The guava tree (Psidium guajava) is a small tropical tree valued for its aromatic and flavorful fruit. Fruit production begins with the flowering stage, a key event in the tree’s reproductive cycle. Understanding the timing and triggers of this bloom is important for cultivation, as it determines the abundance and timing of the subsequent harvest.
The Primary Blooming Schedule
In tropical climates, guava trees can bloom and fruit nearly year-round. They do not follow a strict seasonal schedule but flower on new growth flushes that occur periodically, leading to continuous fruit production.
In subtropical regions, cooler winter temperatures concentrate the blooming schedule. The primary flowering period typically occurs in the late spring or early summer, following the cool season. This concentrated bloom is usually the heaviest of the year, resulting in a major fruit crop later in the season.
The flowers are small, approximately one inch (2.5 cm) broad, and white with numerous prominent stamens. They appear singly or in clusters of two or three in the leaf axils of new shoots. The entire blooming period for a given flush can vary from about 25 to 45 days.
Environmental Triggers for Flowering
Flowering initiation is heavily influenced by environmental cues, especially in non-tropical zones. Guava trees require warm conditions, with ideal temperatures ranging from 73° to 82°F (23° to 28°C). Temperatures consistently below 60°F slow or halt the vegetative growth necessary for flowering.
A common trigger for a major bloom flush is a period of water stress or a brief dry spell. Growers often manipulate this by withholding water for two to three weeks, encouraging new shoots to form when irrigation resumes. Since flowers are borne exclusively on new growth, cultural practices like pruning can also stimulate growth flushes and manipulate bloom timing. Full sunlight exposure is also important for efficient flowering and fruit set.
From Flower to Fruit
Once the flowers open, fruit development begins. Guava flowers are primarily self-pollinating, meaning a second tree is not strictly required for fruit set. However, insects like honeybees can assist in cross-pollination to enhance production. Following successful pollination, the petals drop, and the tiny fruit begins to swell.
The time required for the fruit to mature varies based on the cultivar and climate. The initial fruit set period, where small green fruits are established, lasts about 12 to 18 days. Maturation takes between 90 and 150 days from the initial flowering to reach harvestable maturity. Fruit develops better flavor when allowed to ripen fully on the tree, often indicated by the skin changing to yellow. In subtropical areas, fruit from the main spring bloom typically ripens over the late summer and fall.