In Chapter 3 we discussed that plant can assimilate simple molecules (mineral ions, water and CO2) into more complex molecules like proteins, fats and carbohydrates. Rates at which plants assimilate “simple moles” depends for a large extend on their environment. Key environmental factors for plant growth are: §5.1.1 light (quantity and quality), §5.1.2 temperature, §5.1.3 water and nutrients §5.1.4 soil or substrate, §5.1.5 humidity and §5.1.6 carbon dioxide availability. As indicated with the paragraph symbol, each section/paragraph briefly explains the effects of these environmental factors on plant growth.