Watermelon Farming
Watermelon (Citrullus lanatus) is a popular fruit crop grown for its juicy, sweet flesh. It is a warm-season crop that requires careful management to achieve high yields and quality. Watermelon farming profit per acre can be significant with proper planning and execution. Watermelon cultivation involves a total investment cost of NRs. 196,000 per acre, with an estimated total income of NRs. 320,000 from a yield of 16,000 kg sold at NRs. 20/kg.
The net profit is calculated as NRs. 124,000 (Total Income – Total Cost), indicating a profitable venture under the given assumptions. To break even, a minimum yield of 9,800 kg is required to cover the total cost of NRs. 196,000. Proper management and optimal growing conditions can further enhance watermelon farming profit per acre, making it a lucrative option for farmers. Below is a detailed guide on watermelon farming practices:
Land Preparation
Clearing the field of weeds, rocks, and trash is the first step in preparing the land for watermelon production. Next, deep plowing (20–30 cm) is done to increase aeration and loosen the soil. Harrowing is the process of leveling the field with a harrow to produce a fine tilth. Lastly, elevated beds or ridges are created to improve drainage and avoid waterlogging. The beds are placed 1.5–2 meters apart to guarantee the best possible crop growing conditions. Two crosswise ploughs are used to fine-till the land, guaranteeing that the soil is ready for sowing.
Soil Type
Sandy loam or loamy soils are ideal for watermelon growth because of their high organic matter content, adequate drainage, and ability to hold onto moisture. Their ideal pH range for nutrient uptake is 6.0–7.0, which is slightly acidic to neutral. Because they hold too much water, heavy clay soils are inappropriate and can lead to root rot and poor aeration. Successful farming depends on choosing soils that drain effectively or enriching them with organic matter.
Climatic Requirements
Watermelons require warm temperatures, ideally between 25°C and 35°C, as they are sensitive to frost and cold conditions, making them unsuitable for cooler climates. Moderate rainfall of 600-1000 mm is suitable for their growth, but excessive rain can lead to waterlogging and increase the risk of diseases. Additionally, full sunlight is essential for proper growth and fruit development, ensuring healthy vines and high-quality yields.
Major Cultivars
a). Sugar Baby
A popular watermelon, Sugar Baby is distinguished by its small, spherical fruits, which usually weigh 8–10 pounds (3.5–4.5 kg). Its flesh is deep red, incredibly sweet, and juicy, making it a favorite when eaten fresh. Its early maturity period of 75–80 days makes it perfect for areas with shorter growing seasons, and its dark green, comparatively thin skin adds to its appeal. Sugar Baby is prized for its petite size and mouthwatering flavor, making it ideal for small gardens, home use, and farmers’ markets.
b). Crimson Sweet
Crimson Sweet is a widely cultivated watermelon variety known for its oval-shaped fruits that weigh between 20-25 pounds (9-11 kg), featuring bright red, crisp flesh with a high sugar content that makes it exceptionally sweet and refreshing. The light green rind with dark green stripes gives it an attractive appearance, while its maturity period of 85-90 days ensures high yields and disease resistance. Ideal for commercial farming, fresh markets, and processing, Crimson Sweet is prized for its large size and excellent flavor.
c). Charleston Gray
Charleston Gray is a classic watermelon known for its large, oblong fruits that can weigh up to 30-40 pounds (14-18 kg), featuring red, firm, and sweet flesh with a slightly coarse texture. The light green, thick rind makes it resistant to cracking and highly suitable for long-distance transportation. With a maturity period of 90-100 days, this variety is highly adaptable to various growing conditions, making it popular for commercial production, storage, and transport due to its durability and large size.
d). Jubilee
Jubilee is a high-yielding watermelon variety known for its long, striped fruits that weigh between 25-30 pounds (11-14 kg), featuring bright red, juicy flesh with an excellent flavor that makes it a favorite for fresh consumption. The light green rind with distinct dark green stripes gives it an attractive appearance, while its maturity period of about 90 days and vigorous vines ensure disease resistance and reliable growth. Suitable for both home gardens and commercial farming, Jubilee is particularly favored for fresh markets and processing due to its high quality and appealing characteristics.
e). Black Diamond
A classic watermelon, Black Diamond is regarded for its huge, dark green fruits that can weigh up to 50 pounds (23 kg) or more. Its flesh is deep red, sweet, and juicy, and it has a rich flavor. Its mature period of 90-95 days guarantees rapid growth and great yields, and its thick, dark green skin makes it resilient to injury during handling and transportation. Black Diamond is prized for its remarkable taste, size, and durability, making it perfect for large-scale farming, storage, and transportation.
