having a pleasant flavor. They ripen to a more buttery yellow and slip off the vine when ripe. Plants are resistant to downy and powdery mildews, and can be very productive. We buy seed from Johnny’s Selected Seeds.
Galia tropical melons have green flesh, yellow-tan skins and a round shape.
I wrote a post for Mother Earth News Organic Gardening Blog about personal size melons, something we tried for a couple of years. These “individual serving” melons weigh about 2-2.5 lbs (1 kg) each, compared to standard cantaloupes at 3-6lbs (1.5-2.5kg) each. To serve, just cut in half and scoop out the seeds. Add ice cream if you like. We tried Tasty Bites (they top out at 3lbs/1.4kg) and Sugar Cube 2–2 1/2 lb (1kg). The advantage of having a smaller fruit was not more than the disadvantage of harvesting smaller fruits for us.
Sowing melon seeds indoors
More and earlier success comes with sowing melon seeds indoors, where the right temperatures can happen earlier in the year. Melons are a bit finicky in their youth, but given a strong start, they can do very well. Melons need slightly warmer temperatures than cucumbers. The seeds take 8.4 days to emerge at 68°F (20°C), 4 days at 77°F (25°C), and 3.1 days at 86°F (30°C).
Cucurbits are not very easily transplanted, so choose a method that minimizes root damage, such as soil blocks, Winstrip trays or 2” (5 cm) deep cell flats that are easy to eject plants from. Sow 2-3 seeds per cell 0.5” (1 cm) deep.
Sow 3-4 weeks before you intend to plant out: we sow our first melons 4/15 to transplant with hoops and rowcover 5/6, which is a week after our last frost date. Temperatures below 45°F (7°C) can stunt growth. If the spring is cold, just wait it out. Melons will do OK with fluctuating temperatures, provided they are not too cold.
After germination, the temperature should be reduced to 75°F (24°C). We always ensure our melons get a spot in the greenhouse with very good light and no drafts.
Keep the soil moist and when seedlings have reached 2” (5cm) in height, single them (thin to one plant per cell) by cutting off weak seedlings at soil level, leaving one strong seedling per pot or cell. Keep temperature above 70°F (21°C) during the day and 60°F (16°C) at night.
Once the first true leaves appear, lower the temperature to 65°F (18°C) and reduce watering a little. Cucurbit seedlings are sometimes damaged by foliar sprays, especially ones including soaps, so avoid killing by mistaken kindness.
Harden off the plants for a week, by reducing water, before you set them into the garden. Set them outside in a shady area on warm days, gradually increasing the time outside each day from one hour to two hours, to three, and so on. Alternatively, use shadecloth and increase the sun exposure by an hour a day.
If you want a faster harvest than you’d get from direct sowing, but you don’t want to do transplants, you can chit (pre-sprout) the seed. Put the seed on damp paper towels, roll them up and put the bundles in plastic bags loosely closed, or plastic sandwich boxes, not sealed. Keep at 70-85°F (21-29°C). Check twice a day (this also introduces fresh air to the seeds), and sow before the root reaches the length of the seed. Seeds which are already sprouting will not need more watering after sowing until the seedlings emerge, unless the soil is dry as dust.
Stephen Albert writes the very informative Harvest to Table website, which includes step-by-step details on pre-sprouting melon (and other) seeds. It takes only a few days, and gets the tiny seedling through the tough seed coat. How to Plant and Grow Melons
Direct sowing of melon seeds
For sowing in open ground wait until the soil temperatures is 59°F (15°C), the minimum to germinate melon seeds. We make a furrow 0.5-0.75” (1.3-1.8cm) deep, water the furrow if the soil is dry, put one seed every 6” (15 cm), pull the soil back over the seeds and tamp down. Growers commonly space seeds at 2” (5cm), but using the wider spacing gives us no problems, and uses less seed. We cover all our early cucurbit sowings with rowcover until the plants start to flower (about a month) as we have many pests and diseases. Later sowings get ProtekNet insect netting rather than rowcover. When the plants start to flower, we remove the covers, hoe and thin to 18-24” (45-60 cm). Melons can use 7.5-15 ft2 (0.7-1.4 m2) each on plastic mulch, and double that space on bare ground. Melon rows are typically up to 6-10’ (2-3 m) apart.
It is possible to sow cucurbits through plastic mulch by jabbing holes in the plastic and popping the seeds in. This method leads to earlier harvests, as the mulch warms the soil, and there will be no weeds.
For a main crop, we direct sow 5/25 and 6/25. Maximum germination temperature is 100°F (38°C).
Melons are admittedly delicate to transplant. Wait for the right conditions and take great care when handling the plants.
Check your local weather forecast to ensure that your melon plants will not be subjected to chilly, windy conditions when they are newly transplanted. Warm overcast conditions late in the day are best for transplanting, and rowcover (preferably on hoops to reduce abrasion) can be used to provide warmer and less breezy conditions.
Before starting transplanting, check the soil temperature: the soil should be at least 70°F (21°C) for melon survival. Melon plants exposed to temperatures cooler than recommended might not set fruit later on. One way to speed up soil warming is to cover the area with black plastic mulch for 1-3 weeks prior. Cut an x-shaped slit where for each plant and hold the edges of the plastic down with rocks. We space our melons at 2’ (60cm) apart in the row, with rows 6’ (2m) apart.
To help reduce transplant shock, water the flat (or pots) well the day before and again one hour before transplanting. Avoid disturbing the roots when transplanting. Cucurbit transplants are often leggy, and they should be planted so that the entire stem up to the base of the leaves is below soil level, otherwise the fragile stem is liable to get broken. The stems will do better protected in the ground. Water the soil thoroughly. If you are not using plastic mulch, hoe as needed for a few weeks, and wait until hot weather before spreading organic mulch (straw, spoiled hay or dry tree leaves), as this keeps the soil cool, and as I stressed already, melons like heat. Depending on soil fertility, you may want to add fish emulsion to encourage growth.
Another tip for protecting transplants against insect damage is to mix up a kaolin clay soup, invert the plug flat and dip the upside-down plants in the liquid before taking them to be transplanted. Three cups to one gallon of water make up into a suitably thick mix for this technique. Surround is the best-known brand. You can also spray the plants during their growth, with Surround. This does wash off if it rains or you use overhead irrigation, and you will need to reapply (or switch to netting if the plants are not yet flowering.)