Did you know that among the variety of greenhouse crops, watermelon occupies not the last place. Of course, it is grown in this way not for industrial purposes, and not in the south, but it shows excellent results and is quite satisfied with the taste of its bold owners. However, the agricultural technology of greenhouse plantings is somewhat different from growing in open ground, and before planting a watermelon in a greenhouse, you need to find out exactly what.
Choosing a variety for growing watermelon in a greenhouse
Among the variety of varieties offered by modern breeding, only those that have the shortest ripening period and small fruits, up to 2-3 kg, are suitable for greenhouse cultivation. This may be familiar to many "Spark". From germination to harvest, they have about 80 days, and with a small weight of the berry, high taste qualities are noted. It is not worth aiming at varieties with a longer growing season, just for the reason that you can never wait for the harvest.
Planting seedlings of watermelon
In mid-April, the time is right to plant watermelon seeds for seedlings. To do this, prepare small, better peat pots, with a diameter of 10 cm and a nutritious soil mixture (potassium sulfate and wood ash are added to the existing soil). In each cup, at a depth of 2 - 3 cm, 1 - 2 watermelon seeds pre-soaked in warm water are placed and put on the south window. Even though the seeds germinate at temperatures above 17°C, the room temperature should be between 25 to 35°C during the day and 18 to 20°C at night to allow the plants to develop well.
For the entire period of growth of watermelon seedlings, it is good to carry out one, preferably two top-dressings with complex mineral fertilizer, the first of which should take place two weeks after sowing the seeds. As the plants develop, the pots are moved apart so that the seedlings do not touch each other with leaves. As soon as 3-5 true leaves form on young plants, they can be planted in a greenhouse. This usually happens after 25 - 35 days.
Planting watermelons in a greenhouse
If the greenhouse is heated, watermelons can be planted as early as mid-May, but if not, you should wait until the stable temperature outside reaches 20 - 25 ° C.
Seedlings are planted in pre-prepared ridges, 20 cm high and 40–50 cm wide, at a distance of 40–50 cm from each other. At the same time, the plant is not buried.
An important nuance is the height of the greenhouse and the humidity maintained in it. In order for watermelons to feel comfortable, humidity indicators should be maintained at the level of 60 - 70%, and the ceiling height of the greenhouse should be - 180 - 200cm.
Caring for watermelons in a greenhouse
Since the watermelon has long lashes, it must be tied up. He himself will not cling to the twine. Therefore, making a daily bypass of the beds, you need to wrap the regrown ends of the plants around the trellis counterclockwise. In addition, in greenhouse culture, watermelon is formed into one stem, so everything that has formed up to a height of 40 cm (side shoots, flowers) is plucked out.
60 days after planting, the plants begin to bloom. Male flowers appear first on them, after 10 days - female ones. During this period, pollination is very important. In regions with a warmer climate, greenhouse windows are periodically opened for this, providing an opportunity for insects to do their work; in the northern regions, pollination is done manually. To do this, they pluck the male flower and apply it with stamens to the female. How to distinguish male and female flowers? On the female, a small watermelon is initially visible.
If pollination has occurred, the ovary will begin to grow and bend down; if it has not happened, the flower will stretch upwards. Here, too, you need to be alert. And as the watermelons begin to reach the size of a plum, counting up from each of them 7 leaves, cut off the tops of the lashes. The best option is considered if one fruit ripens on one plant, if there are several berries on the lash, the crop is small.
When watermelons reach the size of a tennis ball, a net is put on each of them and tied to the upper trellis. If this is not done, the plant will fall from the added weight. A month after the formation of the ovary - you can harvest.
And one more thing ... The leaves of watermelons are not thinned out, their rugged structure does not obscure the fruits, but the constantly appearing lateral shoots greatly delay the moment of ripening - they are plucked regularly. In addition, watermelon does not like weeds growing at its roots, so it is necessary to monitor the cleanliness of the greenhouse. And, if the fruits were formed at the very base of the lash, you don’t need to tie them up, however, laying them on the ground, you need to put a wooden plank under the watermelons, otherwise there is a high probability of their decay.
Watering and fertilizing watermelon
Despite the popular belief that watermelon loves watering, in fact, this plant is drought-resistant and must be watered very carefully. Most of all, he needs water in the first period of growth - before flowering and at the time of the initial development of the ovaries. It is better to water it with warm water at the rate of 10 liters per 8 - 10 plants. And as soon as the fruits reach the size indicated in the description of the variety, stop watering.
Along with weekly watering, it is good to carry out top dressing. To do this, mix 1 tbsp. a spoonful of azophoska, 1 tbsp. a spoonful of superphosphate, 1 teaspoon of potassium sulfate and 2 teaspoons of any microfertilizer. In total, no more than 4 top dressings are carried out, also until the berry reaches the varietal size.
