Where to plant watermelon?

All You Need To Plant Watermelon Successfully

Watermelon , botanically known as Citrullus lanatus , is one of the world most consumed fruits. Health wise, it is very valuable by the virtue of the nutrient and mineral one derives from it.

Also its market value is unfathomable especially during the dry season.
Water melon is a tropical plant, which requires a lot of sunlight and water for its growth and development. Below are all you need to plant and have a good yield.

Type of soil to plant watermelon
Water melon requires a well drained, deep and friable soil also with rich in organic matters. Water melon does not grow well on a water-logged soil as this can cause the emergence of fungal diseases but the soil must be wet.

Weather condition that favours water melon
Watermelon requires a lot of sunlight, the dry season is the best season to plant water melon. In cooler climate condition, it requires about three months of constant hot, sunny weather to grow and ripen well. Watermelon grows in full sun, abundant supply of water and nutrient is also essential.

Land preparation for planting watermelon
Conventional tillage practise is needed to enable good root development and also absorption of water. The land should be ploughed and harrowed to make it suitable for the planting condition. A long ridge or mould of 6 feets by 6 feets can be made or planting directly into the soil. Organic manure, such as poultry waste can be incorporated to the soil to make the soil rich in essential nutrients that enhance the growth of the plant.
Planting watermelon seeds
Watermelon seeds can be planted at a rate of 2-3 seeds per hole and the most vigorous stand is left on the field while the weak and unthrifty one is eliminated. The depth of the hole is about 1.5cm and the spacing 6 feets by 6 feets, watermelon needs a lot of space as well.

Germination
Watermelon germinates quickly, the leaves appear at about 3 days after sowing.

Management practices of watermelon after germination.
Watermelon requires a lot of care starting from the day of emergence to harvesting. These include;

Watering: water melon should be watered daily until fruit develops. In a commercial level, a drip irrigation system can be installed to regularly supply the plant with water. Apply water at least once a day.

Mulching: this is done in order to conserve moisture and control weeds, this can be done with straws or polythene nylon or black plastic.

Fertilizer Application: Nitrogenous fertilizer is needed at the early stage of this plant but when fruit develops, phosphorus and potassium based fertilizer is needed mostly as these will enhance the growth and development of the fruit. Apply NPK 15:15:15 after 10 days of planting and SSP and NPK at about 40 days after planting.
Weeding: weeding should be done before the application of fertilizer to discourage competition among the plant and the weeds, this should be done every two weeks.

Pest and disease control: Just like all plants, watermelon has insects and pests that do attack it, however several measures has been suggested to tackle this threat. Laraforce and cyberfore can be used every month to be on the more safer side.The main threat of watermelon is a mildew, this is a fungus disease. The leaves appear as if there is whitish powder on it, it best thrives in damp and humid environment this is why the farm must not be damp.

Sweetening of watermelon: The taste of watermelon can be improved by not applying water at about 10 days before harvesting, this will make the melon sweeter.

Harvesting
Watermelon matures at about 80- 90 days of planting. Ensure ripening watermelons are not in direct contact with the soil to prevent rot and protect fruit from pest and rodents, as the size of the fruit increases, place it on a bed of straw or other mulching material. There are three approaches to know when the watermelon fruit is ripe or not;

The first sign is that the curly tendril at the stem tends to dry up, once it has totally dried up, then the fruit may be said to be ripe.

Another sign is that the light coloured patched at the bottom of the fruit, it is normally green but when the fruit ripens the green colour disappears and it becomes yellowish.

The most popular way is thumbing the fruit, if it makes a higher pitched sound, it means the fruit is unripe but if it makes a dull , hollow sound it means the fruit is ripe.

How to grow Watermelon for Profit – Summary

Growing watermelon –if done rationally and on a scalable basis- can be a good source of income. In a few words, most commercial watermelon growers start the crop from seeds (hybrids) in an indoor protected environment. As they wait for the young seedlings to grow and be ready for transplanting, they prepare the field. They till the land, they make the beds or furrows and they place a black plastic film through the rows. The black plastic film not only helps the soil become warmer but also controls weeds. They also design and place the drip irrigation system. When they are ready for transplanting, they make small holes in the plastic film, where they dig small holes and plant the seedlings. Fertilization, Drip Irrigation and Weed Management is applied in most cases. Thinning is also applied. Commercial watermelon growers remove the malformed or underdeveloped watermelons in order to encourage the plant to devote its resources in fewer but bigger and tastier fruits. Most commercial watermelon varieties can be harvested 78-90 days after transplanting. Harvesting can only be made through hand scissors or knives. After harvesting, watermelon growers plow and destroy the remaining of the crop. They may also rotate the crop, in order to control diseases or prevent soil from depleting.

The restrictive factor when growing watermelon is always the climate. Watermelon plant comes from Africa. It is a plant extremely sensitive to low temperatures and frost. It requires on average temperatures from 18 to 35°C (65 to 95 °F), while soil temperature should not fall below 18°C (65°F).

First of all, it is crucial to decide the growing method as well as the varieties of watermelon that thrive in our area. There are 3 methods to grow watermelons: Growing from seed, growing from non-grafted seedlings and growing from grafted seedlings.

