By: Mary H. Dyer, Credentialed Garden Writer
Charleston Gray watermelons are huge, elongated melons, named for their greenish gray rind. The bright red fresh of this heirloom melon is sweet and juicy. Growing heirloom watermelons like Charleston Gray isn’t difficult if you can provide plenty of sunlight and warmth. Let’s learn how.
According to Cambridge University Press, Charleston Gray watermelon plants were developed in 1954 by C.F. Andrus of the United States Department of Agriculture. Charleston Gray and several other cultivars were developed as part of a breeding program devised to create disease-resistant melons.
Charleston Gray watermelon plants were widely grown by commercial growers for four decades and remain popular among home gardeners.
Here are some helpful tips on Charleston Gray watermelon care in the garden:
Plant Charleston Gray watermelons directly in the garden in early summer, when the weather is consistently warm and soil temperatures have reached 70 to 90 degrees F. (21-32 C.). Alternatively, start seeds indoors three to four weeks before the last expected frost. Harden the seedlings for a week before transplanting them outdoors.
Watermelons require full sunlight and rich, well-drained soil. Dig a generous amount of compost or well-rotted manure into the soil before planting. Plant two or three melon seeds ½ inch (13 mm.) deep in mounds. Space the mounds 4 to 6 feet (1-1.5 m.) apart.
Thin the seedlings to one healthy plant per mound when the seedlings are about 2 inches (5 cm.) tall. Mulch the soil around the plants when the seedlings are about 4 inches (10 cm.) tall. A couple inches (5 cm.) of mulch will discourage weeds while keeping the soil moist and warm.
Keep the soil consistently moist (but not soggy) until the melons are about the size of a tennis ball. Thereafter, water only when the soil is dry. Water with a soaker hose or drip irrigation system. Avoid overhead watering, if possible. Stop watering about a week before harvest, watering only if the plants appear wilted. (Keep in mind that wilting is normal on hot days.)
Control growth of weeds, otherwise, they will rob the plants of moisture and nutrients. Watch for pests, including aphids and cucumber beetles.
Harvest Charleston Gray melons when the rinds turn a dull shade of green and the part of the melon touching the soil, previously straw yellow to greenish white, turns creamy yellow. Cut melons from the vine with a sharp knife. Leave about an inch (2.5 cm.) of stem attached, unless you plan to use the melon immediately.
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Read more about Watermelons
Binomial Name: Citrullus lanatus
Watermelon Varieties: Black Diamond, Jubilee, Sugar Baby
Sugar Baby is an early season watermelon, coming to maturity approximately 75 days after germination. The small size of the fruits, and relatively short time to harvest, make Sugar Baby on of the easier varieties to cultivate. Sugar Baby melons typically do not exceed 10 pounds, with flavor red flesh and a light green rind with dark stripes.
As they require a long growing season, watermelons are best started indoors approximately 3-4 weeks prior to the last frost of the season. Sow seeds 1/4" deep in flats or small pots, sowing 3 seeds per pot. Keep medium moist while awaiting germination. Additionally, watermelon seeds will show better germination rates with heat. Keep the soil between 80-90 degrees, using a heat mat if necessary. Seed should begin to germinate within 3-10 days.
Once seeds start to germinate, lower soil temp slightly to the mid 70s, for 1-2 weeks, also decreasing water. Thin to one plant per cell or pot. Once the first set of true leaves has developed, reduce waterings once more, but do not allow plant to become desiccated.
Harden plant by gradually exposing to outdoor conditions. Transplant to permanent site in late spring after the last frost has passed. If possible, transplant on an overcast day to minimize wilting and create a more amenable environment for your young plant.
If you have long, hot growing seasons, melons can direct-seed into garden. To ensure ripening in areas with shorter growing seasons and cooler weather, choose fast-maturing varieties, start plants inside, use black or IRT plastic mulch to warm soil and use fabric row covers to protect plants.
Direct-seed 1 to 2 weeks after average last frost when soil is 70 F or warmer. Plant 1 inch deep, 6 seeds per hill, hills 4 to 6 feet apart or 1 foot apart in rows 5 feet apart. Can plant at closer spacings if trellised. Thin to 2 to 3 plants per hill.
