What is the effect of light and water on plant growth (I am using grass seed)?
The rate at which grass grows can depend on many, many things. Mineral nutrients, daylength, aeration of the soil, pests, diseases, variety, time of planting, physical features of the soil, presence of other plants within a metre or so, carbon dioxide in the air, as well as water and light. In principle, ONE of these factors will be in the shortest supply and therefore be the one that is limiting growth. You need to look up the chapter on “Photosynthesis” in your text book and perhaps dip into an A level text book. A good text book will talk about “limiting factors of photosynthesis” and illustrate it with a graph of Yield (which might be ‘mass of plants’, or ‘rate of photosynthesis’ or ‘amount of oxygen evolved’ by the plant) up the vertical axis and the factor being investigated along the horizontal axis (this might be ‘light’ or it might be ‘concentration of CO2’). The graph in each case is a curve which rises steeply to start with and then levels off at a maximum yield. (It would b
