The variations in ER structure and motility under different stages of cell development remain largely unexplored. Here, I observe ER structure and the changes that take place in this structure over time in growing and non-growing live epidermal cells of the pea tendril. The ER was labelled by green fluorescent protein, fused to the KDEL-ER retention signal and confocal scanning laser microscopy was used to localize the fluorescent signal. I found both the structure and motility of growing cells to be different to non-growing cells. The growing cells had a more open arrangement of the cortical ER, fewer lamellae and showed greater tubular dynamics, while the non-growing cells had a denser arrangement of the cortical ER network, with more lamellae and less tubular dynamics. Furthermore, these differences in the cortical ER structure and dynamics were due to growth as, the ER in non-growing cells showed characteristics similar to those seen in growing cells when these cells were induced to grow by the exogenous application of auxin. These changes in ER structure and dynamics were dependant on both the microtubules and actin cytoskeleton networks.