Choosing a Site
Prefers warm, well-drained, soil, high in organic matter with pH 6.5 to 7.5. Consistent, plentiful moisture needed until fruit is about the size of a tennis ball. Soil temperatures below 50 F slow growth. Consider using black plastic and fabric row covers to speed soil warming. Sandy or light-textured soils that warm quickly in spring are best.
In many areas, successful crops require starting plants indoors, using plastic mulch to warm soil, and fabric row covers to protect young transplants.
For transplanting, sow seeds indoors ¼ inch deep in peat pots (2-inch square or bigger), 2 to 4 weeks before setting out. Plants should have one or two true leaves when transplanted.
Transplant at same spacings as direct-seeded crops - 2 to 3 plants per hill in hills spaced 4 to 6 feet apart, or 1 to 2 feet apart in rows 5 feet apart. Transplants are delicate and roots are sensitive to disturbance. If you need to thin, use scissors. Keep soil intact around plant when transplanting.
Mulch plants after soil has warmed to help maintain consistent moisture and suppress weeds.
If using fabric row covers, remove at flowering to allow pollination by bees. Good pollination is critical to fruit set.
Plants require consistent moisture until pollination. Once fruits are about the size of a tennis ball, only water if soil is dry and leaves show signs of wilting.
To prevent insect damage to developing fruits, place melons on pots or pieces of wood.
If growing melons on a trellis, support fruit with slings made from netting, fabric, or pantyhose. Trellising improves air circulation around plants and can help reduce foliar disease problems. Choose small-fruited varieties and reduce plant spacing.
For large plantings, leave a strip of rye cover crop every second or third row perpendicular to prevailing winds to protect plants from damaging wind.
To reduce insect and disease problems, avoid planting cucumber family crops (melons, squash, pumpkins) in the same spot two years in a row.
Do not let your melon plants get dried out during the growing season. They are not tolerant of drought. Additionally, be cautious not to over-water plants as this can negatively impact the taste and flavor later on. Keep soil moist but not soggy.
Harveting watermelons is not as straight forward as many other vegetables when it comes to deciding exactly when to harvest. One of the reasons is that they do not slip off the vine like cantaloupes when ripe. This makes it is necessary to look for other indicators. Rolling the melon over and looking at the ground spot where the melon was laying is probably the best method. If that portion of the watermelon is a pale yellow color, the melon should be ripe. You can also look at the tendrils (short, curly, stem-like vine) next to the melon. The tendrils are close to the area where a leaf is attached to the main vine. When the first tendril next to the fruit looks dead and dried up, the melon closest to that tendril should be ripe. Watermelons will store longer than other melons and should be refrigerated, especially after cut.
Scoop out the seeds from a ripe melon and put them into a wire mesh sieve, then with running water over the seeds rub them gently against the mesh, using it to loosen and remove the stringy fibers. Next place the cleaned seeds in a bowl of water, stir it a few times. Some seeds will float to the top. these are immature or sterile melon seeds, they are hollow and/or light-weight and will float to the top of the water. Skim away these bad seeds and discard them. Stir a few more times and repeat the process until no more sterile seeds float to the the top. Drain the water from the remaining seeds.
Afterwards, line a heavy plate or baking pan with waxed paper, spread the seeds out in a single layer onto the waxed paper and place it in sunny spot to air-dry.
Stir the seeds occasionally during the next few hours to make sure all sides are exposed to fresh air, this facilitates even drying. After a day in the sun bring the seeds into the house where they continue to dry for another week or two, stir them daily so they dry evenly. If you've got rainy weather the increased humidity can prolong the drying process another week or so.
Melons have thick seeds so be sure they are thoroughly dry before packing them for storage.
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Heirloom Charleston Grey Watermelon Seeds:
The Charleston Grey (Or Charleston Gray) is a classic heirloom watermelon that dates back to the 1950's. The flesh is pink, firm, and sweet – absolutely delicious! An excellent choice for the home gardener or market grower.
