Growth Explained! - P.S. I don't know why the text is white

From this picture you can see that I added a cactus to encourage the growth of Bud and Spud.Spud listened......but obviously Bud didn't. Spud is growing towards the sun ! This is because of the plant hormone auxin which causes the elongation of cells in shoots and is involved in regulating plant growth. It causes plants to move towards the light because auxin elongates the shaded cells. Cytokinin is what causes the cells to divide. Theses to hormones need to be balanced with each other in order for cells to grow big and tall. Plant growth occurs in areas called meristems, that are the site of repeated cell division of nonspecialized cells. Apical meristems are located in the root and shoot tips of the plants. This is where primary growth occurs with mitosis. Thickening of the stem occurs in the lateral meristems which is required by perennial plants that grow year after year, and need the structural support to continue growing. Secondary growth is what causes the thickening and this occurs in the vascular cambium and cork cambium of the perennial plant. Vascular cambium grows outward in rings that thicken the plant over time. The outermost layer protects against pathogens and this is called the cork cambium.