Planting
a). Planting Season
Watermelons are planted during the warm season when the risk of frost has passed, with planting in tropical regions possible year-round, while in temperate regions, it is best to plant in spring or early summer.
b). Spacing
The recommended spacing for watermelon plants is 2 meters between rows and 90 centimeters between plants within a row.
c). Pit Preparation
For pit preparation, dig pits measuring 30 cm x 30 cm x 30 cm and mix well-decomposed manure or compost with the soil before filling the pits.
d). Planting Method
For the planting method, seeds are first soaked in lukewarm water for 12 hours, then drained and kept overnight in a wet gunny bag to enhance germination rates. Seeds can be sown directly into the pits or transplanted as seedlings, with 2-3 seeds planted per pit at a depth of 2-3 cm, using approximately 800 grams of seed per acre. After germination, thin the seedlings to one healthy plant per pit.
e). Number of Plants per Acre
The number of watermelon plants per acre typically averages around 2,200, though this can vary depending on the specific spacing used and the cultivar being planted. Factors such as row spacing and plant spacing influence the final plant count, ensuring optimal growth and yield for the crop.
Intercropping
Intercropping watermelons with short-duration crops such as beans, onions, or leafy vegetables can maximize land use and improve overall farm productivity. However, it is essential to carefully select intercrops that do not compete aggressively with watermelons for critical resources like nutrients, water, or sunlight, ensuring that both the main crop and intercrops thrive without negatively impacting each other’s growth and yield.
Irrigation
Drip or furrow irrigation is advised to avoid waterlogging and guarantee effective water management because watermelons need constant hydration, particularly during flowering and fruit development. Watering should be decreased as fruits get older in order to improve taste and keep them from shattering. Fruit cracking can result from inconsistent watering or irrigation following a protracted dry spell, thus it is imperative to wet the area prior to seeding and to continue weekly irrigation at regular intervals. Furthermore, mulching is recommended to hold onto soil moisture and lessen irrigation frequency.
| Growth Stage | Irrigation Frequency | Water Requirement | Key Notes |
| Pre-Planting | Once | Ensure soil is moist but not waterlogged. | Prepare the field by irrigating lightly to create ideal soil conditions for planting. |
| Planting to Germination | Every 2-3 days | Light irrigation to keep the soil moist. | Avoid overwatering to prevent seed rot. Maintain consistent moisture for proper germination. |
| Seedling Stage | Every 4-5 days | Moderate irrigation to support root development. | Ensure seedlings receive adequate water without waterlogging. |
| Vine Development | Every 5-7 days | Increase water supply as the plant grows. | Watermelons require more water during this stage to support vigorous vine growth. |
| Flowering Stage | Every 5-7 days | Consistent and deep irrigation to ensure proper flower formation. | Avoid water stress, as it can lead to flower drop and reduced fruit set. |
| Fruit Setting | Every 5-7 days | Maintain consistent soil moisture to support fruit development. | Water stress during this stage can lead to misshapen or undersized fruits. |
| Fruit Maturation | Reduce to every 7-10 days | Gradually reduce irrigation as fruits near maturity. | Overwatering during this stage can dilute fruit sweetness and cause cracking. |
| Pre-Harvest | Stop 7-10 days before harvest | Minimal to no irrigation. | Stopping irrigation before harvest improves fruit sweetness and shelf life. |
This schedule ensures optimal growth, fruit development, and quality while conserving water resources. Adjustments may be needed based on local conditions and cultivar requirements.
