Automation is need of future and automation in farming is necessary as there is acute storage of fertile land and skilled farmer. Understanding the stages of plant growth is important to help farmers to optimize the yield. Vegetables and fruits are most important agricultural products. In order to obtain more value added products, a proper quality control is essentially required. Many studies show that quality of agricultural products may be reduced from many causes. One of the most important factor of such quality is plant diseases. This paper provides advances in various methods used to study plant growth and diseases using image processing.