Sugarcane is a tropical plant. It grows well in that region where the climate is more or less tropical but it can grow in subtropical too as in north India. Under warm humid conditions, it can continue its growth unless terminated by flower. An average mean temperature of 28-37 ºC is best suited for its growth. Lower temperature reduces tillering. Temperature above 50 ˚C arrest its growth, those below 20 ˚C slow it down. The crop does well in tropical region receiving rainfall of 75-120 cm/annum. Sugarcane requires a long growing season from 10 - 12 months because certain number of heat units is required to bring the plant to maturity. The ideal climate for sugarcane is in the southern parts of country such as Maharashtra, parts of Karnataka and the Telegana areas of Andhra Pradesh. Besides temperature, rainfall and humidity, light plays a very important role in proper growth and development of cane. Under bright sunlight conditions the stems are thicker but shorter and leaves are broader and greener, while under low temperature, the stem are slender and long with narrower and yellowish leaves. Day length also determine flowering in cane. Thus climate plays a very important role in yield of sugarcane.

Climatic requirement at different growth stages
1) Germination

Germination will be quicker at 85-90 ˚F temperatures. If temperature is reduced to 40 ˚F, there will not be enlargement of eye buds, while at 50 ˚F temperatures; it takes about 60-90 days for germination.

2) Vegetative growth phase

Long warm summer with adequate supply of water favours for more tillering and development of long internodes. If there is a water stress, the length of the internodes is reducing.

3) Reproductive phase

It requires low temperature during night and bright sunshine during daytime.

4) Maturity phase

Normally dry climate and cool weather is required but free from frost. It needs cool and dry season.

5) Light

Light is also the most important factor for tillering in sugarcane. Both light intensity and photoperiod influences the tillering. If duration and intensity decreases, the number of tillering also decreases. Sugarcane is considered as sun loving plant. In full sunlight, the plants are healthier, stalks are thicker and leaves are broader and greener. Day length also determine flowering in cane.

6) Temperature

Temperature affect the root growth and root activity is maximum at 80 ˚F and maximum absorption of plant nutrients. At 70 ˚F the absorption is reduced, while at 45 ˚F, uptake of nitrogen is reduced by half and P2O5 by one third.