Climate requirement: Suitable climates for citrus are the tropical and subtropical humid regions of the world. However, the tropical zone is the best region for the cultivation of pomelo. The fruit is said to achieve its highest flesh quality in subtropical humid climates or the drier regions (i.e., Mediterranean climates) with irrigation (Rieger 2002).

Light requirements: Most citrus species require full sunlight to grow well and produce fruit. Shading greatly decreases plant vigor and productivity.

Minimum temperature tolerated: Pomelo strives and produces fruits under optimum temperatures of 23-30ºC with optimum light requirement of 32.3-86.1 klux. The fruit is killed by 30 minutes of temperatures at -3 to -2ºC. Stems and leaves can be killed by a few minutes at (-7 to -3) ºC (Rieger 2002). This is dependent on previous climatic conditions and age of fruit, leaves and branches. Citrus becomes quiescent at temperatures below 13ºC.

Elevation: In the subtropics, citrus grows between sea level and 750 m above sea level. In the tropics, citrus does well below 1600 m. Grows in lowland tropics in elevation up to 400 meters above sea level.

Water requirements: Adequate soil moisture is very important for quality fruit production. Dry conditions can mean smaller fruit, premature fruit drop, and dry and grainy fruit. Consistent, but not too frequent, irrigation may be necessary for optimal health and productivity. Mulching can help keep the soil moist by reducing evaporation of soil moisture. Genarally, pomelo requires sufficient water throughout the year.

Mean annual rainfall 900-3000 mm for normal tree growth and fruit production. Without irrigation, 900 mm per annum is typically needed for any significant fruit production. Optimum and minimum annual rainfall between 1,900-2,400 mm and 1,270 mm, respectively, are required in Malaysia for good pomelo production. However, pomelo can also be planted in wetter areas because pruning and manipulation of fertillizer application for the induction of flowering can be practised, so that the fruit can ripen in accordance with market demand (Mohamad Bahagia A.G et. al., 2008).

Rainfall pattern: Dry season duration (consecutive months with <40 mm rainfall) is 1-3 months. (The dry season in Mediterranean climates where citrus is often grown is up to 4 months.)

Waterlogging: Pomelo does not tolerate waterlogging. When temperatures are over 24ºC, fibrous root death from lack of oxygen (anoxia) can begin within 7-14 days. As roots die, trees develop water stress symptoms such as leaf wilting, yellowing, and drop. How quickly water stress develops depends on water movement, soil pH, and the amount of hydrogen sulfide present. Hot weather will speed up the development of visible symptoms. Moving water delays the development of anoxic symptoms, so it is important to start drainage operations as soon as possible. If drainage reduces water levels 10-15 cm per day, root loss can be avoided. Even circulating water within a block is better than allowing water to stagnate. Hydrogen sulfide (H2S) minerals produced by anaerobic bacteria have an odor of rotten eggs (in acid soils but not in all cases), which is an indication that fibrous roots are dying. This process can be slower at higher soil pH.

Salt: Pomelo does not tolerate salinity well. For this reason, most citrus grows poorly in coastal and atoll environments. High levels of salt in water will increase the osmotic pressure and reduce the ease of water uptake by trees (Boman and Stover 2002)

Wind: Citrus trees are susceptible to leaf, branch, and fruit damage in strong winds.