Three critical aspects of a description of bacterial growth are colony, size, color, and shape. At least three other important factors--not physical descriptions--typically are included when describing bacterial growth. What do you suppose they are and why are they important?
One of the factors that is always critical to the growth of a bacterial colony is the availability of nutrients, or the type of medium that is used to supply nutrients to the developing bacteria. Without a medium, the bacteria suffer; in extreme cases, the entire colony has the potential to be wiped out. Another factor, secondly, would probably be the temperature of the incubation chamber. Bacteria have a temperature range which is optimum for maximum bacterial growth, so temperature too high or low can have a retardant effect on the amount of bacteria that are produced. Finally, the physical state of the environment the bacteria are growing in would be of prime consideration. Most bacteria excel in moist, wet environments. So the availability of moisture or the lack of it can be a major contributory factor in terms of bacterial growth.