Citrullus

( sit - ruh - luss )

At-A-Glance Information

This genus of desert vines is native to desert regions of Africa, and was first introduced to North America when enslaved Africans brought seeds with them. They quickly became one of the most popular summertime fruits, and are now cultivated world wide. They can be grown in many different situations, as long as they get full sun and have well-draining soil. Grow these popular, sweet fruits in raised beds, containers, or simply in the ground as members of edible gardens.

Citrullus Species and Varietals

The genus Citrullus is a member of the plant family Cucurbitaceae, and includes seven species. The best growing zones for Citrullus plants vary depending on the species grown. For more information, see the species descriptions below. To find your zone, click here: Zone Map.

Citrullus amarus (Citron, Fodder Melon, Preserving Melon, Red-Seeded Citron, Jam Melon, Stock Melon, Kalahari Melon, Tsamma Melon, Pine Melon)
This species is native to Africa, where it is cultivated in dry or desert areas. It is considered an invasive, weedy species in Mexico and some other areas of the globe. Fruits resemble Watermelons, but are smaller and more rounded. The meat is white and dense, and has a strong flavor. It is not considered palatable when raw, and is commonly cooked or processed. This species is considered invasive in western Mexico.

Citrullus ecirrhosus (Namib Tsamma, Tsamma Melon)
This species of perennial desert vines is native to Namibia and South Africa, and produces white, bitter flesh. Vines can reach up to over six feet long, and are hardy, surviving with little water and strong sunlight. Leaves form annual stems that die back each year.

Citrullus lanatus (Watermelon, Desert Watermelon)
This annual species forms a scrambling, trailing vine and is widely cultivated around the world for its sweet fruits (botanically called a pepo). Pepos are large, up to 24 inches in diameter (8 inches in wild sub-species), and have green, striped rinds and red flesh (though flesh can also be pink, orange, yellow, or white). There are hundreds of different varieties in assorted shapes, sizes, and colors. This species is considered invasive in Australia and Florida, United States.

'Ali Baba'
Oblong fruits with red flesh to 12-30 lbs. 80-85 DTM.

'Black Diamond'
A classic cultivar with thick rind and red flesh. Great variety for rind pickles. 40-45 lbs. 90 DTM.

'Blacktail Mountain'
With red flesh and a dark green rind. To 6-12 lbs. 70-75 DTM.

'Carolina Cross'
This cultivar produced the record-winner for heaviest watermelon, and produces red-fleshed fruits between 65 and 150 lbs. 100 DTM.

'Cream of Saskatchewan'
This variety produces small, round fruits up to 10 inches in diameter. Rind is thin, and flesh is white. Grows well in cool climates. 85 DTM.

'Densuke'
With rounded fruits up to 24 pounds; rind is black and unstriped, and flesh. Very valuable fruits. 85-90 DTM.

'Faerie'
Red flesh and a yellow rind. Small fruits to 5-6 lbs. 70-75 DTM.

'Georgia Rattlesnake'
An old-school cultivar with great flavor and a thick rind. 90 DTM.

'Golden Crown'
Red flesh and yellow rind fruits to 4-7 lbs. 70-75 DTM.

'Golden Midget'
This variety has a golden rind and pink flesh. 70-80 DTM.

'Melitopolski'
Produces small, rounded fruits up to a foot in diameter. Great for cool-weather areas. 95 DTM.

'Moon and Stars'
Created in 1926, this variety has a purple-black rind and produces 20-50 lb. fruits. Flesh is pink-red. 80-85 DTM.

'New Queen'
Orange-fleshed melon with few seeds and high sugar content. 80-85 DTM. Up to 5-6 lbs.

'Orangeglo'
With very sweet orange flesh and an oblong shape. Light green rind. 90-100 DTM.

'Revolution'
Melon with red flesh, mature in 80 days. 20-26 lbs. Seedless variety.

'Sugar Baby'
Red-fleshed cultivar to 6-10 lbs. 70-75 DTM.

'Super Seedless'
Red-fleshed and seedless, 90-95 DTM.

'Sweet Bite'
Red fleshed, seedless fruits up to 5-8 lbs. 75 DTM.

'Tom Watson'
An older commercial cultivar with a thick rind and red flesh. 90 DTM.

'Triple Gold'
Yellow flesh in fruits up to 8-10 lbs. 75 DTM. Seedless.

Caring for Citrullus

Citron plants are typically grown from seed, either started indoors and transplanted or direct-sown into the garden. Most cultivars take between 80 and 90 days to mature, though there are some short-season varieties available that can be harvested after just 70 days. Make sure that your garden is prepared for these plants ahead of time; they have a widely sprawling habit and will climb over and through other plants in the landscape. They appreciate a space in the garden that receives full sun; ideally, they like to get between 6 and 8 hours of direct sun each day. Ensure that soil is very well-draining (these plants are naturally desert-dwellers and grow in sandy soils), moderately fertile, and has a pH of between 6.0 and 6.8 (slightly acidic to neutral). Watermelons, the most popular Citron, are typically planted in slightly mounded hills spaced between 4 and 6 feet apart. Two or three plants are cultivated per hill. If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention.

Water new plantings regularly as they establish a strong root system in their new home. At maturity, these plants can withstand short periods of drought. When fruits are set and about ready to be harvested, lessen waterings to increase sweetness. Watermelon plants are heavy feeders. Fertilize the planting area with compost a few times during the growing season from spring through the end of summer to provide them with enough organic material to grow and produce well. To fertilize, pull mulch back before applying 2 inches of compost, work the compost gently into the soil a bit, water it in, and then replace mulch. These plants do not need pruning, but to clean up the look of vines, any dead, damaged, or diseased foliage can be removed at any time during the growing season. After harvesting, the rest of the plant can be pulled from the ground and composted.

Harvesting Watermelon
Watermelon plants need to be pollinated to produce fruits; keep in mind when planting that seedless plants should be interplanted with seeded watermelons to allow for pollination to occur. Generally, between 2 and 4 watermelons are produced per vine. As fruits become larger and larger over time, set a piece of cardboard or a layer of straw bedding underneath to protect them from rot and pests. Watermelons are considered ripe and ready to harvest when the rind becomes dull in color, the curly tendrils on the vine near melons turn brown and dry out, and the part of the fruit that rests on the ground will begin to change from pale light green to pale light yellow. Fruits are best when eaten right away, and are fantastic when fresh. Cut watermelon can be refrigerated for a few days, but does not last long. Don't store uncut melons in the refrigerator; instead, opt for a cool (between 45 and 50 degrees Fahrenheit), dark space. They will keep for about two weeks in this storage situation.

Disclaimer: Information contained on this website is strictly and categorically intended as a reference to be used in conjunction with experts in your area. Foraging and consumption of plant parts should never begin without the guidance and approval of a local plant specialist. The providers of this website accept no liability for the use or misuse of information contained in this website.

Propagation

Citrullus, or Citron (Watermelon), can be propagated through cutting or seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant, especially if you are propagating a hybrid cultivar. To propagate your Citron plant, follow the instructions below:

Propagating Citrullus by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. The seed heads on plants are pretty easy to spot, they're left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will continue to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Get your container prepared. Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 2-6 weeks from sowing.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 65 and 72 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Citrullus by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 3-4 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new plant.

Citrullus fruits contain seeds.

Watermelon seeds.

Problems and Pests

These vines can be considered invasive in some areas of the world, including Australia, Mexico, and the southeastern United States. Check with local authorities before planting. Citrullus, or Citron, plants are typically pest and disease free, however they can have issues with the following from time to time if growing conditions are not met: