People often get confused between these two plants. They're both lush and have thick, attractive foliage. The main difference will be in mature size—Aglaonema is a maximum of one or two feet tall, while Dieffenbachia can get much larger. Aglaonema leaves are bolder and have more random leaf variegations. Dieffenbachia at the same time, have a lighter shade inside and a darker shade outside.