Melons are classified as cucurbit (Cucurbitaceae) vegetables. The cucurbit family includes cucumbers,  summer squash (zucchini), winter squash (hubbard, acorn, spaghetti, butternut, delicata), pumpkins, melons, and gourds. 

Since all of these plants share a common ancestor, they all have very similar growing needs and are prone to similar problems.

While they are quite similar, there are some key differences, so to ensure best success so we've broken these into separate articles for easier instruction.

1. Watermelons are native to South Africa while cantaloupe and muskmelon are native to the Middle East.
2. In some dry, hot regions, watermelons were used or cultivated as a source of water.
3. Seeds of watermelons were found in King Tut’s tomb.
4. Seeds of muskmelon have been used medicinally to reduce cough.
5. Cantaloupes are named after Catelupo, Italy where they were cultivated in the 1700’s.

Sources:

Cantaloupe Fact Sheet. (n.d.). United States Department of Agriculture and Wisconsin Department of Public Instruction.

Paris, H. S. (2015). Origin and emergence of the sweet dessert watermelon, Citrullus lanatus. Annals of Botany, 116(2), 133–148.

Melons are high in Vitamins A and C as well as fibre.  Click for detailed information about  cantaloupe and watermelon  from the USDA National Nutrient Database for Standard Reference. 

The Canadian Food Guide recommends that roughly half of the food on your plate should be fruits and vegetables.

Melons are a warm season plant that need between 52 and 85 days to maturity. They can be seeded directly into the garden once the soil is very warm (at least 18°C, but even warmer is better), usually about 2 weeks after your plant out date. Direct seeding works on the prairies, so using seedlings is not necessary.

If you live in the far north, you can grow melons as seedlings. Seedlings can sometimes also be purchased from a local greenhouse.

Starting your own melon plants from seed

• Melons do not like root disturbance from transplanting, so it's important not to start seedlings too early. Seedlings should only be 10-14 days old before planting out (cotyledons have emerged along with only one or two true leaves).  Larger transplants will experience transplant shock when they are planted outdoors: plants will not grow for several weeks (or at all) depending on the level of transplant shock they experience. See our video below.
• Start seedlings about 2 weeks prior to transplanting out. You can transplant seedlings as soon as daytime and nighttime temperatures are warm at least 18°C, about 2 weeks after your last average frost free date. For example, in Wollaston Lake (northern Saskatchewan) your plant out date is June 5, so start your seedlings around the first of June for planting out around June 20.
• Jiffy-7's are good for sowing seeds because there is less root disturbance when planting. Soak the Jiffy-7's for 20 minutes in warm water to fully hydrate and expand them. Once they are planted, cover with plastic or a dome and do not water. Remove the plastic once seeds have germinated. 
• Another way to reduce root disturbance is to use home-made newspaper pots or peat pots. Fill them with a soil-less mix that contains peat or coir and vermiculite and/or perlite. (Both of these types of pots can be planted directly in the soil, but be sure to bury the rim of these pots. Otherwise the rim acts as a wick and will dry out your seedling.)
• Sow 2 seeds 1 cm deep per JIffy-7 or container and then thin to the strongest plant after they have grown their first set of true leaves. 
• Melons prefer warm soil. At 24°C, seeds will germinate in 5 or 6 days. Use a heat mat if you have one, or place pots in a warm spot like the top of the fridge for germination.
  
• Take care not to over water your seedlings. Soil should be moist like a damp sponge, but not soggy.
• Place seedlings under lights after germination, which is crucial for the growth of healthy seedlings. seedlings require a minimum of 14 hours of light each day.
  
• Leave a fan blowing on your young seedlings as they grow to help to grow heartier plants and to reduce some seedling diseases. Research has shown that stem diameter can be increased by providing seedlings with constant air movement from an oscillating fan – or by lightly brushing seedling tops with a tea towel or stick at least 20 times daily.
• For more details, check out our article on growing your own seedlings.