Growing Watermelons From Seed

Watermelons are long-period crops. For growing outdoors, they need on average 100 to 120 days from seeding to harvesting. However, if you are planning to grow watermelon from seed, there are some facts you need to know. First, watermelon seeds require at least 18 °C (65 °F) soil temperature in order to germinate. Second, it is important for the seed to have optimum moisture levels in order to sprout. Over irrigation can be harmful. Some producers water thoroughly the soil a day before sowing and do not irrigate again, until it sprouts. However, this is not a good technique if the soil is too sandy and has difficulties in preserving enough available water.

Watermelon seeds germinate easily in 6-10 days depending on the weather and soil conditions.

In areas with a danger of frost, growers prefer to sow the seeds in seed beds under controlled conditions and then transplanting them into their final positions. They most commonly use turf as substrate for optimum aeration.

Growing Watermelons from Non-Grafted Seedlings

Another commonly used method is growing watermelons from non-grafted plants. If we follow this method, it is crucial to choose carefully the variety of watermelon we are going to plant. If -for example- the fields in our area have problems with diseases, pests, lower or higher pH or salinity levels, then not all varieties can thrive. Some varieties are tolerant to some of those factors, while others are not. The most commonly used varieties are: Charleston Gray, Crimson Sweet, Jubilee, Allsweet, Royal Sweet, Sangria, triploid seedless and Black Diamond types.

Growing Watermelons from Grafted Seedlings

Nowadays, most growers prefer to use grafted watermelon seedlings. Grafting is a commonly used technique by which we join together parts from two different plants, so that they will grow as a single plant. The upper part of the first plant is called scion and grows on the root system of the second plant, which is called rootstock. Eventually, we have a plant that combines all the advantages of its different components. Some producers prefer to grow from seed both the rootstock plant and the scion. Then, they perform the grafting by themselves, while others buy certified grafted seedlings from legitimate sellers. The most commonly used seedlings nowadays are watermelon scions grafted on squash rootstocks.

Soil Requirements and Preparation for Watermelon Cultivation

Watermelons thrive best in rich, slightly sandy soils with pH levels from 5,8 to 6,6. They do not like soggy soils. Heavy clay soils with poor drainage and aeration should be avoided. Watermelon farming requires extensive soil preparation before planting, in order to be profitable and lead to high yields.

The basic soil preparation starts about 5 months before transplanting watermelon seedlings. Farmers plow well at that time. Plowing improves soil aeration and drainage. At the same time, plowing removes rocks and other undesirable materials from the soil. Tillage comes right after plowing. Tillage tractors leave the soil free from weeds which can be harmful for the crop.

One week before planting, many farmers apply a pre-planting fertilizer such as manure or synthetic commercial fertilizer, always after consulting a local licensed agronomist. Since watermelon plants need a lot of space to grow, farmers plant them at predefined distances. Consequently, there is no reason to apply the pre-planting fertilizer to the entire field. A good technique is to mark the areas you are going to plant and then apply the fertilizer towards the lines. The next day is probably the right time to install the drip irrigation pipes. Following the installation, some farmers can apply soil disinfection substances through the irrigation system, in case soil analysis has revealed soil infection problems (ask a licensed agronomist in your area).

The next and most important step (especially in countries with non optimum soil temperature during the planting period) is the linear polyethylene coating. Many producers cover the rows with black or green Infrared- Transmitting (IRT) or black plastic film. They use this technique, in order to maintain the root zone temperature at optimum levels ( >18°C or 65°F) and prevent weeds from growing.

Watermelon Planting and Plant spacing

In many cases, the most suitable period to plant watermelons outdoors, is during the second half of spring. At that time, the danger of frost has passed in most cases. Farmers generally prefer plants aged from 3 to 6 weeks. At this point they have developed maximum 3 veins (ideally 1-2).

After all the preparation steps that started 5 months before planting (plowing, basic fertilization, tillage, installation of the irrigation system and plastic film covering), we can proceed with transplanting. Growers label the exact points on the polyethylene plastic where they will plant the young plants. They then dig holes on the plastic and plant the seedlings. It is important to plant the seedlings at the same depth as they were at the nursery.

As far as the planting distances are concerned, a commonly used pattern for varieties that produce fruits up to 14 kg, is 1m (3,28 feet) distance between plants on the row and 3.5 m (11,48 feet) distance between rows. This pattern will give us 2000-2500 plants per hectare. (1 hectare = 2,47 acres = 10.000 square meters). The distances and the number of plants depend on the watermelon variety, environmental conditions and of course the desired watermelon size that is always dictated by the market. For example, if we plant more seedlings per hectare, we will harvest fruits of smaller sizes. A different pattern for smaller fruit varieties is 1,5 m (5 feet) between rows and 0,6m (1,9 feet) between plants in the row. Following this pattern, we will approximately plant 11.000 plants per hectare. (1 hectare = 2,47 acres = 10.000 square meters).

