Wood sage (Salvia × sylvestris 'Blauhügel' BLUE HILL)
Salvia × sylvestris 'Blauhügel' BLUE HILL (Wood sage) offers showy blue spikes, low maintenance, and excellent drought tolerance for sunny borders.
Complete Plant Information
Overview
Salvia × sylvestris ‘Blauhügel’ BLUE HILL, commonly known as Wood sage, is a prized herbaceous perennial valued for its reliable summer color display. This hybrid salvia features dense, upright spikes of pure blue flowers that reliably bring visual interest to perennial plantings from late spring into early summer. It is celebrated for its low maintenance requirements and excellent performance in sunny, well-drained conditions.
Gardeners appreciate the sturdy nature of Salvia × sylvestris ‘Blauhügel’ BLUE HILL. Though happiest with regular moisture, this Wood sage variety tolerates drier conditions once established, making it a dependable choice for hot, sunny borders. Its upright architecture provides excellent vertical contrast against mounding perennials.
The aromatic foliage and striking bloom spikes ensure that Salvia × sylvestris ‘Blauhügel’ BLUE HILL remains a garden favorite, serving well in cottage designs, mass plantings, or as a long-lasting element for fresh or dried arrangements. It represents the best traits of perennial salvias for reliability and aesthetic appeal.
Fast Facts
- Plant Family: Lamiaceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 4-8
- Size at Maturity:
- Height: 1.5-2 ft
- Spread: 1-1.5 ft
- Bloom Time: May to June
- Bloom Description: Blue
- Sun Exposure: Full sun
- Water Needs: Dry to medium
- Maintenance Level: Low
How to Grow
Plant this Wood sage in spring or fall, ensuring the location provides full sun exposure for the best bloom production. It thrives in average, well-drained soils, preferring conditions that are on the drier side but can also handle moist, humusy loams provided drainage is superior. Good drainage is critical for the long-term health of Salvia × sylvestris ‘Blauhügel’ BLUE HILL.
Maintenance for this perennial is generally low. While it tolerates drought, consistent moisture during the primary bloom time will encourage repeat flowering throughout the summer. Deadhead spent flower spikes promptly; this simple step helps extend the blooming period significantly.
Be aware that in very hot, humid climates, the plants may become somewhat floppy or open up by mid-summer. If the plants lose their tight form, cut them back hard to the basal foliage to refresh their appearance. At the end of the season, after all flowering concludes, shear the plants back completely. This variety performs best when night temperatures remain cool, typically thriving north of USDA Zone 7.
Landscape Uses
Salvia × sylvestris ‘Blauhügel’ BLUE HILL is an indispensable component for structuring perennial borders. The dense spikes of blue flowers are especially effective when massed or planted in drifts, creating waves of color that draw the eye. It functions beautifully as an accent plant, punctuating drifts of lower-growing foliage plants.
Consider using the 1.5 to 2-foot height of this Wood sage variety in the middle ground of mixed flower beds. It pairs exceptionally well with contrasting colors and textures, such as silver foliage plants, pale yellow daylilies, or white-flowering Shasta daisies. Its versatility also lends itself to the relaxed style of cottage gardens or more naturalistic wild gardens where drought tolerance is a plus.
Because the flowers hold their color well, this variety is highly recommended for gardeners seeking long-lasting material for cut flower bouquets. Even after flowering, the spent stems can be saved for their texture in dried arrangements, making this a multi-season performer.