The ideal melon transplant:

• has no more than two sets of true leaves. The first leaves that grow are not true leaves. They are "seed leaves" called cotyledons and are round. All leaves that grow after these are true leaves.
• is dark green in color.
• has a good root system but is not root-bound (tight, hard ball of roots) or has lots of roots growing out of the Jiffy-7.
• has a stem that is strong and sturdy. The internodes (spaces between leaves along the stem) will be small.  seedlings that are too tall will tend to break and dry out more easily once planted out into the garden.
• Fertilizing recently planted seeds or young emerging seedlings is not recommended. Start fertilizing a few days after they have been planted out in the garden using 20-20-20 water-soluble fertilizer once or twice a week. Mix according to label directions.

Harden off seedlings prior to planting out by moving them outdoors into a sheltered, frost-free location at least 3 days prior to transplanting.

Don't forget to label what you planted. It's also helpful to draw a map to help you track planting locations and success each year. This information is critical if you're rotating your crops to help prevent insect and disease issues.

Timing

• Melons may be direct seeded in the garden on the prairies or planted as seedlings in the far north. See our transplants tab for tips on growing or purchasing your own transplants.
• You can transplant seedlings 2 weeks after your plant out date or last average frost date for your area. For example, in Wollaston Lake (northern Saskatchewan) your plant out date is June 5, so start your seedlings around the first of June for planting out around June 20. 
• Transplants must be hardened off before transplanting outdoors. Melons do not tolerate cool soil or air temperatures at all and can be set back or stop growing as a result.
• Whether you are direct sowing or planting seedlings, ensure the soil is very warm. Prewarm soil about 2 weeks before you seed by covering it with a sheet of clear plastic. Studies show that clear plastic warms soil better than black or other colours of plastic. Secure the edges. Remove the plastic before sowing seeds.

• Sow 3-4 seeds 2 cm (1″) deep and 25 cm apart within the row. Thin to the strongest seedling. 

Planting instructions for seedlings

• When planting, cover the entire transplant “plug” or seed ball with soil to prevent the plant from drying out.  If using newspaper pots or peat pots, make sure they are quite moist before planting and remove the rims of the pots. Exposed rims, peat or coir within the plug will act as a wick, drawing water away from the transplant and drying out the root ball. 
• Try not to disturb the roots when planting.
• Seedlings should be spaced 90 cm (3') apart within the row, allowing 90 cm (3') between rows for bush varieties. For vine varieties of melon, space 1.8 m (8') apart within the row and between rows.
• Water the transplants in with 10-52-10 soluble fertilizer, mixed according to the directions on the label. This is only done once, to encourage good root development. See the "Care Once Planted" tab for how to fertilize for the rest of the growing season.

Cutworm prevention

If you have had cutworm problems in your garden, place a collar around your seedlings right after planting. Make collars out of toilet paper rolls, or any tin can or plastic container such as a yogurt container with both ends removed. Insert the collar at least 5 cm in the ground to prevent cutworms from feeding on the stems of your seedlings.

For best results on the prairies and in the far north, choose cultivars that need less than 70 days to maturity.

Here are cultivar recommendations from the North Dakota State University Cultivar Trials, as they share a similar prairie climate and soils. You may download their list here:North Dakota State University Vegetable Cultivar Recommendations for 2021

• Watermelon
  • Seeded: Petite Yellow, Sangria, Stargazer, Sugar Baby, Sweet Dakota Rose, Yellow Doll
  • Seedless: Millionaire
• Muskmelon
  • Aphrodite, Athena, Goddess, Solstice, Superstar. Specialty: Arava, Earli-Dew, Passport, San Juan.

The following cultivars are recommendations from the University of Saskatchewan vegetable program field trials which were conducted from 1989 through 2016. Although this information is no longer current, some may find it useful.

