The vibrant red angel's trumpet harmonizes with the South, embodying the element of Fire with its intense red hue, which promotes reputation and recognition. However, bearing in mind its vigorous growing nature, it's advisable to maintain balance to avoid 'overheated' energy, thus keeping the Feng Shui elements in harmony.

Wild Indigo holds a special energy, exhibiting a balance of yin and yang, thus symbolizing a harmonious integration of opposites. The plant is moderately compatible with the North-facing direction. The reason for this is its association with the element of water, which, according to Feng Shui fundamentals, serves as an elemental base for the North direction. Yet, it remains a personal interpretation, delicately mindful of the individual's uniqueness in their Feng Shui journey.

The water chestnut aligns well with the principles of Feng Shui, associated with aspects of life abundant in change and instinct. Its placement may significantly contribute to positivity and harmony in a dwelling. Placed in the Southwest direction, it could potentially bolster circumstances linked to relationships and femininity. This connection is attributed to the Earth element, which is strongly associated with the Southwest. Remember, perceptions of Feng Shui can vary widely, ensuring this perspective is among several brought to bear.

In Feng Shui, certain plants like pauper's-tea can subtly enhance the vibrancy of a space. Particularly when positioned to the East, it may encourage growth and renewal, given East's affiliation with the wood element. This is a generalized interpretation and specific results may vary.

Suryeon meshes well with the principles of Feng Shui. As this plant symbolizes growth and new beginnings, it reportedly brings positivity and peace. With its affinity for the Northwest direction - traditionally tied to travel and helpful people in Feng Shui - suryeon may instigate beneficial influences and foster serendipitous connections. However, individual interpretations may differ, reflecting the inherently subjective practice of Feng Shui.

Pullback is said to bring balance to one's life when positioned towards the East. From a Feng Shui perspective, this plant encourages spiritual growth and enhances the auspicious energy of the dawn, stimulating wellness and positive vibrations. However, as Feng Shui impacts vary depending on personal circumstances, this interpretation might not resonate with all.

The crimson Columbine resonates with the vibrations of resilience and passion, which aligns well with the fiery nature of South-facing locations. It is suggested that the plant's robust vitality enhances the yang element intrinsic in the South. Keep in mind, differing views may exist due to Feng Shui's individualistic nature.

Prairie Smoke and Feng Shui have an intriguing relationship. Its unique tridentate flowers, often considered a symbol of dynamic energy, could potentially resonate harmoniously with a South-facing direction. South in Feng Shui represents fame and reputation and the plant's triple blossoms might hint at an amplified vitality in line with these attributes. However, due to the art’s vast complexities, results may vary across specific placements and individuals.