Wisteria, a distinctive vine plant known for its climbing ability, can grow to significant heights and is often used for creating hedges. Among its various species, Wisteria frutescens and Wisteria macrostachya stand out, with ‘Amethyst Falls’ and ‘Blue Moon’ being their most notable varieties. Today’s discussion centers on these two.
The primary distinction between ‘Amethyst Falls’ and ‘Blue Moon’ lies in their blossoms. ‘Blue Moon’ Wisteria features larger inflorescences, characterized by a subtle bluish hue. In contrast, ‘Amethyst Falls’ Wisteria boasts more compact clusters of flowers, distinguished by their rich purple color.
Their color is different
‘Amethyst Falls’ is known for its violet blossoms, which can vary in intensity. Depending on the growing conditions, the flowers may present a deep purple hue but will never achieve a true blue color.
In contrast, ‘Blue Moon’ truly embodies its name with distinctly blue flowers. The shades may range from lighter to darker blue, and occasionally, the blooms might exhibit a slight purple hue, though not as pronounced as in ‘Amethyst Falls’.
For both varieties to flourish with vibrant blooms and rich colors, ample direct sunlight is crucial. Ensure they are positioned to receive at least 6 hours of sun daily, regardless of your hardiness zone.
Blue Moon is more hardy
Both ‘Amethyst Falls’ and ‘Blue Moon’ varieties of wisteria bloom on new wood, making them resilient to harsh winter frosts. Their flower buds develop in spring, enabling them to withstand winter conditions better than Asian wisterias.
‘Amethyst Falls’ is known for its early blooming period, starting in May. However, in hardiness zone 4, this timing can coincide with severe frosts, potentially harming the young buds. Therefore, it’s advisable to cultivate ‘Amethyst Falls’ in zones 5 to 9 for optimal growth.
Conversely, ‘Blue Moon’ is a variety that flowers later, typically starting in June, which can vary from early to mid-month. This later blooming period offers an advantage in zone 4, as the risk of late frost damage is minimized.
Consequently, ‘Blue Moon’s late flowering trait makes it better suited for colder climates, extending its accessibility to a wider range of gardeners.
Amethyst Falls is less fragrant
For gardeners who prioritize fragrance in their plants, ‘Amethyst Falls’ may not meet expectations, as its scent is quite faint. In a large garden or from a distance, it’s unlikely that you’ll notice its aroma.
Conversely, ‘Blue Moon’ boasts a strong fragrance that permeates the garden when in bloom. Opinions on the scent vary, with some describing it as sweet, but one thing is certain: ‘Blue Moon’ offers the dual pleasure of both visual beauty and a delightful aroma.
Blue Moon blooms three times a season
‘Amethyst Falls’ typically has its initial bloom in early spring, with the possibility of a second bloom in late summer. However, this second bloom isn’t guaranteed, and in some cases, it may not occur at all.
In contrast, ‘Blue Moon’ starts blooming in early summer, followed by a second bloom in mid-summer, and often a third flowering in August. While the third bloom isn’t a certainty and may vary from year to year, ‘Blue Moon’ generally exhibits more frequent reblooming compared to ‘Amethyst Falls’.
It’s important to note that for both varieties, the subsequent blooms are usually not as abundant as the first. This is because the plant expends a significant amount of energy on the initial flowering, leaving it with less vigor for subsequent blooms.
Therefore, ‘Blue Moon’ tends to outshine ‘Amethyst Falls’ in terms of offering a longer period of floral display and fragrance, making it a more appealing choice for those seeking extended enjoyment from their wisteria blooms.
Blue Moon has larger inflorescences
The inflorescences of ‘Blue Moon’ Wisteria are notably lush and rich, resembling grape bunches. This effect is due to the racemes comprising 60-70 flowers each. Additionally, these racemes are about 12 inches long, creating impressive cascades of blue flowers.
In contrast, ‘Amethyst Falls’ presents a different picture. Its inflorescences typically contain around 30-45 flowers, with an average length of about 7 inches. Consequently, the overall appearance of ‘Amethyst Falls’ is less spectacular compared to ‘Blue Moon’.
Amethyst Falls has more leaves
The key distinction between these two wisterias lies in their foliage. Wisteria leaves are typically arranged in a unique pattern along long, drooping branches. ‘Amethyst Falls’ features 11-15 leaves per branch, whereas ‘Blue Moon’ typically has 7-11 leaves per branch, resulting in a less dense foliage cover.
While wisterias are primarily prized for their spectacular blooms, with foliage often being a secondary consideration, this difference in leaf density is significant for certain uses. For instance, if you’re looking to use wisteria as a privacy screen, ‘Amethyst Falls’ would be the preferable choice due to its denser foliage, offering better coverage for privacy compared to ‘Blue Moon’.
The ‘Blue Moon’ variety is part of the Wisteria macrostachya species, commonly found in the United States and often referred to as Kentucky wisteria. On the other hand, ‘Amethyst Falls’ is a variety of Wisteria frutescens, known colloquially as American wisteria. This species is prevalent in North America, especially in states like Virginia, Michigan, and New York.
Both these varieties find their primary competition in Japanese and Chinese wisterias. Asian wisterias are renowned for their more abundant flowering but are less favored for their lower frost resistance, a significant factor in many regions.