• Watermelon
  • Red flesh: 8203RWT, Black Jade, Bo Wong, Compadre, Crimson Early, Crimson Sweet, Delta, Diana, Flower Dragon, Formosa, Lantha, MK-W559, Promise, Redlicious, Southern Crimson, Sugar Baby, Sweet Black, Sweet Favorite, Vanguard, Verona, Vista
  • Yellow flesh: Ace Phoenix, Tiny Orchid, Yellow Baby
• Muskmelons
  • Aphrodite, Athena, Burpee Hybrid, Dove, Earliqueen, Fastbreak, Halona, Jaipur, Maverick, Minerva, Odyssey, Orange Sherbert, Pulsar, Strike, Sweet 'n Early, Superstar, Venice, Vienna
• Honeydew and Crenshaw melons
  • Passport, Superstar

Melons should have about 2.5cm of water per week.  In hot weather watch leaves for wilting and apply water as needed.

Apply soluble 20-20-20 fertilizer every week prior to fruit set. Increase fertilizing to twice a week after fruit set.

Pick weeds as they appear.

To conserve soil moisture and reduce weeding, apply a thick layer of mulch around your plants, whether in the garden or in a container. Ensure the mulch is not resting against the stems of the plants.

Install a trellis or other support to grow melons vertically. This saves space and improves air circulation which can prevent or reduce problems such as powdery mildew. For heavier fruit, use slings made of nylon pantyhose or other soft cloth. 

Melons benefit from growing in plastic mulches, supported plastic tunnels or crop covers.  Crop covers and tunnels must be removed as soon as flowers appear so that bees and other pollinators can pollinate flowers.

Melons have both male and female flowers on their vines.  Male flowers are the first flowers to appear on the plant.  It is normal for some of these initial male flowers to fall off – don't be alarmed.  Female flowers appear 7-10 days after the male flowers start to appear.  The female flowers are identified by what looks like a small fruit where the stem meets the flower.  This ‘small fruit’ is missing on the male flowers.

Melons are not suited to fall seeding.

Melons are best grown as transplants in the far north. Choose cultivars that mature in less than 70 days. Direct seed only if the soil is very warm. To pre-warm soil, cover soil with a layer of clear plastic 2 weeks before planting. Secure the edges to keep the plastic from blowing away. Remove the plastic after planting.

Melons can be grown in very large containers. Black or dark coloured containers help keep the soil and root system warm.

Melons benefit from black plastic mulch, row covers and clear low plastic tunnels to keep the environment around the plants warm. 

See our preservation section for more videos.

Select a bush type melon for containers.

Melon seeds can be saved from “heritage” or “open-pollinated” plants. If the plant tag or seed package from the original plant says “hybrid”, the plants grown from seeds collected from hybrid plants won't look the same next year.

Melons may sometimes cross with other types of melons, so expect the unexpected. 

To save seeds is to simply wash the seeds to remove as much pulp as possible. Strain the seeds in a colander and spread them on a plate or tray to dry. 
 
How to store seeds
Vegetable seeds can keep for several years if you store them properly. Seeds should be stored in a cool, dry, dark place. Moisture, heat and light can cause seeds to sprout or rot.

• Place your seeds in envelopes or make your own envelopes out of foil or waxed paper. Label with name of the seeds and the date (month and year) you harvested them.
• Place your envelopes inside an airtight container. To help keep seeds dry, place about a tablespoon of dry powdered milk in a paper towel or piece of cloth, secured with a twist tie or piece of string. The powdered milk will absorb humidity and keep seeds dry inside the airtight container.
• Put the container in the refrigerator. Do not store seeds in an unheated shed or garage. These places are either too moist and/or too cold for seed storage.

Cantaloupe and muskmelon are ready to harvest when the fruit skin looks slightly orange in color and the stem end of the fruit easily slips free from the vine. Immature cantaloupe has smooth skin and will get rougher and develop ribbing with maturity.

Watermelon ripeness is harder to determine. The fruit produces a hollow thump when tapped. Look for a dry tendril growing closest to the fruit. The fruit surface starts to dull and loses its shine and it's harder to puncture the rind with a thumbnail. It does not slip or fall off the vine like a cantaloupe. 
 

Coming soon!

• Download entire series here

Common problems include powdery mildew and pollination problems.

Managing cucurbit disease - Michigan State University