Detailed Explanation of Key Technical Points for Continuous Cropping of Watermelon

First, select a plot with few diseases, deep plow and freeze the soil clods before winter, and after spring begins, apply base fertilizer as required and backfill the melon trenches; second, combine garden cleaning with staggered-row sowing, and adopt chemical prevention, focusing on root drenching, supplemented by foliar spraying. Third, do not use the method of burying vines under soil, but use the method of pressing vines on the surface; if necessary, adopt grafting cultivation measures, and for fertilization, it is best to apply organic fertilizer.

(1) Select a plot with few diseases. If in the first year there are no or very few dead seedlings caused by Fusarium wilt in the melon field, it indicates that there is very little Fusarium wilt fungus in that plot. Such land can be used for continuous cropping of watermelon in the second year, but corresponding measures should be taken.

(2) Deep plow and freeze the soil clods before winter. Deep plow the plot intended for continuous cropping of watermelon before winter of the previous year, dig melon trenches according to the row spacing, and carry out freezing of the soil clods. After spring begins, apply base fertilizer as required and backfill the melon trenches. This can both freeze underground pests to death and reduce the occurrence of Fusarium wilt.

(3) Combine garden cleaning with staggered-row sowing. After the watermelon vines are removed in the first year, promptly clean the melon field and remove all residual branches and fallen leaves. The melon rows for continuous cropping should be sown staggered from the previous crop's melon rows, with a staggered distance of 60 cm. In addition, do not casually throw melon vines into the irrigation ditches at the edges of the field, otherwise the pathogens will return to the melon field with the irrigation water.

(4) Adopt chemical prevention. It is not recommended to use bactericidal agents. Because after using fungicides, a sterile environment is formed, and harmful bacteria are more likely to breed than beneficial bacteria, making it very difficult to thoroughly solve the problem of continuous cropping disease in watermelon. The method of use is mainly root drenching, supplemented by foliar spraying.

(5) Do not press melon vines deeply. To reduce the chance of pathogen infection in the melon field, generally do not use the method of burying vines under soil, but use the method of pressing vines on the surface.

(6) Grafting cultivation. If the previous crop of watermelon had severe disease, grafting cultivation measures should be adopted, because after grafting, infection by Fusarium wilt fungus can be avoided or reduced.

(7) Apply organic fertilizer. It can rapidly build soil fertility, supplement organic matter, and inhibit various soil-borne disease pathogens in the soil, reducing the incidence of watermelon disease.