Fertilizer and Manure
Below is the detailed fertilizer schedule per acre for watermelon cultivation.
| Growth Stage | Nutrient Requirement | Recommended Fertilizer & Dose |
| Pre-Planting (Soil Preparation) | Balanced nutrient availability for initial growth | · Apply FYM/Compost: 10 tons per acre · Apply Azospirillum and Phosphobacteria at 800 g/acre, Pseudomonas at 1 kg/acre, along with 20 kg of FYM and 40 kg of neem cake and mix them thoroughly into the soil. |
| Planting (Seeding/Transplanting) | Encourage root development | · Use starter fertilizer: Apply 10 kg N and 20-25 kg P₂O₅ (from DAP or equivalent) in rows or planting holes. |
| Vegetative Growth (2-4 weeks) | Promote vine growth and foliage development | · Apply 10-15 kg N and 10-15 kg K₂O through urea or potassium sulfate. |
| Flowering (4-6 weeks) | Support flowering and fruit setting | · Apply 10-15 kg N and 15-20 kg K₂O. Use fertilizers like urea and Muriate of Potash (MOP). |
| Fruit Development (6-8 weeks) | Enhance fruit size and sweetness | · Apply 5-10 kg N, 10-15 kg P₂O₅, and 20-25 kg K₂O through fertilizers like urea, DAP, and MOP or potassium sulfate. |
| Ripening (8-12 weeks) | Ensure high-quality fruit production | · Avoid excess nitrogen; focus on potassium. Apply 10-15 kg K₂O using potassium-based fertilizers (e.g., potassium sulfate). |
Weed Control
Weed control is a critical aspect of watermelon cultivation, as weed competition can significantly reduce yields, particularly during the early growth stages when young plants are most vulnerable.
To manage weeds effectively, mulching is highly recommended—using either plastic or organic materials like straw or dried leaves. Mulching not only suppresses weed growth but also helps conserve soil moisture, regulate soil temperature, and improve overall soil health.
Additionally, manual weeding can be performed to remove weeds by hand or with tools, ensuring that the watermelon plants are not disturbed. If herbicides are used, they must be applied carefully and selectively to avoid damaging the watermelon plants. Always follow label instructions and choose herbicides that are safe for watermelon crops. Combining these methods ensures a weed-free environment, promoting healthy growth and maximizing yield.
Pest and Disease Management
Common Pests
a) Red Pumpkin Beetle
The watermelon and other cucurbit crops are frequently afflicted by the red pumpkin beetle (Aulacophora foveicollis). These beetles skeletonize vegetation and make holes in it as they feed on leaves, blossoms, and early fruits. Severe infestations can lower yields and limit plant growth. Crop rotation, physical removal, and, if required, the use of chemical pesticides or insecticides based on neem are all part of management.
b) Fruit Fly
Fruit flies (Bactrocera spp.) are a major threat to watermelon crops, particularly during the fruiting stage. Female fruit flies lay eggs under the fruit skin, and the hatched larvae feed on the fruit pulp, causing rotting and making the fruits unmarketable. Control measures include using fruit fly traps, applying bait sprays, and practicing good field hygiene by removing and destroying infested fruits.
c) Sting Bug
Watermelon leaves are the food source for sting bugs (Corythaica spp.), which are sap-sucking insects that cause wilting, yellowing, and decreased plant vigor. Additionally, the honeydew they expel encourages the formation of sooty mold. In order to minimize infestations, management entails routine observation, the application of neem oil or insecticidal soaps, and upholding field hygiene.
d) Aphids
Watermelon leaves and stems are attacked by tiny, sap-sucking aphids (Aphis gossypii), which results in curling, yellowing, and restricted growth. Cucumber mosaic virus is one of the viral infections they spread. Natural predators like ladybugs can be introduced, neem oil or insecticidal soaps can be applied, and chemical insecticides can be used if infestations are severe.
e) Hairy Caterpillar
Hairy caterpillars (Spilosoma spp.) are voracious feeders that consume watermelon leaves, leading to defoliation and reduced photosynthesis. Severe infestations can significantly impact plant health and yield. Management includes manual removal of caterpillars, using biological controls like Bacillus thuringiensis (Bt), and applying chemical insecticides when necessary. Regular field monitoring is essential to detect and control early infestations.