Watermelons Low Coverage

Due to the fact that in non tropical countries, even in spring, there is always danger for frost or heavy rain, most producers protect young plants with low tunnels coverage. Right after planting, they create tunnels of 50 cm (1.6 feet ) height, using plastic or iron support struts and white plastic covers. In a few words, they create tiny greenhouses so as to maintain the desired microclima and protect the young seedlings from harmful factors.

Approximately 45 days later (depending on the weather conditions), they start to gradually rip the plastic day by day, until they fully uncover the plants. A few days later, they completely remove it from the field. This gradual and incremental tearing of tunnel is very important. Otherwise, the sudden removal of the plastic will stress the plants.

Watermelons Pruning – A controversial method

Some watermelon producers prefer to prune their watermelons, while others claim that pruning delays the development and fruit set of the plant. Those who prune their plants, remove most of the peripheral veins of the plant early, during the first stages of development, when it only has 3-4 veins. With this method, they force the plant to develop further through the main vein. They keep removing excess foliage that prevents proper aeration, during the entire growing period. Thus, they protect the plant from humidity favored infections like Powdery Mildew.

Watermelon Water Requirements and Irrigation Systems

According to FAO, the total watermelon water requirements during the entire growing period range from 400 to 600mm. Of course, the water requirements can be totally different under different weather and soil conditions. For example, heavy clay soils normally need less irrigation sessions than a sandy soil. Additionally, high atmosphere humidity or rainy days may not require irrigation sessions at all. On the other hand, a dry day with very high temperature may require one irrigation session per day.

Many producers in Mediterranean countries like Greece, prefer to irrigate their watermelons 20 minutes per day, during their first stages. During the fruit setting stages, and as the temperature has increased enough (>35 oC), they increase irrigation sessions, due to the extended needs of the plant at these stages. Finally, they reduce irrigation dramatically, and almost stop irrigation during the last stages of maturity. Excess water at these stages will cause the fruit to crack. In some states of the USA, commercial watermelon producers provide on average 25mm of water per week. Many producers prefer to irrigate their watermelons early in the morning during the first stages and late in the evening as the temperature increases.

Generally, watermelons have high water requirements, but watering the foliage has been linked with diseases outbreaks. Excess humidity in general may favor the development of pathogens such as Powdery Mildew. On the other hand, water-stressed plants are more susceptible to diseases.

The most commonly used irrigation system is drip irrigation.

Watermelon Pollination

Watermelon fruit setting relies on the activity of bees and other beneficial insects who distribute pollen. Especially when we grow seedless varieties, placing 1 or 2 strong and healthy hives per 1 hectare is necessary. Manual Pollination can also be a choice if we grow watermelons inside greenhouses or if the natural bee population in our area is not sufficient to pollinate our plants.

Watermelon Fertilizer Requirements

First of all, you have to take into consideration the soil condition of your field through semiannual or annual soil testing, before applying any fertilization or tillage method. No two fields are the same, nor can anyone advise you on fertilization methods without taking into account your soil’s test data, tissue analysis and crop history of your field.

However, we will list the most common watermelon fertilization schemes, used by a considerable number of farmers.

The most commonly used fertilization method is “fertigation”. Producers inject water soluble fertilizers in the drip irrigation system. In this way, they can provide the nutrients gradually and give the plant the proper time to absorb them.

Nowadays farmers make from 0 to 10 fertilizers applications throughout the 3 months growing period (from planting to harvest). Many farmers apply a pre-planting fertilization such as manure towards the rows one week before planting and start the fertigation 2 days after planting. At this point, they apply a Nitrogen- Phosphorus- Potassium 12-48-8 fertilizer, enriched with trace elements (micronutrients). High Phosphorus levels at the first stages will help plants develop a strong root system. Additionally, in many cases micronutrients make it easier for plants to overcome any stress conditions caused by transplanting.

The next 3 applications (1 per week) alternate between 15-30-15 and 12-48-8.

For the next 4 weeks, they apply interchangeably 20-20-20 and Ca(NO₃)₂ keeping a time window of 3 to 4 days between every application.

For the next 2 weeks, they do not apply any fertilizer. At week 11, they apply 20-20-20 until the fruit reaches ⅔ of its final weight. From this point onwards, they start providing watermelons with KNO3 . At the final maturity stage, they change to ‎Κ₂SO4 . At these stages, plants normally have greater needs for Potassium in order to create big, well shaped fruits with high sugar levels.

However, these are just common patterns that should not be followed without making your own research. Every field is different and has different needs. Checking the soil nutrients and pH is vital before applying any fertilization method. You can consult your local licensed agronomist.

Watermelon Pests and Diseases

The first precaution against pests and diseases is crop rotation. The second is to purchase only certified and disease free seeds and seedlings.

Pests

Thrips

Thrips palmi are slender insects that attack watermelons by sucking the sap of leaves. Sunny and hot weather favor the infestation. Thrips management begins with proper precautionary measures. These include, weed control and crop rotation.

A good technique is to constantly monitor their population. If the number is over the tolerable limits, then you can consider to intervene, always after the advice of a local licensed agronomist. There are biological as well as chemical solutions on the market, which of course should always be used under GAP standards and the supervision of a local licensed agronomist

Aphids

Aphids suck the sap and cause the plant to weaken. Leaves start to curl and shrink. Furthermore, aphids transmit several virus diseases.

