How to Plant, Grow, and Care for ‘Sugar Baby’ Watermelons

Growing full-sized watermelons can seem daunting for home gardeners. They take up a lot of space and produce a massive fruit. If that’s not your style, try the “icebox” variety ‘Sugar Baby,’ packed with the same nutrients, juiciness, and flavor as their giant counterparts. Join organic farmer Jenna Rich as she discusses how to plant, grow, and care for it.

Written by Jenna Rich Last updated: August 21, 2024 | 9 min read

A Citrullus lanatus growing in a greenhouse, surrounded by lush green foliage.

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I hadn’t grown watermelons until this season, and ‘Sugar Baby’ happened to be the one I ended up with. A neighbor had saved seeds from a previous year and asked me to start some for her in my greenhouse. I was happy to oblige and even happier when she offered me any extras as she only wanted four plants.

Once summer was in full gear, I transplanted two seedlings into their own fabric grow bag and set them alongside my Birdies metal raised beds. Before long, their vines intertwined with my tomatoes, peppers, and cucumbers. It was a beautiful jungle of all my favorite summer crops, and the melons performed well in their bags. After noting signs of full maturity, I harvested the first of several, and let me tell you, they did not disappoint.

I recommend this delicious heirloom variety if you have space for a mini watermelon. Let’s learn how to plant, grow, care for, and enjoy ‘Sugar Baby’ watermelons.

Sugar Baby Watermelon Seeds

Personal sized
Delectably sweet
Abundant production
80 days to mature

View at Epic Gardening Shop

‘Sugar Baby’ Watermelon Overview

A large, sliced Citrullus lanatus with a few whole fruits on a wooden surface.


Botanical Name Citrullus lanatus Plant Type Heirloom icebox watermelon Family Cucurbitaceae Genus Citrullus Special Characteristics Exceptionally sweet, quick to mature	Native Area Africa Sun Exposure Full sun Height 15 to 24 inches Watering Requirements Moderate Soil Type Loamy, well-draining, slightly acidic	Pests Flea beetles, aphids, cabbage loopers, cutworms Diseases Downy and powdery mildew, anthracnose, fusarium wilt, damping off, bacterial fruit blotch, cercopsora leaf spot, angular leaf spot, and verticillium wilt Maintenance Low to moderate Hardiness Zones USDA Zones 2 to 11, best in 9 and 10 Days to Maturity 75 to 85

What Are ‘Sugar Baby’ Watermelons?

A Citrullus lanatus growing in a planter under the bright Arizona sun. — While mostly water, this heirloom also contains antioxidants, potassium, Vitamin C, carotenoids, and lycopene.

This variety is an easy-to-grow, juicy, compact watermelon, an excellent option for individuals or young families. While mostly water, this heirloom also contains antioxidants, potassium, Vitamin C, carotenoids, and lycopene. It’s prolific, and our community loves it for its high yields, delicious flavor, consistency, and overall good health. ‘Sugar Baby’’s high sugar content gives it its standout sweetness.

Appearance

A ripening Citrullus lanatus nestled among healthy garden leaves. — Each fruit weighs eight to ten pounds and is seven to ten inches in diameter.

This adorable melon is small, round, deep green externally, with gorgeous dark red internal flesh. There may be some faint lighter green striping on the outside. The seeds are roundish and medium brown, and the rind is minimal. Each fruit weighs eight to ten pounds and is seven to ten inches in diameter, and each plant produces two to five melons.

Native Area

Close-up of a Citrullus lanatus fruit surrounded by green leaves and soil. — It quickly gained popularity for its size, flavor, and heirloom status.

‘Sugar Baby’ watermelons are native to Africa and was introduced to the United States in the 1950s. It quickly gained popularity for its size, flavor, and heirloom status.

How to Grow

These are sensitive to transplant, but with extra care, they’ll succeed without issues. ‘Sugar Baby’ watermelons are known for being low-maintenance.

Sunlight

A Citrullus lanatus growing in a garden in the Moscow region, surrounded by dense foliage. — Sunlight promotes ample flower production and stimulates pollination.

