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How to Plant, Grow, and Harvest Watermelon


growing watermelon

Watermelon, scientifically known as Citrullus lanatus, is a juicy fruit that is widely enjoyed in various culinary traditions around the world. Although its origins can be traced back to Africa, watermelon is now cultivated and consumed globally, bringing its refreshing sweetness and vibrant colors to our plates.


Watermelons come in different varieties, but the most common ones include seedless, picnic, and yellow-flesh watermelons. Seedless watermelons are favored for their convenience, as they eliminate the need to deal with pesky seeds. Picnic watermelons are larger and ideal for sharing with a group, while yellow-flesh watermelons offer a unique twist with their golden-hued interior.


In addition to being a delicious summer treat, watermelon also offers several health benefits. It is hydrating and low in calories, making it a refreshing choice for hot days. Watermelon is also a good source of vitamins A and C, as well as lycopene, an antioxidant that may promote heart health.


Growing watermelon in your own garden can be a rewarding experience. Not only will you have a ready supply of this juicy fruit, but you'll also witness the beauty of the sprawling vines and vibrant fruits in your backyard.


In the following sections, we'll explore how you can plant, grow, and harvest watermelon in your garden, ensuring that you never run out of this delightful fruit when you're craving a sweet and hydrating treat.



Optimal Growing Conditions for Watermelon - Climate, Sunlight, and Soil Requirements


how to grow watermelon

Climate Requirements

Watermelon (Citrullus lanatus) thrives best in areas with long, warm growing seasons. It is a heat-loving plant, so it is essential that the average temperature of the growing season remains between 70-85°F. Regions with a growing season of at least 80-100 frost-free days are ideal for watermelon cultivation.


Sunlight Requirements

Sunlight is another crucial aspect of watermelon growing conditions. These plants need full sun to grow properly. This means that your watermelon plants should receive at least six to eight hours of direct sunlight each day. The more sunlight they get, the better they will grow and the more fruit they will produce.


Soil Requirements

When it comes to soil, watermelons prefer a well-drained, sandy or silt loam soil rich in organic matter. The soil should have a pH between 6.0 and 6.8. Watermelons have deep roots, so the soil should be loose and deep – at least one foot deep, but preferably two.

A key aspect of soil preparation is ensuring the soil is warm enough.


This is vital because watermelon seeds need a minimum soil temperature of 70°F to germinate, with 90°F being optimal. You can raise the soil temperature by using black plastic mulch on the soil surface, which also helps retain soil moisture and suppress weeds.


In conclusion, to achieve the best results in growing watermelons, consider all these factors: the climate should be warm, the location must be sunny, and the soil should be well-draining, rich in organic matter, and have the right pH. These conditions collectively create the optimal environment for growing bountiful and delicious watermelons.



Step-by-step Guide to Planting Watermelon


how to grow watermelon

When to Plant – Best time of the year for planting Watermelon


Watermelon is a warm-season crop and needs temperatures of at least 70°F to thrive. Therefore, the best time to plant watermelons is in the late spring or early summer when the threat of frost has passed, and soil temperatures have adequately warmed.


For most regions, this means planting watermelons sometime between April and June. However, these timelines can vary based on your local climate and the length of your growing season. For instance, if you live in a region with a short growing season, you may need to start your seeds indoors or opt for a variety that has a shorter time to maturity.


A helpful tip to ensure your soil is warm enough is to touch it with your bare hands. If you can keep your hand on the soil for a minute without feeling uncomfortable, it is likely warm enough for watermelon seeds.


It's also worth noting that watermelons require a long growing period – generally 70 to 85 days from planting to harvest for most varieties. Therefore, it's important to ensure your chosen planting time allows for this extended growth period without the risk of early frosts in fall, which can harm the plants.


Remember, getting the timing right for planting watermelons is crucial. An appropriately timed planting leads to healthier plants and a better chance of a bountiful and tasty harvest.



Seed Selection – Choosing the right seeds for your garden


The selection of appropriate watermelon seeds significantly influences your garden's productivity. There's a wide array of watermelon varieties available, each differing in size, color, texture, and growth period. Therefore, it's crucial to make a choice that complements your preferences, garden space, and climate conditions.


Choose a Variety: Watermelons are broadly classified into four categories: Picnic, Icebox, Seedless, and Yellow/Orange. 'Picnic' varieties are large, ideal for families or gatherings. 'Icebox' types are smaller and perfect for small households. 'Seedless' variants, as the name suggests, lack hard black seeds, while 'Yellow/Orange' types bear fruits with unusual, vibrant flesh colors.