Tetranychus urticae

This mite primarily appeared in European countries. However, nowadays it is an American problem as well. It damages leaves, stem and fruit. It causes chlorotic spots on leaves. The mites also cause discolouration on fruits, lowering their quality.

Diseases

Anthracnose

Anthracnose is a disease that causes serious damages mostly on leaves and veins. It is caused by the fungus Colletotrichum lagenarium. Cool and wet weather favors the fungus spores. Dry and hot weather conditions stop the disease cycle, which will continue again when weather conditions will be optimal. Symptoms appear primarily on the older leaves causing brown necrotic spots. We may also observe these infestation damages on stems, flowers and fruits.

Anthracnose control begins with proper precautionary measures. These include: weed control and proper distances between plants, along with proper pruning for optimal aeration. The proper nutrient and water levels of the plants can also boost their immunity. Chemical treatment is used only if the problem is severe and always under supervision from a licensed agronomist.

Downy Mildew

Downy mildew is caused by microorganisms of the Peronospora or Plasmopara genus. Symptoms most commonly appear on leaves after rain or during days with high humidity (often during spring). When our plants are infected by downy mildew, we will probably spot yellow or gray spots with mildews underneath. Downy Mildew control always begins with proper precautionary measures. These include: weed control, proper distances between plants along with proper pruning for optimal aeration. Chemical treatment is used only if the problem is severe and always under the supervision of a licensed agronomist.

Powdery Mildew

Powdery Mildew is caused by many different species of fungi. However Erysiphales and Podosphaera xanthii appear to be the most common ones. We can actually see a white powdery mildew on the leaves. As the powdery mildew moves through the vessels, leaves tend to become brown and eventually die. Powdery Mildew control includes the same steps as for Downy mildew. We must always disinfect our tools after we have handled an infected plant, in order to prevent the infection from spreading to healthy plants.

Watermelon Harvest Yield and Storage

Most watermelon varieties reach their full maturity and are ready to be harvested 78 to 90 days after transplanting. When they are ready for harvesting, in most cases we notice a yellow spot on their skin on the surface that is in-touch with the soil. Furthermore, we can observe a dry tendril on the part at which the stem is linked to the vain.

Due to the differientations in pollination time, not all watermelons mature at the same time. Thus, we may have to harvest the same field more than one times.

Watermelons can be harvested only by hand. We must be cautious to cut and not pull the watermelon, otherwise the fruits may crack open, and in this case they cannot be marketed.

A good yield, after some years of experience is 50 to 80 tons per hectare. In commercial watermelon farms, we may expect to harvest 1,5 to 2 full size watermelons per plant.

Watermelons are then transferred to cool but not freezing storage areas with a temperature of 10 °C ( 50 °F).

Do you have experience in growing watermelon? Please share your experience, methods and practices in the comments below. All the content you add will soon be reviewed by our agronomists. Once approved, it will be added to Wikifarmer.com and it will influence positively thousands of new and experienced farmers across the world.

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Wikifarmer Editorial Team

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Georgia watermelon harvest hits full throttle

“It has been an uphill battle this year for farmers,” Kelley says. “But it hasn’t been the steepest they’ve ever climbed.”

Harvest geared up and was expected to hit full throttle right before that quintessential watermelon holiday: the Fourth of July.

“If you bought a watermelon for the Fourth in Georgia, it was probably a Georgia melon,” Kelley says.

Georgia farmers planted about 30,000 acres this year, he says. Yields will be good, but not great, probably 40,000 pounds to 50,000 pounds per acre.

Farmers have received prices “they can certainly live with,” Kelley says, ranging from 14 cents to 18 cents per pound. The crop last year was worth about $55 million.

Drought conditions helped keep disease problems at bay this season, says David Langston, a plant pathologist with the UGA Cooperative Extension. But in recent weeks a disease called powdery mildew has attacked and collapsed vines in some fields.

This turned a relatively low-cost disease year into a moderate to high-cost one.

Responding to market demand over the past decade, Georgia farmers now grow mostly seedless watermelon varieties.

Kelley predicts a new shift in the market in the coming years with the introduction of mini-melons. Weighing about 5 pounds, they are just the right size for an individual. Georgia farmers have already taken note and are growing a small number now.

Big or small, an uncut watermelon can stay fresh a week at room temperature, a little longer if kept over an air-conditioned vent. A sliced melon should be wrapped in cellophane and stored in the refrigerator to keep it crisp.

Miscellaneous melon facts:

• The watermelon is in the Cucurbitacea family and related to the cucumber and squash.

• A watermelon is 90 percent water.

• Native to central Africa, watermelons were first cultivated by ancient Egyptians.

• Farmers plant 1,600 to 1,800 watermelon plants per acre.

• One commercially-grown plant produces one or two melons in the field.

Sukari F1 Watermelon Farming in Kenya: Succeed in Watermelon Business

Watermelon farming in Kenya is a profitable business, that can pay off in the shortest terms. Earn up to 400,000 Ksh in less then three month. Follow the pieces of advice in the article like soil preparation for watermelons or how many watermelon plants per acre should you plant, and your watermelon buyers in Kenya will increase day after day.

