Rocky mountain blazing star (Liatris ligulistylis) is a type of aster found in the central United States and Canada. It sprouts large leaves near the ground and smaller ones higher up. A single stalk may produce as many as 21 flowers at a time. Rocky mountain blazing star’s complex flowers are frequented by monarch butterflies and bleeding flower moths.
I. Appearance and Characteristics
Liatris ligulistylis (Rocky Mountain blazing star, northern plains blazing star, or meadow blazing star) is a flowering plant of the family Asteraceae, native to the central United States and central Canada.
The leaves have whitish midribs, and are positioned basally and mostly alternately on the stem. They vary from linear and sessile nearer the top of the plant, to balance with petioles nearer the bottom. The stem is up to 100 cm (39 in). The stem and leaves are sparsely to densely covered with short white hairs.
There are 4–21 flowers arranged in a loose raceme on the upper part of the stem, with rounded pinkish purple flower heads on 8–15 mm (5⁄16–9⁄16 in) stems. Each flower head has 30-100 five-lobed, tubular flowers surrounded by spoon-shaped bracts (phyllaries) with translucent, jagged, and often purple edges that fold inward. Each flower has a long, thread-like, divided style protruding from the center. The fruits (cypselae) are 5–7 mm (3⁄16–1⁄4 in) long, each with a ring (pappus) of barbed hairs at the top.
Liatris aspera is similar to Liatris ligulistylis in having button-like flower heads, but the stalks of its flower heads are shorter or absent altogether, and it prefers drier habitats.
The flowers are popular with monarch butterflies, and it is a host for the bleeding flower moth (Schinia sanguinea).
II. How to Grow and Care
Rocky mountain blazing star thrives in well-drained soils and prefers full sun exposure for optimal blooming. Overwatering should be avoided to prevent root rot, and rocky mountain blazing star typically does not require fertilization due to its tolerance for low-nutrient soils. Special care should be taken to ensure good air circulation around rocky mountain blazing star to discourage disease.
Sunlight
The rocky mountain blazing star will grow in full sun and partial shade. It is most commonly grown in full sun, which encourages full growth, though most will also grow under a little shade. However, too much shade may prevent blooming and can also lead to disease. The rocky mountain blazing star will survive and thrive in bright sunlight and hot summers, with at least six hours of sunlight a day needed for optimum growth.
Temperature
Most rocky mountain blazing star species are fairly tolerant of the cold, able to tolerate temperatures down to -29 ℃. A few species are even more cold-tolerant than this, provided the soil has been mulched. The rocky mountain blazing star will thrive with little attention, provided it is in a sunny spot and its soil is well-drained. The plant needs about 2 cm of water a week during the heat of summer, otherwise growth may be stunted.
Watering
Rocky mountain blazing star thrives in its native environment, where it is accustomed to regular rainfall patterns. This species exhibits a preference for consistent moisture but can tolerate short dry periods. Watering should be done once every week to maintain its hydration needs. Given that rocky mountain blazing star is more commonly grown outdoors, it’s important to consider the impact of seasonal rain on its watering schedule, particularly for those planted in garden beds or naturalized areas.
Soil
Most rocky mountain blazing star species are fairly tolerant of the cold, able to tolerate temperatures down to -29 ℃. A few species are even more cold-tolerant than this, provided the soil has been mulched. The rocky mountain blazing star will thrive with little attention, provided it is in a sunny spot and its soil is well-drained. The plant needs about 2 cm of water a week during the heat of summer, otherwise growth may be stunted.
Fertilizing
For optimal growth, fertilize rocky mountain blazing star with a balanced fertilizer in spring as growth resumes. During the budding phase, switch to high-phosphorus fertilizer to enhance flowering. Apply quarterly, avoiding over-fertilization to prevent foliage at the expense of blooms. Monitor growth stages, reducing fertilization in fall and pausing in winter. Utilize recommended quantities on labels; overuse can damage roots. Ensure even application and water thoroughly afterward for nutrient absorption. This regimen promotes vigorous growth, robust blooms, and overall plant health.
Planting Instructions
When planting, the soil should first be covered with a 5 cm layer of compost. A 10 cm hole should then be dug through both the compost and soil underneath for each rocky mountain blazing star plant, with holes for each plant set 10 cm apart in each direction. Once the corms are placed and the soil tamped down over the bulbs, a thorough watering should be applied to settle down the soil. The bulbs should begin to develop roots and sprout within a few weeks. Despite its long stems and flowers, the rocky mountain blazing star rarely needs staking and self-supports unless its soil is soggy.
Pruning
It is important to deadhead the rocky mountain blazing star as flowers begin to fade. As soon as flowers start to fade, stems should be cut back to basal stems to prevent the plant from going to seed and ending its blooming season early. Pruning the stalks at the end of the season helps to stimulate vigorous growth for the following season. End of season pruning should be done by cutting the stalks back to 5 to 10 cm above the ground and covering the stalks with leaves or straw.
Propagation
A native perennial cherished for its vivid blooms, rocky mountain blazing star thrives when propagated through division, a method best conducted in the early spring or fall. Carefully split the established clumps, ensuring each division has a robust section of roots. Replant the sections at the same depth as the original plant, maintaining ample spacing to accommodate growth. This method allows gardeners to expand their collection effectively while preserving the vigor and floral display unique to rocky mountain blazing star.
Transplanting
For vigorous growth, transplant rocky mountain blazing star in the warmth of early to mid-summer, when the conditions catalyze root establishment. Choose a sunny location with well-draining soil. If necessary, amend soil with organic matter to enhance vitality.
III. Uses and Benefits
Rocky mountain blazing star is an excellent choice for perennial borders, cottage gardens, or native plant gardens, prairies, and meadows. Great as fresh-cut flowers or in dried arrangements.
IV. Harvesting and Storage
Once blooming is finished later in the year, seeds can be collected easily. For collecting seeds, a stalk can be cut off once it has finished blooming and has dried. The seeds can be stripped from the stalk by hand.