Watermelons grow best in warm weather and sandy soils. Make sure their trailing vines have plenty of space and let your melons enjoy the warm summer sun for delicious, sweet harvests!
|Name:||Watermelon Seeds - Charleston Grey|
|Botanical Name:||Citrullus lanatus|
|Light Requirement:||Full Sun|
|Planting Season:||Warm Season|
|Plant Type:||Long vine|
|Fruit Size:||25+ lbs|
|Days to Maturity:||60-90 Days|
|Plant Spacing:||36-48 inches|
|Planting Depth:||1 inch|
|Sowing Method:||Start Indoors, Direct Sow|
|Hardiness Zones:||3, 4, 5, 6, 7, 8, 9, 10|
When to plant:
If you live in a climate with a short growing season, consider starting your watermelon seeds indoors 4 to 6 weeks before transplanting seedlings into the garden. Sow watermelon seed directly, or set out your transplants 3 to 4 weeks after the last average frost date in spring. Watermelon demands warm temperatures – both soil and air. Transplant or direct sow watermelon seeds only when the average soil and daytime air temps are at least 70F. Watermelons are heavy feeders and need soil rich in nutrients. They grow best in loose, well-drained, but moisture-retentive soil rich in organic matter. Amend your soil with aged manure, seaweed, and/or compost before planting.
How to plant:
Dig a hole 12” deep and 24” wide, fill with compost, manure and several handfuls of sand – this will create an area that is both moisture retentive and well-draining. Use the soil that was removed from the hole to create the mound and then sow your seed or transplant there.
Sow Watermelon seeds 1” deep, planting 4-6 seeds (or transplanting 2-3 of your strongest seedlings) in mounds that stretch 24” across. Planting on hills or mounds ensures that roots stay warm and the soil is well-drained. If direct sowing, wait until your young seedlings have developed three to four true leaves and choose to keep your strongest 2-3 plants by cutting the thinned out seedlings at soil level with scissors. If you pull out your weakest seedlings, you may disturb the tender roots of your remaining plants, so use of scissors or clippers is advised. Build mounds 5-10 feet apart.
We advise using a nitrogen fertilizer on your watermelon plants until flowers form. Then, switch to a high phosphorus and potassium fertilizer like liquid seaweed. Keep area well weeded, we don’t want our watermelons fighting for nutrients and water. Because this is a warm-season crop, it is helpful to mulch around the base – this will help with weed control and moisture retention.
Watermelons are 95% water and require plentiful, even watering for quick growing. Keep the soil moist until fruit reaches full size then stop watering while the fruit ripens.
When to harvest:
Stop watering your watermelons about 10-14 days before the fruits are ready to harvest, this will concentrate the plant’s sugars and your watermelon will be sweeter. You may want to place a board under each melon to keep the fruit clean and dry. Watermelons will be ready to harvest after 70-90 days from sowing. Most people tap their watermelons and listen for a dull thump to know when the fruit is ripe. Other maturation signs include the ceasing of growth, the yellowing of the underside and the drying of the stem near the fruit’s base.
Other tips (if any): Companion plants are corn, radish, beans, nasturtiums, marigolds and oregano. Bad companions are potatoes as they attract many of the same insects that feed on watermelon plants.
Avoid growing watermelon where night temperatures dip below 50 F this will cause fruit to lose flavor. If temperatures exceed 90F for several days, flowers will drop without setting fruit. Watermelons require 70-90 frost-free days to reach harvest and will tolerate no frost. In cool or short-season regions, plan ahead by starting indoors or choose smaller varieties that come to harvest early.
Watermelon leaves commonly wilt in the afternoon sun, this is ok. If you see the leaves wilting before noon, immediately water as it is a sign of stress due to the heat and drought. Never allow the vine itself to become dry. A soaker hose or drip irrigation is the best way to water.
If you live in an area where the weather and soil are dry, try planting your watermelon in inverted hills rather than mounds. Make an inverted hill by removing two inches of soil from a circle 24” across, and use this soil to make a rim around the circle. This way, irrigation water or rainfall can be captured. We know lots of gardeners in Zones 9 and above use this technique for their watermelon, squash, beans, and many other summer vegetables.
Regular, even watering will help fruits avoid blossom-end rot which is caused by fluctuation of soil moisture.