The slash pine is considered agreeable in Feng Shui when placed towards the Northwest. The supporting reason could be its resilience and hardiness that matches the Northwest's defining element, metal, symbolising strength and endurance. Remember, perceptions of Feng Shui can vary greatly across different traditions and practitioners.

The christmas-bells harmonizes well with East-facing environments. It brings a particular kind of energy which, informed by Feng Shui principles, may boost the Wood element usually thriving in such directions. However, be reminded that results could vary tremendously due to individual interpretations and applications of Feng Shui.

The sitka spruce is harmonious with Eastern facing placements, reflecting general Feng Shui principles. Known for its strong wood energy, it represents growth and vitality, syncing well with the East's embodiment of renewal and beginnings. Remember, Feng Shui is deeply personal; the sitka spruce's influence might differ based on individual interpretations.

The poorman's orchid personality is often considered vivacious, making it potentially harmonious or discordant depending on other energies present. Aligned with South-facing directions, this plant is seen to promote growth and transformation, harnessing the fire energy of the South. This is typically ideal for those seeking personal advancement or rejuvenation, but subjective outcomes may vary based on personal energies and the plant's overall placement.

The nutmeg and mace, with its unique properties, aligns harmoniously when situated in the Southwest quarter. This is attributed to the grounding energy it possesses, effectively complementing the Earth element associated with Southwest in Feng Shui. However, the complex nature of Feng Shui means the final assessment remains deeply personal.

Indian tobacco is said to bring an ambience of healthy liveliness when placed towards the South. This is due to its association with fire, aiding those who desire to welcome vibrant energy into their lives. However, it's essential to notice that the interpretation varies greatly among different schools of Feng Shui.

The rain lily carries prominent yang energy, favoring growth and rejuvenation. This makes it a suitable entity for the West direction which represents the Metal element, fostering creativity and change. However, the rain lily's compatibility may vary depending on individual circumstances due to the often personalized nature of Feng Shui.

The superb fig is considered moderately auspicious in the Feng Shui domain. Its vibrant, verdant leaves bring life to the interior landscape and subtly rejuvenate the chi. Aligned to the North-facing direction, this plant is ideally positioned to boost career success and personal growth. This compatibility, however, hasn't been universally embraced, varied interpretations within the rich tapestry of Feng Shui wisdom exist.