To provide an epoch-making support holder so designed as to firmly install a support 6 on a container 1 such as a planter, easily regulate the standing position of the support 6, and also reinforce strength of the container itself.

The support holder has the following structures: flexibly sliding engagement parts 4 are provided respectively at both end parts of a bridging body 3 set between facing edge parts 2A, 2B of the upper opening edge 2 of the container 1 such as a planter for growing plants so as to be fitted to the facing edge parts 2A, 2B and flexibly move slidingly along the facing edge parts 2A, 2B in the fitted condition as they are so that the bridging body 3 is bridged between the facing edge parts 2A, 2B of the upper opening edge 2 of the container 1; and the bridging body 3 is provided with insertion holes 5 through which the support 6 is passed to be installed so that the support 6 installed on the soil charged in the container 1 is passed through the insertion hole 5 of the bridging body 3 set between the facing edge parts 2A, 2B of the upper opening edge 2 of the container 1 to be installed so that the support 6 is held in a fall-down preventive condition.