The utility model relates to a half grudging post density of open country watermelon cultivation strutting arrangement, a serial communication port, include: the base, the airtight support that constitutes by at least three bodies of rod that are located coplanar end to end in proper order, the pole setting, graphic settings and its bottom at perpendicular to base place are connected fixedly with the base, at least one bury the pole, the graphic settings at perpendicular to base place and its top are connected with the base and are fixed, two at least connecting pieces, the even setting the pole setting top outside, the utility model discloses can realize the three -dimensional cultivation of the small -size watermelon of open country, have soil and space utilization height, big, the light advantage of plant diseases and insect pests emergence of plant population, effectively improve the plant population of small -size watermelon, enlarge tendril leaf area, improve photosynthetic efficiency, reduce the incidence of small -size watermelon plant diseases and insect pests to the increasing yield and income of the small -size watermelon of open country has been realized.