The question of whether a Foxtail Fern and an Asparagus Fern are the same is a common point of confusion, stemming from their similar appearances and shared lineage. From a botanical perspective, they are distinct plants with clear differences, though they are closely related members of the same genus.
Both the Foxtail Fern and the commonly named Asparagus Fern belong to the genus Asparagus within the family Asparagaceae. It is crucial to understand that the term "Asparagus Fern" is not a precise botanical name but a common name applied to several different species within the genus. This is the primary source of confusion. They are not true ferns at all, as they reproduce by seeds, not spores. Their fern-like appearance comes from their modified, leaf-like structures called cladodes.
The most significant difference lies in their growth habit and the arrangement of their cladodes.
The Foxtail Fern (Asparagus densiflorus 'Myersii') is characterized by its distinctive, symmetrical, and upright growth. Its stems are densely packed with bright green, needle-like cladodes that radiate uniformly around the stem, creating a cylindrical, plume-like, or "foxtail" appearance. The overall structure is very tidy and sculptural.
In contrast, the plant most often called Asparagus Fern is typically Asparagus aethiopicus (formerly Asparagus densiflorus 'Sprengeri'). Its growth habit is entirely different. It is a sprawling or cascading plant with long, arching, or trailing stems. The cladodes are arranged along the stems in a more irregular and loose fashion, often in clusters, but without the dense, radial symmetry of the Foxtail Fern.
These morphological differences lead to distinct uses in landscaping and horticulture. The upright and architectural form of the Foxtail Fern makes it ideal as a focal point in container gardens, as a border plant, or in formal garden settings where structure is desired. The trailing habit of the Sprenger's Asparagus Fern makes it a classic choice for hanging baskets, where its long, cascading stems can be shown to full effect, or as a ground cover in suitable climates.
Both plants develop a robust system of tuberous roots that store water and nutrients, making them exceptionally drought-tolerant. However, this characteristic also contributes to the invasive potential of Asparagus aethiopicus (Sprenger's Asparagus Fern) in warm, frost-free climates like parts of Florida, Texas, and Australia. It can spread aggressively via its tubers and seeds, naturalizing and outcompeting native vegetation. The Foxtail Fern (Asparagus densiflorus 'Myersii') is generally considered less invasive and more well-behaved in the garden.
