The polynesian metrosideros is seen as compatible with the South direction, believed to carry Yang energy and fire elements. As a vigorous growing plant, it echoes the South's liveliness and vitality in Feng Shui, stimulating ideal energy flow and promoting prosperity. However, this suggested positioning should be flexibly interpreted given the nuanced nature of Feng Shui.

The miniature fishtail palm exudes a metallic sheen that may attract prosperity when placed in the West, a sector associated with metal element in Feng Shui. However, the true harmony of energy flow and the plant's effect depend on your intuition and discernment. Its compatibility should be examined within the context of your personal space.

The nettle-leaved bellflower carries subtle Yin energy, resembling a murmur of tranquility. While its compatibility with each living space may vary, its alignment is often perceived as most harmonious with a West-facing direction. This kind of arrangement invites an amplification of tranquility in your space, an attribute presumably associated with the nettle-leaved bellflower's gentle nature. Please note, the experience may differ personally, affirming the subjective nature of Feng Shui.

The calanthe orchid is perceived to have a harmonic resonance when placed in the Southwest. The plant's intricate blooms and even-formed leaves match the Earth elements dominant in this direction, imparting balance and fostering prosperity in Feng Shui theory. However, practitioners should feel the energy themselves due to Feng Shui's subjective nature.

The apple-ring acacia displays potential compatibility with west-facing spaces. According to Feng Shui canon, west embodies Metal elements. These areas are typically linked with children, creativity, and future prospects. The apple-ring acacia's properties correlate with these aspects, facilitating a balanced and hearty ambiance. Nevertheless, do bear in mind results could vary since Feng Shui is a matter of personal interaction with one's environment.

As a prolific grower, the air potato signifies abundance and growth in Feng Shui, particularly compatible when placed in the Southwest of the space. The round shapes of its bulbils echo the element of Earth, which dominates the Southwest, promoting stability and nourishment. Remember, each plant's impact can be different based on individual interpretations and settings.

The spotted knapweed can be a paradoxical addition to a Feng Shui setup, maneuvering the balance of chi in unusual ways. When placed in the West direction, the plant's vibrant spots tend to resonate with the Metal element prevalently dominant in this quadrant. However, being an invasive species, it may stimulate disruptive chi flow. A word of discretion for Feng Shui enthusiasts - the harmony a spotted knapweed adds is as eccentric as the plant itself and may not consistently align with traditional practices.

The ivy-leaved speedwell tends to harmonize well with a Northeast facing direction. This suitability is grounded in its modest needs for sunlight and its resilience, mirroring the Earth energy associated with the northeast in Feng Shui. However, these observations should be considered alongside other personal and environmental factors for optimal Feng Shui.