Plant internodes are the portions of the stem between two successive nodes. Nodes are the points on the stem where leaves, branches, buds or aerial roots can grow. Internodes help in transporting water, hormones and food from node to node and also in increasing the height of the plant. The length of the internodes can vary depending on the species of plant and the environmental conditions. Some plants have short internodes and dense foliage, while others have long internodes and sparse leaves.