Tree
Guavas are evergreen, shallow-rooted shrubs or small trees with spreading branches. Trees can grow to a height and spread of 6 to 9 m under high moisture conditions. The trunk is short and freely branching from the base. The bark is smooth, peeling and greenish brown to brown in colour.

Leaves
The leaves are arranged in pairs and oblong or oval in shape. They are smooth on the upper surface and finely hairy underneath. The leaves are between 10-18cm long. Crushed leaves are aromatic.

Flowers
Guava flowers occur singly or in clusters of two to three at the leaf axils of the current or preceding growth. The flowers are bisexual, 3.5cm in diameter, white with four or five petals . The flowers are self-fertile but considerable cross-pollination occurs. The flowers usually open between 5 and 7am depending upon the cultivar and morning temperatures.

Fruit
The fruit varies in size from 2.5 to 10 cm in diameter. The shape can be globose, ovoid, elongated or pear-shaped. The skin colour is yellow when ripe but the flesh can be pink, salmon, white or yellow. The skin texture may be rough or smooth. The seeds are usually numerous, embedded in the pulp, yellowish in colour and 3 to 5 mm long.

The guava is not a long-lived tree (about 40 years), but the plants may bear heavily for 15-25 years. Seedlings may flower within 2 years; clonally propagated trees often begin to bear during the first year after planting. The trees reach full bearing after 5-8 years, depending on growing conditions and spacing.

One important characteristic of guava is that the flowers are borne on newly emerging lateral shoots, regardless of the time of the year. This means that flowering and fruiting can be erratic or perfectly seasonal, depending on how the environment affects shoot growth. This characteristic allows the tree to be manipulated to crop when desired in a favourable tropical climate.

In the tropics the guava tree is found from sea level to an altitude of about 1500 m and can stand temperatures from 15-45°C; optimum mean temperatures being 23-28°C. Guava is more drought-resistant than most tropical fruit crops but it does best with 1000-2000 mm of rain, evenly distributed over the year.

Guava is adapted to a wide variety of soil types. Trees will thrive on shallow, infertile soils, although growth and production will be poor. Optimum soil conditions are those with good drainage and high organic matter , with a pH range of 5 to 7. In soils with pH greater than 7 iron and zinc deficiencies can be a problem.

The guava is native to the American tropics. Spanish explorers took the guava to the Philippines and the Portuguese took it from the Philippines to India. It spread rapidly throughout the tropics and became naturalised to the extent that people in different countries considered the guava to be indigenous to their own region.