Place plants where they’ll receive eight to ten hours of direct sunlight daily. Sunlight promotes ample flower production and stimulates pollination, and full sun will ensure their flesh is super sweet.

Water

Citrullus lanatus plants flourishing in a field, ready for harvest. — Water at the base to ensure it reaches the roots.

Watermelons are named as such because they contain high water levels and require a lot of water to produce their massive, sweet, and juicy fruits. Water them one to two inches weekly if they have not received that much rainfall.

Water at the base to ensure it reaches the roots. The soil should be consistently moist but not soggy.

Soil

Small yellow flowers beginning to bear fruit on a Citrullus lanatus plant. — A soil test before planting will help determine if you need to acidify your soil.

Watermelons thrive in rich, loamy soil high in organic matter, which should remain moist throughout the growing season.

The pH is ideally between 6.0 and 6.8, but they will tolerate anywhere between 5.0 and 7.0. A soil test before planting will help determine if you need to acidify your soil.

Mulch

Short-season growers in northern regions may add heavy straw mulching or silage tarps (black side up) around their melons and pathways to warm the soil temperatures. Mulching adds the bonus of suppressing weeds and fertility to the soil as it breaks down.

Climate and Temperature

A ripe Citrullus lanatus fruit resting on the soil, ready for harvest. — If the spring is unseasonably cool, start seeds later to avoid rootbound seedlings.

Watermelons prefer air temperatures between 70 and 85°F (21 and 29°C). Cooler temperatures may stunt their growth and cause mushiness, and they will not tolerate a frost. Cover new transplants with a row cover to protect them from spring temperatures.

Cool spring soil temperatures are not great for watermelon production. If the spring is unseasonably cool, start indoor seeds later to avoid rootbound seedlings.

Fertilizing

Hands spraying Citrullus lanatus plants with a protective solution. — Give a nitrogen boost before flowering occurs, around the time tendrils appear and vines lengthen.

‘Sugar Baby’ watermelons are heavy feeders, requiring high amounts of nutrients, water, and composted organic matter. A weekly fish emulsion foliar feed helps them thrive. You may side-dress with compost halfway through the season.

Give a nitrogen boost before flowering occurs, when tendrils appear and vines lengthen. Switch to fertilizers that are heavier in potassium when you remove the insect netting, and flowering begins.

Harvesting

An array of Citrullus lanatus fruits, filling the frame with their deep green skins. — There may also be a light green or yellow spot on the exterior where it sits on the soil surface.

Around 75 to 80 days after transplant, begin monitoring for shriveled curly-Qs near the melon as it’s one of the tell-tale signs that it’s ready for harvest. At this time, the fruit is receiving no additional nutrients from the plant. There may also be a light green or yellow spot on the exterior where it sits on the soil surface and is tough to the touch.

Gently tug on the fruit. If it releases itself without much effort, this confirms your suspicion, but if it fights back, leave it for another day or two.

Pruning

An organic Citrullus lanatus growing in a home garden, surrounded by other vegetation. — When the season is nearing its end and cooler nights have arrived, some growers snip the growing tip.

When thinned to the proper spacing, no pruning is necessary. However, when the season is nearing its end and cooler nights have arrived, some growers snip the growing tip so the plant can focus its energy on ripening the fruit on the vine.

Propagation

Young Citrullus lanatus sprouts emerging from the soil, ready to be transplanted. — They can be directly sown or started indoors.

‘Sugar Baby’ watermelons can be directly sown or started indoors three to four weeks before the last frost.

Start Seeds Indoors

Citrullus lanatus seedlings with seed coats still attached, beginning to germinate. — Provide seedlings with eight to ten hours of sunlight immediately after germination.

In areas with short growing seasons, sow seeds about a ½ inch deep in cell trays with premium, well-draining seed starting mix. Add these heat lovers to a heat mat set between 75 and 85°F (24 and 29°C), ensuring the soil doesn’t dry out. Seeds should germinate in five to ten days.

Provide seedlings with eight to ten hours of sunlight immediately after germination. When temperatures allow, harden them off for up to a week before transplanting. Protect them from harsh winds and bring them indoors if overnight temperatures drop below 60°F (16°C). They will not tolerate a frost.

