The Bird of Paradise plant (Strelitzia) is widely sought after for its striking, architectural foliage and distinctive flowers that resemble a tropical bird in flight. Its visual appeal makes it a popular choice for indoor houseplant enthusiasts and outdoor landscapers in warmer climates. The final size is heavily influenced by the specific species chosen and the surrounding growing environment. Understanding the genetic potential between the most common varieties is key to managing expectations for its eventual height.
Defining Maximum Height by Species
The size a Bird of Paradise plant reaches is primarily determined by its species. The two most commonly grown types are the Orange Bird of Paradise (Strelitzia reginae) and the Giant White Bird of Paradise (Strelitzia nicolai). These two species differ dramatically in their potential mature size and growth habit.
The Orange Bird of Paradise (S. reginae) is the smaller, shrub-like variety. It typically reaches a maximum height of three to five feet outdoors, maintaining a moderate spread of about two to four feet and forming dense, manageable clumps. Its compact size makes it the preferred choice for container growing and smaller garden spaces.
In contrast, the Giant White Bird of Paradise (S. nicolai) is a massive, tree-like perennial that requires significant space. Under ideal outdoor conditions, this species can reach heights between 18 and 30 feet, with some records listing heights up to 33 feet. Its spread can also be substantial, reaching up to 10 to 20 feet wide, forming large, woody clumps.
Environmental Factors that Limit Growth
While the species determines the potential maximum height, environmental factors often prevent the plant from reaching its full potential, especially when grown outside of its native subtropical range. The most significant limiting factor is light availability, as the Bird of Paradise requires high light levels to fuel vigorous growth. Plants grown in full sun outdoors will be smaller and more floriferous, while those in partial shade may stretch taller but produce fewer blooms.
Temperature is another major constraint, as the plant is cold-sensitive and cannot withstand prolonged frost. In regions with cold winters, the plant must be grown in a container and moved indoors. This inherently restricts its size due to the limited growing season and cooler ambient temperatures. Indoor environments provide lower light intensity, contributing to a slower growth rate and smaller overall stature.
The moisture and nutrient content of the soil also play a role in size, as these tropical plants prefer fertile, well-drained soil. Consistent watering during the warm growing season promotes the robust root system necessary for maximum height. Nutrient deficiencies lead to stunted growth, while regular fertilization supports the plant’s moderate to slow growth rate.
Strategies for Managing Plant Size
Gardeners can influence the final size of their Bird of Paradise, especially when growing indoors. The most effective method for restricting growth is to intentionally keep the plant pot-bound. Allowing the dense, fleshy roots to fill the container signals the plant to slow its vegetative growth, keeping it much smaller than its genetic maximum.
Repotting is recommended only every one to two years, and only into a container marginally larger than the previous one. If the goal is to maintain the plant’s current height, refresh the soil and prune some of the root mass before returning the plant to the same container. This process keeps the plant root-constrained, which also encourages more reliable flowering.
Pruning is primarily used for maintenance rather than size reduction, as the plant is a clumping perennial. Removing dead, yellowed, or damaged leaves at the base of the stem improves the plant’s appearance and air circulation. To reduce the overall clump size, more aggressive pruning involves dividing the plant by separating the rooted offshoots using a sharp tool to manage the spread.