Tangerine trees, which belong to the Mandarin orange family (Citrus reticulata), are popular fruit trees known for their relatively small stature compared to other citrus varieties. The final size of a mature tangerine tree is not fixed; instead, it varies significantly based on genetics and management. Understanding the size categories and the variables that influence growth is paramount for gardeners planning to incorporate these trees into their landscape. This article defines the typical size ranges and explains the biological and environmental controls that determine a tree’s ultimate dimensions.
The Core Answer Mature Dimensions
The mature size of a tangerine tree is categorized into three main groups. A standard, or full-sized, tangerine tree typically reaches a height between 15 and 25 feet when planted in the ground and left unpruned. These full-sized specimens usually develop an equally broad canopy spread.
Semi-dwarf tangerine trees mature to a more manageable height of about 8 to 15 feet tall and wide. This size is often preferred by home gardeners as it allows for easier harvesting and maintenance. The smallest category is the true dwarf tangerine tree, which generally stays within a compact range of 3 to 10 feet tall. This miniature size makes them ideal for small yards or for growing in containers.
The canopy of a tangerine tree tends to be nearly as wide as it is tall, resulting in a rounded, dense form. For example, a semi-dwarf tree reaching 12 feet in height will usually have a canopy that spreads about 12 feet across. Gardeners should plan the required planting area based on both the expected height and the corresponding width.
Factors Influencing Final Size
Rootstock
The most significant factor determining a tangerine tree’s final size is the rootstock onto which the desired tangerine variety, or scion, is grafted. Since nearly all commercial tangerine trees are grafted, the root system dictates the vigor and ultimate size of the plant. Rootstocks like ‘Flying Dragon’ are known as true dwarfing rootstocks because they restrict the movement of growth hormones and nutrients, resulting in a consistently small tree. Other rootstocks, such as rough lemon or sour orange, are more vigorous and lead to a standard-sized tree. Semi-dwarf trees are often created by using a moderately vigorous rootstock like Poncirus trifoliata hybrids. The choice of rootstock has a far greater impact on the tree’s maximum height than any environmental factor.
Environmental Conditions
Environmental conditions also play a secondary role in influencing where a tree falls within its genetic size range. Tangerine trees require at least six to eight hours of direct sunlight daily for optimal growth. Poor soil quality, insufficient drainage, or chronic water stress will result in a smaller, less vigorous tree than its genetic potential suggests.
Cultivar Influence
The specific tangerine cultivar itself has a slight influence on overall size and growth habit. Cultivars like ‘Dancy’ or ‘Sunburst’ are known to be naturally more vigorous and may push the upper limits of the size range, often reaching 12 to 15 feet. Conversely, some varieties naturally exhibit a more compact growth pattern, even when grafted onto the same rootstock.
Techniques for Size Management
Pruning
Gardeners can actively manage the size of their tangerine trees to suit smaller spaces, even if the tree is a standard variety. Pruning is the primary method for size control and should be performed in late winter or early spring before new growth begins. To reduce the tree’s overall height, gardeners can use heading cuts, which involve cutting back a branch to a bud or a smaller side branch. Structural pruning helps maintain a desirable size and shape, but remove no more than one-third of the canopy volume in a single season. Aggressive pruning can encourage sunburn on the newly exposed bark of the main trunk and large branches. Consistent, moderate pruning is more effective for maintaining a smaller, healthier tree over time.
Container Growing
Growing a tangerine tree in a container is a highly effective, non-genetic method to permanently restrict its size. The limited volume of soil and root space physically stunts the tree, keeping it in the dwarf or semi-dwarf size range, regardless of the rootstock used. For a mature, fruit-producing tree, a container size of 15 to 25 gallons is often the sweet spot. While a container-grown tree will never reach the height of its in-ground counterpart, it will still produce full-sized fruit. Regular repotting or root-pruning every few years is necessary to ensure the tree remains healthy and productive.