Temperature relationship with plant growth is often described in a method called "heat units". Heat unit concept was developed on the basis that the plant every day to collect a number whose magnitude depends therm daily average temperature and base temperature (threshold). Based on this, climate data, especially temperature Grokgak area, Buleleng analyzed to predict the timing of flowering and harvest time possibilities that will be associated with efforts to improve productivity through improved farming patterns. Planting corn planting in the period from July to October showed early flowering period and ripening process occurs at the age of 37 days dan74 days after planting. In this period cook physiology occurs 9 days earlier against the planting period of November - February and five days of the planting period from March to February.