Sukari F1 watermelon farming in Kenya. How to succeed in watermelon business?

The proper watermelon farming techniques will help you to increase the incomes. Here are some secrets that will help you.

Watermelon Farming Techniques

Read also: How To Open a CDS Account in Kenya in 2018

As a future watermelon farmer, you should know that watermelons are planted from watermelon seeds. What are the watermelon seeds prices in Kenya? The average price of watermelon seeds is approximately 3,500 Ksh per kilogram. There is also a possibility of planting watermelons on nursery, and transfer them later. It’s up to you which method to choose.

So, now you know the cost of watermelon seeds in Kenya, you should know how many watermelon plants per acre is is needed. Spacing of these juicy fruits usually is 1,5m from row to row and a meter from watermelon to watermelon.

Watermelons require a lot of water, so be ready to make a qualitative irrigation systems for your plants. Otherwise, watermelons will be dry inside. If there is too much watering, the fruits will become watery and tasteless inside. Soil preparation for watermelons requires enrichment with nutrients. You will also have to put manure to the soil, before planting process. Plow diligently, to mix soil and manure well. Best fertilizer for watermelons is natural one.

The soil has to contain alkaline PH, so put a bit lime to the soil. Make sure this procedure is repeated every three years. A small advice – boron, will help you to make watermelons sweet as sugar.

Boron helps watermelons to become even sweeter

Watermelon Farming in Kenya

The expenses of watermelons production are pretty low. One acre of land requires approximately 40,000 Ksh. The most popular types of seeds in Kenya are Sugar Baby, Ealy Scarlet F1, Daytona F1, Zuri F1, Sukari F1 and Pato F1. It is better to choose the hybrid seeds, as in the end you will get the best results. You can find them either at your local market, or order at the Kenya Seed Company. The types of watermelons described above, are resistant to most kinds of plant diseases.

One acre of land can provide you with 15,000 watermelons, weighing from 7 to 13 kilograms. The weight depends on the chosen watermelon breed. Let’s imagine that you have harvested over 10,000 pieces of watermelons per season, and sold it for 100 Ksh per each. That means that you will earn one million in only three months. Which job will provide you with such a sum?

Watermelon business, can bring you an income over one million Ksh

Try selling watermelons to the neighbor countries, like Uganda for a higher price and double your income. 200-300 Ksh for a watermelon, is a normal price there, as planting this kind of fruits there is way more expensive. And the best thing is, that you can harvest watermelons twice a year. Just imagine, half year of work, and half year of constant holidays.

Sukari F1 Watermelon

There are different kinds of watermelon breeds that can easily grow in Kenya. Check out the most popular breeds:

  1. Sukari F1 watermelon hybrid. It is highly in-demand because of the sizes of each fruit that you will get in the end and it’s unique sweet taste.
  2. Golden midget breed, is well-known for it’s golden skin, sweet pink flesh and miniature sizes.
  3. Pato F1 tastes as good as Sukari F1, however the sizes are a bit smaller.
  4. Breed Sweet beauty grows approximately for eighty days and has bright red flesh.
  5. Sugar Baby breed is a small kind of watermelons, maximum weight 3-4 kilograms and ripen on the 80th day.
  6. Charleston grey weight the most – at least nine kilograms, however, they ripen on the 85-110 day.

So, from the provided list of popular watermelon breeds, you can see that Sukari F1 watermelon breed is the best for planting and selling to watermelon buyers in Kenya. Do your best, work hard, and in the end you will get millions Kenyan shillings per watermelon harvesting season. Remember the pieces of advice listed in this article and you will definitely succeed.

Have any other interesting ideas about watermelon harvesting in Kenya and want to give some pieces of advice? Share your thoughts in the comments section below.

Watermelon Farming

Watermelon (Citrullus lanatus) belongs to the Cucurbitaceae family and is a warm season annual plant which produces large and juicy fruits. Fruits are mostly composed of water and can be eaten raw or pickled and the rind is also edible when cooked.

Farming requires minimal management processes and its market is readily available. In Kenya, it is done mostly in hot regions like Makueni, Machakos, Kajiado and the coastal regions. Watermelon can also be grown in highland regions, although the quality of the fruits is inferior compared to those grown in hot regions.

Health benefits and nutritional value of watermelons

  • High in lycopene, a powerful antioxidant which is effective in preventing some forms of cancer and cardiovascular diseases.
  • High in Vitamin A, C and B6.
  • Rich in Potassium which is helps in controlling blood pressure and preventing strokes.
  • Rich in folate, amino acids, among other healthy components
  • Low in calories
  • Very nutritious

ECOLOGICAL REQUIREMENTS

Soil– the crop does well in loamy, well drained soils, rich in nutrients and slightly acidic. If grown in heavy soils, the crop grows slowly and fruit size are usually of low quality.

Temperature– warm temperatures of between 15-30 C are fit for the growth and development of this crop.

Attitude– watermelons can do well at attitudes of up to 1500m asl. However, lowlands are best growing areas.

Rainfall– the crop flourishes in regions with an optimum rainfall of 600mm per cropping season. Irrigation is important in order to ensure consistent moisture availability.

