Avocados are botanically classified as a large berry and undergo a remarkable transformation from a tiny flower to the familiar fruit found in stores. Tracing the avocado’s development from the structure of the mature tree through the flowering process and subsequent stages of fruit growth reveals a unique agricultural spectacle. This visual progression is characterized by subtle shifts in appearance, size, and texture that ultimately signal the moment of harvest.
The Mature Tree and Foliage
The established avocado tree presents as a substantial, evergreen structure, ranging from shrubby cultivars to towering specimens that can reach heights of 40 to 80 feet. The bark on older trees is typically rough and grayish-brown, supporting a dense canopy that provides significant shade. The overall shape of the crown can vary widely among varieties, from the columnar form of ‘Reed’ to the more rounded, umbrella-like shape of ‘Hass’.
The leaves are simple, broad, and leathery, displaying a glossy, dark green hue on their upper surface. These leaves are typically elliptic or oval and can measure between four and eleven inches long. New vegetative growth, which emerges in flushes throughout the year, often appears as a striking reddish or bronze color before hardening off to the mature deep green. This continuous presence of foliage, rather than seasonal shedding, defines the tree’s appearance outside of its reproductive cycles.
The Characteristics of Avocado Flowers
The reproductive phase begins with the appearance of thousands of small, non-showy flowers. These blossoms emerge in large, branched clusters called panicles, typically located at the tips of the branches. Each individual flower is inconspicuous, measuring only about one-quarter to three-eighths of an inch across.
Their color is generally a pale, yellowish-green, which often makes them blend into the foliage. The flowers possess both male and female structures, but they operate on a unique, two-day cycle known as synchronous dichogamy. Because the flowers on a single tree are functionally female during one opening and male during a second, they are present in massive numbers to maximize cross-pollination.
Early Fruit Set and Development
After successful pollination, only a tiny fraction of the numerous flowers will transition into developing fruit. The initial fruit set is visually represented by tiny, hard, green spheres, often described as “pinhead” or “pea-sized” fruitlets. These miniature avocados are attached to the remnants of the flower structure and are initially clustered tightly together within the panicle.
As the small fruitlets begin to grow, they swell to the size of marbles and then golf balls, maintaining their smooth, bright green skin. During this period, the tree undergoes a natural, dramatic drop of excess fruit, a process known as natural thinning. The fruits that survive this critical period slowly begin to elongate, taking on the characteristic pear or oval shape of the mature avocado.
This stage of slow, hard, green growth can last for months, with the fruit remaining firm and seemingly unchanging as the tree prioritizes resource allocation.
Visual Cues of Maturation and Harvest Readiness
The final stage of development sees the fruit reach its full, mature size on the tree, often growing large enough to pull the supporting branch into a noticeable downward curve. A key distinction of the avocado is that it does not ripen—meaning it does not soften or significantly change color—while it remains attached to the branch. The fruit must be picked while still hard and firm.
Visual indicators of harvest readiness are subtle and vary by cultivar. For ‘Hass,’ the skin begins as bright green and becomes noticeably duller and slightly rougher or waxy as it matures. Some varieties, like ‘Hass,’ will exhibit a slight darkening toward a purplish-black hue while still on the tree.
Many other varieties, such as ‘Fuerte’ and ‘Reed,’ remain a deep green color even when fully mature. Growers rely on the loss of glossiness, the specific size, and the time of year rather than a dramatic color change to determine when the hard, full-sized fruit is ready to be clipped.