Direct Sow Outdoors

A young Citrullus lanatus seedling planted in a garden, freshly watered with the soil still wet. — Thin to your desired spacing once you see where germination has taken place.

Oversow seeds to account for critters stealing them and less than 100% germination. Do this one to two weeks after your last frost. Thin to your desired spacing once you see where germination has taken place. Wait until the soil is warm enough for the best results.

Planting

Citrullus lanatus plants spreading across the ground in a well-tended garden. — In colder areas, growers should start them indoors.

Growers in warm regions may choose to sow ‘Sugar Baby’ watermelons directly, while in colder areas, growers should start them indoors.

Spacing

Citrullus lanatus seeds planted in a dry garden bed, ready to sprout. — Thin to at least six foot spacing between rows if you aren’t pruning.

Space plants out at four feet or one per 7 to 10-gallon grow bag. Thin to this spacing if you direct-sowed seeds. Their vines are long and require lots of water and nutrients, so don’t push these space boundaries too far, or you’ll be disappointed. Leave at least six feet between rows if you don’t plan to prune. Experiment with closer spacing and pruning in smaller spaces. These melons are even small enough to trellis with support.

Transplanting

A moist garden bed with young seedlings having delicate, hairy stems and broad, heart-shaped leaves with a vibrant green hue. — Use a trowel or your hand to create a hole a bit deeper than the size of the seedling.

Like other cucurbits, melons don’t love having their roots disturbed, making them a direct sow option for many growers. However, if you have a warm, indoor growing area where you can safely start seeds, you can get a head start on the long season and get this summer treat earlier.

Watermelons love warm weather, so transplant them in warm, moist soil when temperatures reach about 70°F (21°C) well after the risk of frost has passed. Use a trowel or your hand to create a hole a bit deeper than the size of the seedling, gently place it in the hole, and surround it with soil. Tamp down the soil around it and water it immediately.

Add hoops and cover upon transplanting to protect them from flea beetles and other pesky spring pests. Remove the covering when flowering begins.

Common Problems

A Citrullus lanatus plant affected by Fusarium wilt, showing wilted leaves. — Some fungal diseases can cause wilting in young seedlings, but usually occur after fruit set.

You can avoid common pests, diseases, and growing problems when you know what to look for.

Pests

Close-up of a flea beetle, a tiny, shiny beetle with a rounded, metallic-colored black body, on a green toothed leaf. — To minimize damage, cover with a row cover upon transplanting.

The most common pests include:

Flea Beetles

Flea beetles may cause issues in the early part of the season when plants are small and vulnerable. To minimize damage, cover with a row cover upon transplanting.

Aphids

You can organically manage aphids with firm streams of water or neem oil. They may be small, but their damage can be mighty, and populations grow quickly. Planting alyssum, cilantro, yarrow, lavender, fennel, dill, and buckwheat nearby attracts beneficial insects that are predators of aphids.

Cabbage Loopers

Cabbage loopers cause cosmetic damage to young seedlings, but if left alone, they can defoliate entire patches of crops. They become camouflaged against green leaves, so keep your eyes peeled for them. These tiny green worms aren’t fussy about their meals; they get bigger and more destructive each day.

Female looper moths can lay up to 600 eggs in their short, 12-day life. Attracting ladybugs, native birds, lacewings, frogs, and toads will help control these worms. Bt spray is a common treatment for these.

Cutworms

Cutworms hide under the soil surface, waiting for you to put young, vulnerable seedlings out for them to feast on. They come out at night and chew down their necks, leaving you with an awful morning surprise. Once the necks are severed, there’s no saving the plants.

Some growers add collars around the base to deter them or turn over the soil a few days before transplanting, exposing the cutworms to predatory birds. Bt can be used in infestations.

Diseases

Powdery mildew visible on the leaves of a Citrullus lanatus plant. — Look for yellow spots, white mycelium growth, and leaves becoming brown and dry in the daytime.

The most common disease issues include:

Downy Mildew

The oomycete Pseudoperonospora cubensis causes downy mildew (DM). Symptoms on the leaves include yellow or green lesions, fuzzy spots, and deformity. Ideal conditions for this disease occur when daytime temperatures are around 60°F (16°C), and nighttime temperatures are around 70°F (21°C).