Consider the Maturity Period: Varieties also differ in their maturity period, ranging from 70 to 90 days. If your growing season is short, opt for a variety with a shorter maturity time.


Space Availability: Large watermelon varieties require more space to sprawl compared to smaller ones. Choose a variety suitable for your garden's size.


Disease Resistance: Some seed varieties are bred to resist specific diseases. If you've struggled with diseases like Fusarium wilt or anthracnose in your garden, consider a resistant variety.


Always source your seeds from reputable suppliers to ensure their quality. The seed packets typically provide detailed information about the variety, including its growth habits, maturity period, and disease resistance. This information is crucial in guiding your decision to select the best seeds for your garden.



Site Preparation – How to prepare the garden bed or pot for planting


growing watermelon

Preparing the site for your watermelons is a critical step that can significantly impact the success of your crop. Proper site preparation creates an ideal environment for your watermelons to thrive.


Location: Watermelons require plenty of space to grow due to their vining habit. A solitary spot in your garden, where the plant can freely sprawl, is ideal. Remember that these plants love the sun, so ensure your chosen spot gets at least six hours of sunlight each day.


Soil Preparation: Watermelons prefer a well-draining soil with a neutral to slightly acidic pH (between 6.0 and 7.0). Begin by testing your soil's pH to ensure it falls within this range. You can amend alkaline soil with sulfur or acidic soil with lime to adjust the pH. Incorporate organic matter, like compost or well-rotted manure, into the soil to increase its fertility and improve drainage.


Forming Hills: Watermelons are typically grown on mounds or hills. These hills should be spaced about 2-3 meters apart for standard watermelon varieties and 1 meter apart for smaller varieties. To form a hill, pile soil up to about a foot high and 2 feet across. The top of the hill is where the seeds will be planted.


Watering the Soil: Once the hills are formed, water them well. The soil should be adequately moist at planting time.


Preparing the site well in advance of planting gives the soil time to settle and the amendments time to start working. A well-prepared site can significantly enhance the growth and productivity of your watermelon plants.



Planting Process - Detailed Steps on How to Plant watermelon Seeds or Seedlings


The planting process for watermelons involves several steps, each playing a crucial role in the development of your plants. Here's a breakdown:


Seed Soaking: Before planting, soak your watermelon seeds in warm water for about 24 hours. This process can accelerate germination by softening the seed coat and allowing moisture to reach the embryo more quickly.


Planting the Seeds: Once your hills are prepared and the soil is adequately warm, plant the seeds. Place 3-4 seeds about 1 inch deep in each hill. If you're using seedlings, plant them in the same manner. Planting seeds or seedlings in a group ensures that at least one will sprout successfully.


Thinning: After the seeds have sprouted and developed a set of true leaves, usually about a week or two after planting, it's time to thin your plants. Thinning helps prevent overcrowding, which can lead to poor fruit development and increased disease pressure. Leave the strongest, healthiest seedling in each hill, and remove the others.


Watering: After planting, water the area thoroughly. Watermelons have deep roots, so it's essential to give a generous amount of water. However, avoid overwatering as it can cause the seeds to rot.


Mulching: Apply a layer of straw or plastic mulch around the plants. Mulch helps retain soil moisture, suppresses weeds, and keeps the fruit clean. If using plastic mulch, black is a good choice as it also helps warm the soil.


By following these steps, you can set your watermelon plants off to a good start. Remember that patience is key: Watermelons are not quick-growers, but the sweet, juicy fruits they produce are worth the wait.



Care for Growing Watermelon


how to grow watermelon

Watering – How often and how much to water the plants


Watering is an essential aspect of watermelon care. Getting the watering right can make a difference between thriving plants and lackluster ones. Here's a guide on how to keep your watermelon plants well-watered:


Frequency: Watermelon plants require regular and deep watering. On average, watermelon plants need 1 to 2 inches of water per week. This amount should be adjusted based on your local climate and weather conditions. In particularly hot or dry conditions, more frequent watering may be required.


Soil Moisture: Watermelons prefer evenly moist soil. The soil should be saturated but not waterlogged. After watering, the top six inches of soil should be moist, which encourages the plant to develop a deep and healthy root system.


Watering Technique: When watering, try to avoid wetting the leaves and vines, as this can promote disease. Use a soaker hose or drip irrigation to deliver water directly to the soil at the base of the plant.


Signs of Overwatering and Underwatering: Keep an eye out for signs of overwatering or underwatering. Wilting leaves can be a sign of both, but if the wilting persists after watering, it may indicate overwatering. On the other hand, yellowing leaves and stunted growth can indicate underwatering.