Seed selection

In order to get excellent results, the choice of seeds is very important. Some of the commonly used varieties include Sukari F1, Zuri F1, Kubwa F1, Sugar Baby, Crimson Sweet, and Sweet Rose F1. Hybrid seeds are preferred for production of quality fruits. These are available in agrovets/agro dealers’ shops.

Seed rate

Approximately 500g of seeds is required for direct sowing in a one-acre piece of land.

Spacing

The crop is spaced at 1.5metres between the rows and 1 meter from one crop to the other. The vines require enough space for their spreading.

LAND PREPARATION & PLANTING

Land preparation should be done early to allow for weeds to dry and decompose before planting.

Seeds are usually planted directly in the field. However, it is also possible to first raise them in a seedbed and transplant into the main field although this can cause disturbances to their root systems.

Procedure

  1. Spray weeds with CATAPULT® 480SL 200ml/20L.This kills both the broadleaf and grass weeds.
  2. Plough land and make it level with a fine tilth.
  • Mix soil with manure and DAP. For efficient and improved nutrient uptake as well as stabilizing soil pH, mix 1kg HUMIPOWER® with 50kg DAP and /or 1 ton of manure.

  1. Make holes at a spacing of 1.5m by 1m and place 2 seeds at a depth of about 2-4cm.
  2. Cover seeds with loose soil.

Tips!

  • Use certified seeds.
  • Seeds soaked in OPTIMIZER® 20ml/1L overnight prior to planting germinate uniformly and faster.
  • The crop needs at least 6-8 hours of direct sunlight which is very essential for fruit development.
  • Germination occurs in 7 days.

Weeding

Weeds can significantly lower the productivity potential of the crop as they compete with crop for nutrients, water and light and harbor diseases and pests, which lowers yields. Therefore, proper weed control is very important for good yield and it also makes harvesting easier. This can be done by shallow cultivation. Hand weeding is recommended when the crop has grown enough to cover the soil.

Pruning

Excess fruits should be pruned in order to allow the right number of fruits to develop properly and obtain marketable quality. All of the unmarketable fruits i.e., the misshapen and blossom-end rot fruits are removed.

Irrigation

Watermelons require relatively a lot of water, therefore, sufficient irrigation should be done in order to maintain moisture consistency. If this is not done, the fruits dry inside while too much watering makes the fruits to become tasteless and watery.

Irrigation can be done through furrow, overhead or drip irrigation.

Tips!

  • Fruit splitting/cracking may occur as a result of excessive irrigation after the crop had been water stressed.
  • Irrigation should be reduced as the fruits reach harvesting stage. It should be stopped about two weeks prior to maturity.

FERTILIZER APPLICATION

In order to achieve optimum yields, timely application of both basal and foliar fertilizers is highly recommended. Manure should be added especially for soils with little or no organic matter. Proper nutrition during the initial growth stages of crop helps boosting nutrients and make the fruits grow bigger.

During planting

Apply 50kg of DAP in one acre before planting. Alternatively, place a teaspoonful of fertilizer into each planting hole, mix it thoroughly with the soil to make sure that the fertilizer doesn’t burn the seeds and then place the seeds.

DAP is preferred because it contains relatively higher levels of phosphorus which helps the crop with root development. Other phosphatic fertilizers like TSP can be used.

Young plants should be sprayed with LAVENDER SUPER STARTER® 20ml/20L or GATIT SUPER START® 50g/20L one week after germination, which promote early crop establishment among other benefits.

Top dressing

Use CAN 3-4 weeks after sowing. Apply 1 teaspoonful of the fertilizer at the base of each plant in a ring or along the rows, about 15cm away from the plant at a rate of 50-100kg per acre.

CAN fixes nitrogen in the soil which increases the green color of the leaves, responsible to make food for the plant. Other nitrogenous fertilizers like urea can also be used.

Spray the crop with GATIT SUPER GROWTH® 50g/20L or LAVENDER SUPER GROWTH & VEGETATIVE® 20ml/20L.

During the flowering and fruiting growth phases, spray the crop with GATIT SUPER FLOWERS & FRUITS® 50g/20L or DIMIPHITE® 20ml/20L or GOLDCHANCE MULTISUPER K® 50g/20L or LAVENDER SUPER FLOWERS & FRUITS® 20ml/20L.These are rich in nutrient elements which promote production of quality fruits.

Tips!

  • Soil analysis is highly recommended in order to determine the soil fertility level.
  • All basal fertilizers should be mixed with HUMIPOWER® at a rate of 1kg of HUMIPOWER® into 50Kg of fertilizer.
  • OPTIMIZER® is an organic biostimulant which is essential for plant growth and stress management. It can be applied at all or any growth and development phase of the crop.

Yield

The yield varies according to the variety and general maintenance of the crop. However, an acre of land, in favourable ecological conditions and under good maintenance can produce 20 to 35 tonnes of watermelons.

Crop rotation

The crop can be rotated with non- cucurbitaceae crops like cereals, legumes or brassicas. This helps in pest and disease management as it breaks their development cycles, among other benefits.

