commercial applications of photosynthesis 4.1.2

• horticulture is cultivating plants in gardens for food, medicine or ornamental reasons
• polytunnels are long plastic greenhouses used to grow tomatoes
• plants grow faster in polytunnels because the environment is easier to control and it is warmer inside than out
• to ensure light intensity is not limiting, use artificial lighting at night and during the winter
• to ensure that temperature is not limiting, use a thermostatically controlled heater (to stop it getting cold) or air conditioning (to stop it getting hot
• to ensure minerals is not a limiting factor, add minerals to the water supply or add fertilisers
• to ensure carbon dioxide concentration is not a limiting factor, burn paraffin which releases carbon dioxide and also heat
• the advantages of growing crops in an artificial environment is it is easier to keep plants free from pest and disease, they can grow much faster and produce more decent crops which can be harvested more often to meet consumer demand
• however growing crops in an artificial environment can be very expensive
• greenhouse farming entails farming under a cover and focuses on maintaining sunlight and temperature differences but hydroponics is used to ensure that plants get enough water and focuses less on sunlight and temperature