All three cultivars—'August Beauty', 'Mystery', and 'Veitchii'—belong to the same species, Gardenia jasminoides, an evergreen shrub within the Rubiaceae family. They share the quintessential gardenia traits: glossy, deep green leaves, intensely fragrant, creamy-white flowers, and a preference for acidic, well-drained soil and warm, humid climates. Their primary differences lie in their growth habits, flowering patterns, and specific morphological features, which are a result of selective cultivation for particular garden uses and visual effects.
The growth habit is a primary differentiator. 'August Beauty' is a robust, moderately fast-growing shrub that can reach 4 to 6 feet in height and width, forming a dense, rounded mound. 'Mystery' is arguably the most vigorous of the three, often growing into a large, upright, and almost tree-like form, frequently reaching 6 to 8 feet tall and wide if left unpruned. In contrast, 'Veitchii' is a dwarf, compact cultivar with a very slow growth rate. It typically matures at a petite 2 to 3 feet in height and spread, making it an excellent choice for containers, low borders, or small garden spaces.
While all produce double-flowered blooms, the specifics of their flowering cycles and flower size vary. 'August Beauty' is named for its reliable and prolific blooming season, which peaks from late spring through early fall (hence "August"), often producing waves of flowers. Its blooms are typically 2 to 3 inches in diameter. 'Mystery' is renowned for its exceptionally large flowers, which can reach 4 to 5 inches across. It is a heavy bloomer, primarily in late spring and early summer, with sporadic repeat blooming possible later in the season. 'Veitchii' produces a profusion of smaller, 1.5 to 2-inch flowers. Its key floral advantage is its remarkable longevity of bloom; it is one of the first gardenias to flower in spring and often continues to produce blooms intermittently until frost.
There are subtle differences in foliage and environmental tolerance. Both 'August Beauty' and 'Mystery' have large, broad, deep green leaves that complement their substantial presence. 'Veitchii' has smaller, narrower leaves consistent with its overall dwarf habit. Regarding cold tolerance, 'August Beauty' and 'Mystery' are generally hardy to USDA zones 8-11, sometimes with protection in zone 7. 'Veitchii' is often noted for having slightly better cold resistance than many other cultivars, also thriving in zones 8-11 but potentially being more resilient to occasional colder snaps due to its compact size, which can be more easily protected.
