Rosemary grevillea is reasonably harmonious with Southwest-facing environments. Per Feng Shui principles, the plant's evergreen nature symbolizes continuous growth and prosperity, strongly resonating with the Earth element of the Southwest. However, individual experiences may vary due to the flexible meaning of Feng Shui.

The crown imperial is often correlated with the concept of imperial authority in Feng Shui, reflecting strong energy. However, it's an intriguing subject, and its compatibility may differ based on individual interpretation. When placed facing South, it may infuse prosperity, as South signifies fame and recognition in Feng Shui. Yet, its bold appearance might also unsettling for some, thus creating a delicate balance.

Sulphur cinquefoil might add to the tranquil energy of a Southwest-facing area. The plant's sturdy stems subtly channel the Earth element, animating the nurturing aspects governed by this direction. However, as with all Feng Shui evaluations, individual perceptions and interpretations can vary.

Rockspray cotoneaster aligns harmoniously with western-oriented spaces due to its horizontal growth pattern which mirrors the setting sun's trajectory. This enhances positive energy flow, creating a serene atmosphere, though interpretation varies.

The mysore trumpetvine has a nostalgic feeling, conveying a subtle but deep sense of tranquility, associated with the element of Wood. Its compatibility with the East is strong, as this direction symbolizes family and health in Feng Shui, and is anchored by the Wood element. This plant embodies a harmonious fusion of the two, minding the subtly of Feng Shui notions.

The roundleaf greenbrier resonates positively in Feng Shui due to its luscious green aura, symbolizing growth and revitalization. Ideally suited for the Northwest facing direction, it's believed to harness the metal energy prevalent in this sector, promoting a sense of calmness and tranquility. However, individual experiences may vary due to the dynamic nature of Feng Shui.

The trumpet honeysuckle can harmoniously influence the flow of positive energy when placed in the North. The North is associated with water element and in Feng Shui, the vibrant colors of trumpet honeysuckle are believed to attract and regulate the water energy promising career advancement and luck.

The dawn redwood is esteemed for its robust vitality. It scales new heights, syncing harmoniously with Southern facings, arguably due to the plant’s association with relentless growth, similar to the symbolisms of the South direction. However, this is open-ended in Feng Shui, highlighting the myriad interpretations and personal connections.