Pattern dynamics in a weakly nonlinear regime near the onset of the electrohydrodynamic instability (EHDI) is experimentally investigated in the homeotropic alignment of nematic liquid crystals, of which morphology is introduced. The wavy, chain and bamboo-chevron patterns are observed in homeotropic samples as new patterns. The Busse balloon is also obtained which is quite different from the conventional balloons in EHDI in planar liquid crystals.