It travels quickly in windy and rainy conditions. Control it with fungicides or organic copper spray. Thankfully, studies show it cannot overwinter in areas that receive a killing frost.

Powdery Mildew

Powdery mildew (PM) symptoms appear first on the oldest leaf surfaces. Look for yellow spots, white mycelium growth, and leaves becoming brown and dry in the daytime. PM, caused by Podosphaera xanthii, may lead to smaller fruit, poor-quality plants, and death. You can treat it with fungicides, but should not do so once they flower.

Anthracnose

Anthracnose is affected by Colletotrichum orbiculare, which strikes when it’s warm and humid. You may notice small spots on the leaves resembling those of PM, sunken fruit, and infected stems. To avoid this nasty disease, secure seeds from a reputable source, practice proper crop rotation, and avoid working in the field when wet.

Fusarium Wilt

Fusarium wilt is highly destructive and caused by Fusarium oxysporum f. sp. niveum (F. oxysporum). While the soil-borne fungal disease could cause wilting in young seedlings, it usually occurs after fruit set. It prefers sandy, slightly acidic soil. Take note of any signs of it early on and apply fungicides to control it. Brown or yellow streaking, wilting, and vascular tissue may be present. Remove damaged plants and dispose of them. Rotate your crops to prevent the proliferation of wilt.

Damping Off

Damping off is caused by various fungal pathogens, but the most common include the Pythium species and Rhizoctonia solani. They commonly affect young transplants when conditions are cool, damp, and indoors under glass. To avoid this, ensure proper ventilation and warmth, and always clean your tools and seed-starting supplies after each use to stop the spread.

Gummy Stem Blight

The fungus Didymella bryoniae causes gummy stem blight (GSB) in cucurbits. It causes oozing stems, leaf spots that eventually cause them to drop off, and small black spots on petioles. Treat with fungicides and remove the infected plant immediately.

While these are just a few pests and diseases that may affect your ‘Sugar Baby’ plants, they are the most common. Other diseases include bacterial fruit blotch, cercopsora leaf spot, angular leaf spot, and verticillium wilt.

Overcrowding

A small Citrullus lanatus growing on a farm, surrounded by healthy green leaves. — Plants cannot produce high-quality fruits if forced to compete for water and nutrients.

While ‘Sugar Baby’ is a mini watermelon variety, it is still a vining crop that requires space. Plants cannot produce high-quality fruits if forced to compete for water and nutrients.

Weed Competition

A gardener pulling weeds with a hoe in a Citrullus lanatus plantation. — Weed your patch weekly by hand or a hoe while the plants grow.

As mentioned, mulching and silage tarps will help suppress weeds. If you prefer not to cover the soil surface, weed your patch weekly by hand or a hoe while the plants grow. Eventually, the vines will cover the soil and keep weed pressure down.

Harvesting Too Early

A ripe Citrullus lanatus with a yellow field spot, indicating maturity. — If you harvest them too early, the flavor will be less sweet and juicy.

Remember the key four characteristics to look for in a ripe watermelon.

Brown and shriveled curly-q near the fruit
Yellow or light green spot on the bottom of the fruit
Hollow sound when you gently knock
It easily pulls off the vine when you tug on it

If you harvest them too early, the flavor will be less intense and delicious, and the internal flesh may be less red or juicy.

Frequently Asked Questions

As vining creepers, watermelons make good ground covers that keep weeds down and are good companions for basil, beans, cabbage, and lettuce. But they can also choke out neighbors if you’re not careful, and they won’t pair well with plants that prefer dry soil, as they need lots of water to produce a whole, juicy fruit.

This heirloom produces a perfectly sweet and juicy personal-sized watermelon in 75 to 80 days, rather than the 120 days a full-size watermelon takes to mature.

Yes, it performs well in a fabric grow bag or pot with well-draining soil placed in full sun. Provide plenty of compost and nutrients, as melons are heavy feeders.

Fresh is definitely best, but you can toss them into smoothies, freeze them for a hot summer day treat, and even grill them on spears for a unique BBQ experience.