Aster (Aster sedifolius 'Nanus')
Discover Aster sedifolius 'Nanus', a low-maintenance herbaceous perennial aster offering abundant blue flowers from Aug to Sep in zones 4-7.
Complete Plant Information
Overview
Aster sedifolius ‘Nanus’ is a highly valued, compact cultivar of Aster known for providing reliable late-season color when many other garden plants are fading. This herbaceous perennial forms a dense clump, showcasing terminal sprays of lovely asters with blue rays and contrasting yellow centers, making it a superb choice for borders and late summer interest. Gardeners appreciate Aster sedifolius ‘Nanus’ for its manageable size, typically reaching only about 18 inches tall, which negates the staking often required by taller Aster species.
Native to Europe, this specific variety offers a significant aesthetic improvement over the taller, sometimes floppy species. The genus name Aster, meaning ‘star’ in Latin, perfectly describes the shape of these cheerful late-summer blooms that are highly attractive to butterflies. For a dependable fall display featuring beautiful blue tones, Aster sedifolius ‘Nanus’ is an excellent, low-maintenance selection.
Fast Facts
- Plant Family: Asteraceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 4-7
- Size at Maturity:
- Height: 1-1.5 ft
- Spread: 1-1.5 ft
- Bloom Time: August to September
- Bloom Description: Blue rays with yellow center disk
- Sun Exposure: Full sun
- Water Needs: Medium
- Maintenance Level: Low
How to Grow
Plant your Aster sedifolius ‘Nanus’ in a location that receives full sun exposure for the best bloom performance. This plant thrives in average, well-drained soils with medium moisture levels, making it quite adaptable for general garden settings. Good air circulation is crucial around the foliage, as this cultural best practice helps minimize the potential for foliar diseases like powdery mildew later in the season.
Care for this low-maintenance Aster is straightforward; maintain consistently medium moisture, especially during dry spells, but ensure the soil drains well to prevent root issues. Fertilization is rarely necessary if the soil is moderately fertile. While the species can be grown from seed, dividing established clumps of Aster sedifolius ‘Nanus’ every few years is the preferred method for maintaining vigor and increasing your stock.
As seasonal care progresses, ensure adequate cleanup in early spring. While the foliage of Asters can decline by late summer or early fall, you can often leave the dead stems standing through winter for interest, cutting them back hard in early spring before new growth emerges. Observing the plant closely can help you preemptively manage potential issues early on.
Landscape Uses
The refined, compact habit of Aster sedifolius ‘Nanus’ makes it an excellent structural element in formal or informal garden designs. It is perfectly suited for the front or middle of borders where its consistent height (1 to 1.5 feet) provides reliable structure without overwhelming neighboring plants. For cottage gardens, plant en masse to create drifts of late-season blue color.
This variety excels in butterfly gardens due to its late-season nectar availability, drawing in pollinators right up until frost. Consider pairing Aster sedifolius ‘Nanus’ with late-season grasses, hardy chrysanthemums, or plants that offer contrasting foliage textures, such as ornamental sedges, to enhance the visual impact as the season changes. Its need for full sun and medium water aligns well with many traditional perennial companions.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Aster sedifolius is native to Europe. It is a clump forming aster that features terminal sprays of 1.25” diameter asters (bluish-lilac rays with yellow centers) on generally weak stems rising 2-3’ (less frequently to 4’) tall. This species, sometimes commonly called Rhone aster, is infrequently sold in commerce because of the availability of the compact cultivar ‘Nanus’. Genus name comes from the Latin word aster meaning star for the shape of the flowers. ‘Nanus’ typically grows to only 18” tall and features flowers that are slightly smaller than the species with ray flowers that are a darker blue. Lance-shaped, medium green leaves (to 2.5” long). Blooms from late summer to early fall. Flowers are attractive to butterflies.
Tolerances
Potential Problems
Aster sedifolius ‘Nanus’ generally exhibits excellent resistance to serious insect pests and diseases, contributing to its low maintenance rating. However, Asters, as a whole group, possess some susceptibility to powdery mildew, a fungal issue exacerbated by poor air circulation or high humidity. Aster wilt can occasionally appear, particularly if the plant is situated in heavy, poorly-drained clay soils. Taller varieties may need structural support, but the ‘Nanus’ cultivar is often self-supporting due to its compact nature. Be aware that foliage quality can decline by late summer, which may prompt earlier cutting back than desired.
Frequently Asked Questions
What hardiness zones is Aster suitable for?
This dependable Aster sedifolius ‘Nanus’ is suitable for USDA Zones 4 through 7, providing reliable perennial performance across a wide temperature range.
How large does Aster sedifolius ‘Nanus’ grow?
Aster sedifolius ‘Nanus’ typically achieves a height between 1 and 1.5 feet, with a corresponding spread of 1 to 1.5 feet, making it a wonderfully manageable accent plant.
What sun exposure does Aster need?
For optimal health and the most profuse bloom display of its blue flowers, Aster sedifolius ‘Nanus’ requires full sun exposure.
When does Aster bloom?
This late-season bloomer brings color to the garden from August to September, offering bright blooms described as having blue rays with a yellow center disk.
Conclusion
For reliable, late-season structure and beautiful blue coloration, Aster sedifolius ‘Nanus’ stands out as a top-tier perennial choice. Its combination of rich flower color, pollinator appeal, and low maintenance requirements secure its place in many garden styles, especially cottage and butterfly designs. Before planting, confirm your location falls within USDA zones 4-7 and ensure you provide that necessary full sun exposure for best results with this stellar Aster.
Companion Planting
Selecting appropriate companions ensures your Aster sedifolius ‘Nanus’ performs optimally throughout the season. Look for plants that share a preference for full sun and medium water needs. Good neighbors include Sedum (Hylotelephium) varieties that finish blooming slightly earlier, offering foliage contrast after the Aster begins to flower. Consider planting shorter ornamental grasses, like certain varieties of Fescue or Hakonechloa, around the base to improve air circulation near the soil line and add textural variation right where the foliage of the Aster resides.
Propagation Tips
While you can attempt to start Aster sedifolius ‘Nanus’ from seed, the most effective and reliable method of propagation for this desirable cultivar is root division. Perform divisions in early spring, just as new growth begins to emerge, or in the early fall after the plant has finished flowering, though spring is usually preferred for faster establishment. Carefully dig up the established clump, gently separate it into sections, ensuring each new piece has a healthy portion of roots and several viable crown buds. Replant these divisions immediately into prepared soil at the same depth they were previously growing.