Standout Features
Flower Qualities
- Showy
- Good Cut
- Good Dried
Noteworthy Characteristics
Salvia × sylvestris, often commonly called wood sage, is a hybrid perennial salvia that primarily results from crosses between S. Nemorosa and S. Pratensis. Some cultivars currently listed under S. × sylvestris have uncertain parentage, however, and may actually be cultivars of one of the parents rather than being hybrids. Moreover, The Plant List considers a large number of hybrids sold in commerce today under different names to be synonyms of S. × sylvestris, including S. × alpestris, S. × asperula, S. × collina, and S. × superba. Salvia × sylvestris plants, by and large, are branched, upright, clump-forming, perennials featuring opposite, oblong to lanceolate, medium green leaves and showy spikes of tiny, tubular, two-lipped flowers (each to 1/2” long) which range in color from blue to lavender to purple. Flowers primarily bloom from late spring to early summer, but sporadic additional bloom may continue to appear throughout much of the remaining summer. Flowers bloom in 2-6 flowered verticillasters arranged in dense terminal racemes which rise well-above the basal leaves on square stems to as much as 30” tall. Subsequent to the primary bloom, sporadic additional bloom may continue to appear throughout much of the remaining summer. Leaves of this mint family member are aromatic, wrinkled and soft-hairy beneath with entire or serrate margins. Basal leaves (to 3” long) have petioles. Smaller upper stem leaves are sessile.The genus name Salvia comes from the Latin word salveo meaning “to save or heal”, in reference to the purported medically curative properties attributed to some plants in the genus.Hybrid name of sylvestris comes from Latin meaning of or pertaining to forest or wood.Wood sage has a variety of common names including violet sage, ornamental meadow sage, Balkan clary, purple flowering sage or perennial woodland sage.‘Blauhugel’, commonly sold under the trade name of BLUE HILL, features pure blue flowers on stems rising to 20” tall.
Tolerances
- Deer
- Drought
- Dry Soil
Potential Problems
While generally low-maintenance, this Wood sage can occasionally face issues typical of members of the mint family. Be watchful for fungal diseases such as powdery mildew, leaf spot, or rust, especially if air circulation around the clumps is poor or high humidity persists. Good spacing during planting assists heavily in mitigation.
In terms of pests, spider mites, lacebugs, whiteflies, and scale insects are occasional nuisances to watch for on Salvia × sylvestris ‘Blauhügel’ BLUE HILL. Inspect the undersides of the leaves regularly, particularly during hot, dry spells when spider mites thrive. Healthy soil and proper watering minimize stress, increasing the plant’s natural resistance to pests.
Frequently Asked Questions
What hardiness zones is Wood sage suitable for?
Salvia × sylvestris ‘Blauhügel’ BLUE HILL is reliably hardy in USDA Zones 4 through 8, offering a broad planting range across temperate climates.
How large does Salvia × sylvestris ‘Blauhügel’ BLUE HILL grow?
This variety typically reaches a mature height between 1.5 and 2 feet tall, with a spread ranging from 1 to 1.5 feet wide.
What sun exposure does Wood sage need?
This plant requires full sun exposure to develop the necessary energy for its strong bloom display and to help maintain upright stems.
When does Salvia × sylvestris ‘Blauhügel’ BLUE HILL bloom?
The primary bloom period is late spring to early summer, specifically noted as May to June, featuring vibrant blue flowers.
Conclusion
The reliable stature and brilliant blue spikes of Salvia × sylvestris ‘Blauhügel’ BLUE HILL make it an essential anchor in sunny perennial gardens. Its low maintenance and tolerance for drier sites ensure vibrant color year after year. Before planting, always confirm that your site conditions align with the USDA Zone 4-8 hardiness range and full sun requirement for optimal results with this Wood sage.
Propagation Tips
Propagation of Salvia × sylvestris ‘Blauhügel’ BLUE HILL can be successfully achieved through two primary methods: softwood cuttings or division. Softwood cuttings, taken from new, flexible growth in the spring or early summer, root well and allow you to multiply successful, desired cultivars quickly.
Division is best performed in early spring just as new growth begins to emerge, or alternatively, in early fall. Carefully dig up the established clump of Wood sage and gently tease apart the root ball into several smaller sections, ensuring each section has adequate roots and crown tissue attached. Replant these divisions immediately into prepared soil. Note that some hybrid wood sages can be sterile, so while division reliably reproduces the exact cultivar, starting from seed may not yield plants true to the parent ‘Blauhügel’ characteristics.
Wildlife Benefits
As a member of the mint family, Salvia × sylvestris ‘Blauhügel’ BLUE HILL is highly attractive to foraging pollinators. The tubular blue flowers are perfect structures for long-tongued bees and hummingbirds seeking nectar rewards from late spring onward.
Planting masses of this type of Salvia provides a substantial and consistent late-spring nectar source when other flowers may be slowing down. While the foliage has deer and rabbit resistance, the flowers actively draw beneficial insects, vastly improving the ecological value of your mixed borders or cottage garden.
