The giant maidenhair fern complements the North-facing direction as it resonates with Water element prominent there, fostering balance and tranquility. Its serene aura may subtly direct the energy flow, potentially nurturing harmony and prosperity. However, individual interpretations of Feng Shui principles may differ, requiring personal judgement.

The water spangles plant carries a harmony that complements the earthy quality of the North direction. As per Feng Shui, this direction associated with quiet reflection and deep wisdom, resonates with the tranquil nature of the plant. Remember, the interpretation can vary based on individual perception, hence involvement of an expert is always beneficial when assessing Feng Shui compatibility.

Bluebill is perceived by some practitioners as holding alignment with the North quadrant. This could be due to its Blueish blossoms that subtly echo the Water Element, traditionally tied to this direction. Please remember, Feng Shui interpretations vary widely and the actual nature of this connection may differ substantially based on personal perception and belief.

In Feng Shui, the true indigo appears to strike a harmonious balance when placed in the Northwest direction. The Northwest corresponds to the metal element, creating a nurturing cycle involving the plant's inherent wood energy. This soothing connection may optimize the flow of positive Qi. However, the interaction of elements can be diverse and subjective; thus, individual experience may vary.

The shrubby yellowcrest exudes a calming influence, ideal for fostering a sense of tranquility, vital in Feng Shui practice. It is believed to be most harmonious in the South-facing direction, as this orientation is linked to the fire element, resonating well with the plant's yellow blossoms. This positioning should enhance the overall energy flow, though it's subjective to individual interpretation.

In Feng Shui principles, the tung oil tree is believed to harmonize effortlessly with a southern alignment. Its inherent capacity to attract vital energy, or 'chi', makes it an ideal candidate for this orientation. South is governed by the element of fire in Feng Shui, and the tung oil tree's robust nature may well embody the resilient spirit of this element - suggesting a beneficial bonding of components. However, as perception varies, one may experience different resonances.

The chinese Dragon Lily might bring an enlightening energy when placed in Northwest-facing rooms, a direction related to helpful people and travel in Feng Shui. However, as energy is fluid and volatile in nature, the results are individual and may slightly differ based on certain conditions.

Fire pink, or Fire Pink (Silene virginica), is traditionally thought to harmonize exceedingly well with a South-facing direction. The fiery hues that define this plant embody the fire element, which is intrinsically linked with the South direction in Feng Shui philosophy. The placement is said to stimulate positive energy (Chi), however, individual experiences may vary.