Introduction to soilless cultivation techniques of watermelon

Watermelon is one of the most popular fruits in summer, with a lot of juice and sweet pulp, especially the chilled watermelon juice tastes more refreshing. Watermelon has diuretic, heat-clearing and other effects, now eating watermelon is not limited to summer, generally can be eaten all the year round. The common planting methods of watermelon are planting in open field and greenhouse, so can they be cultivated without soil? What are the technical points?

1. Methods for soilless cultivation

The commonly used method of soilless cultivation of watermelon is sand and gravel planting water culture, that is, planting in the cultivation pond, using sand and gravel as the planting substrate, and providing it with nutrient solution at a specified time.

2. Selection of matrix and disinfection measures.

The substrates commonly used in soilless cultivation of watermelon are bark, shavings, bagasse, rice husk and so on. It can be used alone or in combination. Specifically, it should be adjusted according to the specific conditions of the planting area.

The substrate must be disinfected, and if no variety of fruits or vegetables have been planted in the area, the selected fresh substrate does not have to be sterilized.

In the case of long sunshine in April and May, you can appropriately increase the use of ammonium nitrogen, so that watermelons will fade to green or yellow when they lack nitrogen or iron. If there is no nitrogen, there will be relatively small shape, yellowing color, abnormal development of the whole plant. If there is a lack of iron, it will show yellowing between the veins.

The commonly used methods of matrix disinfection are solar energy disinfection and steam disinfection.

Solar disinfection is to pile up the matrix to a certain height in the hot summer, spray water on the substrate so that its water content exceeds 80%, then cover it with plastic film, seal it in the greenhouse and expose it to the sun for half a month. Better disinfection effect can be achieved. Generally, the sterilized matrix is filled into the culture bed a week before culture, with a thickness of about ten centimeters.

Steam disinfection is mainly to achieve the effect of sterilization, the matrix can be put in the sterilization room for disinfection, the specific length and width should be determined according to the terrain and quantity of planting. The effect of this kind of disinfection is very good, but the cost is relatively high.

3. Planting essentials

In different growth periods of watermelon, the supply of nutrient solution needs to be adjusted according to its growth, season and so on. For example, it is necessary to increase the composition of phosphorus and potassium appropriately in the result period.

No matter which kind of soilless cultivation method, the nutrient solution is directly related to the root growth and mineral nutrition absorption of watermelon. The phenomenon of low temperature is easy to occur in soilless cultivation in spring greenhouse, so the nutrient solution should be heated at this time.

Soilless cultivation of watermelons, then the lack of carbon dioxide will seriously affect the growth of watermelons, so it is necessary to apply carbon dioxide fertilizer. Common methods include ventilation, composting and fermentation, the use of dry ice or compressed carbon dioxide, and the use of gas generators to supplement carbon dioxide.