Common Diseases
a) Powdery Mildew
A prevalent disease in watermelon crops is powdery mildew, which is brought on by the fungus Podosphaera xanthii. It causes decreased photosynthesis and plant vigor and manifests as white, powdery patches on leaves, stems, and occasionally fruits. Severe infections can affect yield by causing premature defoliation and leaf yellowing. Using resistant types, making sure there is adequate space for air circulation, and using fungicides like sulfur or potassium bicarbonate are all part of management. The key to managing this illness is early intervention and routine monitoring.
b) Downy Mildew
Downy mildew, caused by Pseudoperonospora cubensis, is a fungal disease that thrives in humid conditions. It manifests as yellow angular spots on the upper leaf surface and a purplish-gray fungal growth on the underside. Infected leaves may wither and die, reducing the plant’s ability to photosynthesize. Control measures include using fungicides like mancozeb or chlorothalonil, improving air circulation, and avoiding overhead irrigation to reduce humidity levels.
c) Anthracnose
The fungus Colletotrichum orbiculare is the cause of anthracnose, which damages fruits, leaves, and stems. Fruit rot and defoliation may result from the symptoms, which include irregular brown spots on leaves and dark, sunken lesions on fruits.
When the weather is warm and humid, the sickness spreads quickly. Crop rotation, the removal of diseased plant waste, and the use of fungicides such as azoxystrobin or copper-based sprays are all part of management. Additionally, resistant types can lessen the chance of infection.
d) Blight
Fungal diseases like as Alternaria or Phytophthora cause blight, which manifests as dark, wet lesions on leaves, stems, and fruits. Plant tissues may wilt and die quickly as a result, particularly in damp and humid environments. Crop rotation, the use of fungicides like metalaxyl or chlorothalonil, and making sure drainage is adequate to prevent waterlogging are other control measures. To stop the spread, infected plant material must be removed and destroyed.
e) Fusarium Wilt
Fusarium wilt is brought on by the fungus that grows in soil. Watermelon plants are susceptible to the destructive fungus Fusarium oxysporum. Because water-conducting tissues are blocked, the plant eventually wilts, turns yellow, and dies. For years, the fungus may continue to grow in the soil. Utilizing resistant cultivars, rotating crops with non-host crops, and fumigating or solarizing the soil to lower fungus populations are all examples of management. Reducing the effects of this disease can also be achieved by avoiding water stress and keeping the soil healthy.
Harvesting
Depending on the variety, watermelons might take anywhere from 70 to 90 days to achieve maturity and be ready for harvest. Key indicators of ripeness include the following: the fruit will make a hollow sound when tapped, the tendril close to the fruit stem will become dry and brown, and the underside of the fruit—where it lies on the ground—will turn yellow. By using these markers, watermelons can be harvested when their flavor and freshness are at their best.
When harvesting, cut the fruit off the vine using a sharp knife, leaving a little piece of the stem still attached. This preserves freshness and extends shelf life. Watermelons should be handled carefully after harvesting to avoid bruising or injury, since any wounds may compromise their marketability and storage quality. To maintain the fruit’s integrity and guarantee that it reaches consumers in the best possible shape, careful treatment and gentle transportation are crucial.
Cost of Investment Per Acre of Watermelon Farming
| S.N. | Categories | Estimated Cost (NRs.) |
| 1 | Land Preparation (plowing, leveling, pit digging) | 30,000 |
| 2 | Watermelon Seed (800g) | 16,000 (varies) |
| 3 | Fertilizers and Manure | 40,000 |
| 4 | Irrigation | 40,000 |
| 5 | Labor Costs (Planting, maintenance) | 25,000 |
| 6 | Pest & Disease Control | 25,000 |
| 7 | Miscellaneous Costs (Equipment, Mulch, etc.) | 20,000 |
| Total Cost | 196,000 |
Income from 1 Acre of Watermelon Farming
| Estimated Yield/Acre | Market Price (NRs/kg) | Total Income (NRs.) |
| 16,000 kg | 20 | 320,000 |
Profit Analysis for Watermelon Cultivation
Watermelon cultivation involves a total investment cost of NRs. 196,000 per acre, with an estimated total income of NRs. 320,000 from a yield of 16,000 kg sold at NRs. 20/kg. The net profit is calculated as NRs. 124,000 (Total Income – Total Cost), indicating a profitable venture under the given assumptions. To break even, a minimum yield of 9,800 kg is required to cover the total cost of NRs. 196,000. Proper management and optimal growing conditions can further enhance profitability.
Factors Affecting Profit
a). Yield: Higher yields directly increase income.
b). Market Price: Fluctuations in market prices can impact profitability.
c). Cost Management: Reducing input costs (e.g., labor, irrigation) can improve net profit.
d). Quality: High-quality fruits fetch better prices in the market.