MAJOR PESTS & DISEASES

Pests

Cutworm– these are brown biting and chewing pests mostly found in the soil near the plant root zone which cut down young and tender stems. Heavy infestations cause significant crop loss.

Drench soil with PROFILE® 440EC 60ml/20L or PENTAGON® 50EC 20ml/20L

Melon fly– it attacks the young fruits altering their cell development and multiplication leading to production of deformed fruits as well as immature dropping of the infested fruits.

Spray KINGCODE ELITE® 50EC 10ml/20L or PROFILE® 440EC 30ml/20L or OCCASION STAR® 200SC 3ml/20L

Red spider mites – these are a great problem in dry and hot conditions. They feed by piercing and sucking while damaging the crop. Attacked leaves have a stippled appearance which turn yellowish to whitish and dry up. Plants under water or drought stress are more likely to suffer serious damages by the pest. They form webs on the undersides of the leaves.

Spray ALONZE® 50EC 5ml/20L or BAZOOKA® 18EC 10ml/20L or OCCASION STAR® 200SC 3ml/20L

Whiteflies – these suck plant sap and excrete honeydew where molds grow, which affects plant growth and vigour. Affected plant loses its vitality due to sap sucking resulting yellowing, downward curling and finally drying of leaves. The tobacco whitefly is considered a major pest due to its ability to vector various virus diseases which cause considerable damage to watermelons.

Spray TAURUS® 500SP 10g/20L or LEXUS® 247SC 8ml/20L or KINGCODE ELITE® 50EC 10ml/20L

Leaf miners– the larvae mine under the leaf surface, creating white mines which are irregular in shape and increase in width as the larvae mature. This reduces photosynthetic area eventually leading to leaf wilting.

Spray ALONZE® 50EC 5ml/20L or ESCORT® 19EC 10ml/20L or LEXUS® 247SC 8ml/20L or OCCASION STAR® 200SC 3ml/20L

Epilachna beetles – adults and larvae feed on leaves leaving a fine net of veins and the damaged leaves shrivel and dry up. Young plants can be entirely destroyed while the older ones can tolerate considerable leaf damage. This beetle is a vector of squash mosaic virus.

Spray KINGCODE ELITE® 50EC 10ml/20L or SINOPHATE® 750SP 20g/20L or LEXUS® 247SC 8ml/20L

Aphids– they feed by piercing and sucking the plant sap and reproduce very fast and thus, if not controlled, they cause significant damages. Infested leaves curl and crinkle. As they feed, they excrete honeydew which facilitates the development of sooty mold which reduces photosynthetic area. Stunted growth is noted.

Spray KINGCODE ELITE® 50EC 10ml/20L or PENTAGON® 50EC 10ml/20L or LEXUS® 247SC 8ml/20L

Thrips– both the adult and nymph are destructive. They feed on the leaves and most preferably flowers by sucking the sap thus causing damages which may lead to flower damage/abortion.

Spray ALONZE® 50EC 5ml/20L or BAZOOKA® 18EC 10ml/20L or OCCASION STAR® 200SC 3ml/20L

Nematodes– these are microscopic parasites found in the soil. Infestation leads to wilting of plant, and when the infested plants are pulled from the soil, the roots are seen to be distorted, swollen and bearing knots/ galls which eventually rot causing an eventual death of the plant.

Drench the planting holes with ALONZE® 50EC 10ml/20L or mix basal fertilizer, 50kg with 2kg of ADVENTURE® 0.5GR.

Diseases

Damping off– this is a soil borne disease. Diseased seeds do not germinate while seedlings rot and eventually die. White cottony growth is evident on the roots of the infected seedlings.

Drench the planting holes with PYRAMID® 700WP 100g/20L

Powdery mildew -symptoms first develop as whitish talcum like powdery growth on upper leaf surface and as infection progresses, the stems also get infected. Severely infected parts turn yellowish and eventually wilt.

Spray RANSOM® 600WP 15g/20L or DOMAIN® 250EC 10ml/20L or ABSOLUTE® 375SC 10ml/20L

Anthracnose– symptoms are mostly noticeable on fruits as circular black or brown sunken lesions. When wet the centres of the lesions become purplish coloured due to a mass of fungal spores. However, water soaked lesions are also seen on the leaves and stems. On the stem they can girdle the stem causing wilting of the vines.

Spray RANSOM® 600WP 15g/20L or DUCASSE® 250EW 20ml/20L or ABSOLUTE® 375SC 10ml/20L or KATERINA® 720SC 40ml/20L

Downy mildew– infection leads to formation of yellow patches on the underside of the leaf. These diseased leaves eventually turn brown and fall off. Infected plants get stunted and die while the produced fruits may not mature and therefore have a poor taste.

Spray GEARLOCK TURBO® 250WP 25g/20L or FORTRESS GOLD® 720WP 40g/20L or TOWER® 720WP 50g/20L or KATERINA® 720SC 40ml/20L

Watermelon Mosaic – this is a viral disease. The virus is mechanically transmitted and also spread by several species of aphids in non- persistent mode. Leaves show symptoms of reduced size, patches of dark-green tissue alternating with yellow-green. Generally, the plant becomes stunted and fruits develop water soaked lesions with central solid spots.