Watering During Fruit Development: As the fruit begins to develop, the plant will need more water. Continue to keep the soil evenly moist. Once the fruits are the size of a tennis ball, you can reduce watering to help concentrate the sugars in the fruit. However, do not allow the plants to wilt.


Remember, regular watering is key for watermelons. Inconsistent watering can lead to issues like poor fruit development and blossom end rot. A well-watered watermelon plant can produce sweet, juicy fruits to enjoy all summer long.



Fertilizing – The type of fertilizer needed and how to apply it


Fertilization plays a significant role in the healthy growth and development of your watermelon plants. Below is a guide on how to properly fertilize your watermelon garden:


Type of Fertilizer: Watermelons require a nutrient-rich soil. They particularly benefit from a balanced fertilizer that contains Nitrogen, Phosphorus, and Potassium. An N-P-K ratio of 10-10-10 is generally recommended for watermelons. Additionally, watermelons can also benefit from the addition of organic matter or compost to the soil.


Applying the Fertilizer: When your watermelon plants have established themselves and you see the first true leaves, you can start to apply the fertilizer. Scatter the granular fertilizer around the base of the plants, taking care not to let the fertilizer touch the plants directly as this can cause burns.


Fertilization Schedule: Following the initial application, you should apply fertilizer every 3-4 weeks. This will provide your plants with a steady supply of nutrients throughout the growing season.


Side Dressing: When the watermelon plants start to produce flowers, side-dress the plants with a high-nitrogen fertilizer to encourage vigorous growth and the development of large, sweet fruits.


Watering After Fertilization: Always water the plants well after applying fertilizer. This helps to distribute the nutrients throughout the soil and allows them to be readily available to the plants.


Fertilizing your watermelon plants will not only aid in the overall development of the plant but will also significantly improve fruit size and quality. Keep in mind, too much fertilizer can harm your plants, so apply it sparingly and according to the product's instructions.



Disease and Pest Control – Common diseases and pests that can affect Watermelon, and how to manage them


Watermelon plants, like any other, can be susceptible to various pests and diseases. Here is an outline of common threats to watermelon and the best strategies for managing them:


Aphids: These small insects feed on plant sap, which can stunt growth and lead to sooty mold. They can be controlled using natural predators like ladybugs or through the use of insecticidal soaps.


Cucumber Beetles: These beetles can damage both the plant and fruit. Use floating row covers to protect your plants and remove any beetles you see immediately.


Powdery Mildew: This fungal disease appears as a white powdery substance on the leaves and can inhibit photosynthesis. It can be managed with proper airflow and by using a fungicide if necessary.


Anthracnose: This is another fungal disease that can cause wilting and death of the plant. It presents as dark, sunken spots on the leaves, stems, and fruit. Control strategies include crop rotation, removing infected plant debris, and applying a suitable fungicide.


Fusarium Wilt: This soil-borne disease causes wilting and yellowing of the leaves, and eventually plant death. Plant resistant varieties, rotate crops, and remove and destroy infected plants to manage this disease.


Nematodes: These are microscopic worms that attack the roots of the plants. They can be managed by crop rotation and solarizing the soil before planting.


By recognizing these common diseases and pests, you can apply appropriate measures to protect your watermelon crop. Remember, a healthy plant is the best defense against pests and diseases, so providing optimal care is critical for your watermelon's success.



Harvesting Watermelon


how to grow watermelon

When to Harvest – Identifying signs that the watermelon is ready for harvesting


Ground Spot Check: The first sign that a watermelon is ready for harvest is the change in color of its ground spot - the part of the watermelon that is in contact with the ground. As the watermelon ripens, the ground spot transitions from white to a creamy yellow color.


Tendril Observation: The tendrils, or small curly vines, located near the stem of the watermelon provide another ripeness indicator. When the watermelon is fully ripe, these tendrils will change from a green color to a brown, dry appearance.


Surface Appearance: A ripe watermelon will have a dull surface, as opposed to a shiny one. If the watermelon's surface is still shiny, it is probably not yet fully ripe.


Field Spot: The field spot is the area of the watermelon that was laying on the ground. If this spot is a dark, creamy yellow color, the watermelon is probably ripe.


Understanding the right time to harvest is vital for maximizing the flavor of your homegrown watermelons. Observing these signs will help ensure that each watermelon is harvested at the peak of its sweetness.



How to Harvest – Techniques for harvesting watermelon to prevent damage to the plant and fruit



Pruning Shears or a Sharp Knife: To begin, you will need a pair of clean pruning shears or a sharp knife. A clean cut helps to reduce the chances of disease transmission to the watermelon vine.


Clean Cut: Approach the watermelon and locate its stem. Make a clean cut through the stem, ensuring you leave a few inches. Do not tug or tear the watermelon from the vine, as this can damage both the fruit and the plant.


Handling the Harvested Watermelon: Handle the harvested watermelon with care. Despite their size, watermelons can bruise easily, affecting their quality and storage life. Never drop or toss the fruit.


Immediate Use: If you plan on consuming the watermelon shortly after harvesting, you can cut it from the vine with a shorter stem. However, if you plan on storing the watermelon, leaving a longer piece of stem attached can help increase its storage life.


By following these steps, you can ensure a successful harvest of your watermelons, while keeping the plants healthy for future fruit production.



Post-Harvest Care and Storage – How to store and preserve watermelon for maximum freshness and longevity


Watermelon, due to its high water content and delicate nature, requires special care and consideration in post-harvest handling and storage. Here's how you can preserve your freshly picked watermelons:


Cool Down Immediately: If possible, cool down the harvested watermelons as quickly as possible. This step helps to slow down the fruit's ripening process and extends its storage life.


Store Whole Watermelons Properly: Whole watermelons should be stored in a cool and dry place, away from direct sunlight. Ideal storage temperatures range from 50 to 60 degrees Fahrenheit. Be careful not to store them in a humid environment as it can promote mold growth.


Handle With Care: While watermelons may seem robust due to their size, they can get bruised quite easily. Any scratches, cuts, or bruises can lead to faster spoilage. Always handle your watermelons with care.


Storage of Cut Watermelon: Once cut open, watermelon's shelf life drastically decreases. Cut watermelon should be covered with plastic wrap or stored in an airtight container and kept in the refrigerator. It's best to consume cut watermelon within three to five days.


Remember, homegrown watermelons won't have the same shelf life as those you buy from a store, as commercial varieties are often bred for longer shelf life. By following these post-harvest care and storage steps, you'll ensure you enjoy your delicious, sweet, and juicy homegrown watermelons for as long as possible.



Frequently Asked Questions (FAQ)


how long does it take for watermelon to grow?

The time it takes for watermelons to grow from planting to harvest can vary based on the specific variety and the growing conditions, but generally, watermelons require a long growing season and take about 70 to 90 days to mature.

After planting the seeds, germination usually occurs in about 7-10 days, and the first female flowers (which develop into the fruit) will appear after about 35-50 days. Once pollinated, the fruit will begin to develop. This is the longest part of the process, with the fruit typically taking another 35-45 days to fully mature.

Do watermelons grow on trees?

No, watermelons do not grow on trees. Watermelons are a type of fruit known as a pepo, and they grow on a sprawling vine on the ground. These vines are a type of plant known as a trailing vine, and they are members of the Cucurbitaceae family, which also includes squash, cucumbers, and pumpkins. The watermelon plants need a lot of space to grow due to their sprawling nature, and they typically have a growth habit that covers a lot of ground.



Recap and Final Thoughts: Time to Start Planting, Growing, and Harvesting Watermelon


In this comprehensive guide, we have walked you through the important stages of planting, growing, and harvesting watermelon.


Optimal Growing Conditions: Watermelons prefer warm temperatures, full sunlight, and well-draining soil rich in organic matter.


When to Plant: The best time to plant watermelon seeds is in the spring when soil temperatures reach at least 70°F.


Seed Selection: Choosing disease-resistant varieties and hybrids can make your growing experience more successful.


Site Preparation: Preparing your garden by tilling the soil and adding organic compost can boost your yield.


Planting Process: Watermelon seeds should be planted 1 inch deep in hills or rows.


Watering: Watermelons need a lot of water, but the watering should be done deeply and infrequently to encourage deep root growth.


Fertilizing: Regular fertilization with a balanced fertilizer will help the plants to grow strong and healthy.


Disease and Pest Control: Regular inspection and early intervention are the keys to preventing diseases and pests from damaging your watermelon plants.


When to Harvest: Watermelons are usually ready for harvest 70 to 90 days after planting. Look for signs like a dull hollow sound when tapped, a dried tendril, and a yellow underbelly.


How to Harvest: Use a sharp knife or garden shears to cut the fruit from the vine. Try not to pull or tear the fruit away, as this could damage both the fruit and the vine.


Post-Harvest Care and Storage: Store harvested watermelons in a cool, dry place. They can last up to two weeks if stored correctly.


Growing your own watermelons can be an exciting and rewarding venture. Not only will you have delicious and juicy watermelons at the end of the season, but you'll also experience the satisfaction of having grown them yourself. So, why not try it out? With the right care and attention, your watermelon plants can thrive, providing you with a bountiful harvest to share with family and friends.