Control aphids by spraying KINGCODE ELITE® 50EC 10ml/20L or PENTAGON® 50EC 10ml/20L or LEXUS® 247SC 8ml/20L

Leaf spots – infection causes development of spots on leaves which are angular in shape and variable in size due to the size of the leaf veins. Initially these spots are water soaked.

Spray RANSOM® 600WP 15g/20L or CHARIOT® 500SC 20ml/20L or ABSOLUTE® 375SC 10ml/20L or MILESTONE® 250SC 10ml/20L

Fusarium wilt– initially, symptoms appear as chlorosis of the leaves and as infection continues, leaves begin wilting from bottom to top. The brown vascular discolouration inside infected stem or root leads to the death of plants.

Drench with GREENCOP® 500WP 100g/20L

Foliar spray PYRAMID® 700WP 50g/20L or ABSOLUTE® 375SC 10ml/20L after every 2 weeks.

Tips!

  • In all foliar sprays, mix the chemical with INTEGRA 3ml/20L, which is a sticker, spreader and penetrant which increases the efficacy of the product.
  • Use CADILAC® 800WP 50g/20L, which is a preventative fungicide against diseases including anthracnose, downy mildew and leaf spots.

HARVESTING

This starts about 3 to 4 months after planting depending on the variety and the ecological factors. Harvesting is best done early in the morning when field heat is low and the fruits are most turgid.

Maturity indicators

They include the following;

  • dull hollow sound when the watermelon fruit is tapped with the knuckles
  • cracking of the stem near the mature fruit
  • skin colour change from white to cream or pale yellow where the fruit has been resting on the soil
  • breakup of green bands at the blossom end of the fruit
  • death of the tendrils near the fruit as it reaches maturity
  • skin gets resistant to penetration by the thumbnail and is rough to the touch

Tips!

  • Fruits should be cut off the vine using a sharp object like a knife rather than pulling, twisting or breaking off.
  • If the fruits are harvested while immature, the red color forms but the flesh does not develop the acceptable sweetness since sugar content does not increase after harvest.

HANDLING, STORAGE & TRANSPORTATION

Minimum handling of the fruits should be ensured because they are quite fragile and prone to breakages and bruising.

In storage, temperature management is very crucial for optimum quality of the fruits. They are not adapted to long storage periods.

Fruits should not be tossed up onto the truck and they should be arranged properly to minimize any movement, which protects the fruits from interior bruising.

Watermelons should not be transported in closed trucks or stored with ethylene-producing produce like bananas as this causes them to break internally, the flesh becomes water-soaked and soft and losses its sweet flavour.

NB; Do not store harvested watermelons on the sun.

PHYSIOLOGICAL DISORDERS

These are conditions that are caused by non-pathogenic agents. They can result either due to one or a combination of nutritional, environmental or genetic factors. They include the following;

Blossom-End- Rot (BER)

This is deterioration of the blossom end of the fruit which starts with softening, slight shriveling, browning, blackening with increased shriveling, and sometimes secondary decay. It is caused by lack of calcium nutrition and moisture stress. Application of calcium-rich fertilizers like FERRARI GOLD and maintenance of moisture consistence are recommended.

Sunscald /sunburn

This occurs as a result of exposure to intense solar radiation which causes dehydration and overheating damage of the rind tissue.. Sunburns most occur in varieties that produce fruits with dark-green rinds. Covering the fruits with materials like straw or the crop vines can prevent this condition.

Bursting/Cracking

During a dry period the rind becomes fairly inelastic and when this is followed by irrigation or rainfall, large amounts of water are absorbed by the fruit, forcing the rind to burst at its weakest point. Proper nutrition and correct irrigation reduces the occurrence of this disorder.

Misshapen fruits (gourd or bottle-necked)

This is caused majorly due to moisture stress and is common in varieties which produce long fruits. Correct irrigation is recommended.

White heart

Usually white streaks or bands of unwanted flesh at the central part of the fruit forms which is caused by excessive moisture and excessive nitrogen during fruit maturation. Avoid excessive use of nitrogenous fertilizers especially during fruiting stage and ensure correct irrigation.

Misshapen (pear-shaped fruit)

This condition can be as a result of poor pollination which causes restricted growth at the stem end due to absence of developing seeds. It can also happen if temperatures are lower than expected. Increasing the number of bee hives around the farm and using environmentally friendly agrochemicals help in increasing the number of pollinators thereby promoting pollination.

Hollow heart

This disorder is indicated by cracks in the heart/central part of the fruit due to increased growth rate in response to ideal growth conditions facilitated by ample water and warm temperatures.

Rind necrosis

It is an internal disorder of the watermelon rind in which brown, corky, textured spots on the rind form, which may enlarge to form large bands of discoloration that rarely extended into the flesh. Bacterial infections and drought stress have been reported to cause this disorder.

Tips!

  • Watermelons of any variety can be misshapen especially if they lie on uneven ground or get damaged while small in size.
  • OPTIMIZER® is an organic biostimulant which is essential for plant growth and stress management. It can be applied at all or any growth and development phase of the crop.

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