How to Plant, Grow, and Care For Clary Sage

Clary sage produces towering lilac blooms all summer in its prime growing conditions. The tall stems create a mass of soft color and offer a pleasing musky fragrance with centuries-old popularity for its essential oils. The tubular blooms are high in nectar and attract butterflies, native bees, and other pollinators.

The perennial herb bridges the edible landscape and ornamental border. It’s prime for cottage and rock gardens, naturalized arrangements, and pollinator plantings.

Pair clary sage with other summer-blooming perennials for sweeping color and ecosystem services like erosion control and drought tolerance. Use them among other herbs and blooms to draw biodiversity to the vegetable garden. These tough bloomers thrive with a little neglect; give them space to resed or deadhead them to prevent volunteers.

What is Clary Sage?

Clary sage boasts a long bloom season, offering a wash of pastel shades in lilac, creamy white, and pink from June to August. The biennial or short-lived perennial lives for two to four years. In its optimal growing conditions, it reseeds for a continual crop of abundant blooms.

Arrange this Salvia in groups or drifts for the most impact. It pairs well with other summer-blooming perennials like coreopsis, echinacea, rudbeckia, lavender, and even roses. The shrubs bring a full backdrop or mid-layer to the border.

Clary sage has historical uses as a medicinal herb, but is grown mostly for its high ornamental value, ease of care, and fragrance in soaps and cosmetics. The edible leaves and flowers flavor oils, foods, and drinks, from beer to wine to liqueurs.

Characteristics

Clary sage has distinctly aromatic foliage and flowers. All summer, the tall, lavender spikes appear in a mass above basal leaves. In the first year, roots and foliage develop. Three- to four-foot flowering stems rise above basal leaves in the second growing season. 

The tubular blooms are two-lipped in cream and lavender and surrounded by tissuey bracts in lilac-pink. The flowers are small but numerous as they whorl around the multi-branching stems. These perennials have a clumping, mounded form with upright stems.

Each flower produces four nutlets that ripen in September, and each holds a seed. Birds enjoy them for forage. Clary sage’s easy reseeding allows it to escape the garden and naturalize in its optimal growing conditions. It volunteers in parts of the northern and central United States and is a Class A noxious weed in Washington state, where it has the potential to displace native species.

The aromatic foliage and essential oil, coupled with hairy leaves and stems, make salvia distasteful to deer. Like other salvias, crushing the leaves brings an earthy, balsam scent.

Native Area

The short-lived perennial is native to the Mediterranean basin, including Europe, Central Asia, and Northern Africa. In its natural range, it grows in open woodlands, meadows, on rocky slopes, and along roadsides.

In the Mediterranean, summers are hot and arid, followed by cool, wet winters. Sandy, rocky, well-draining soils and dry conditions are a natural fit for this salvia.

Planting

The flowering herbs reseed to expand the colony and propagate from seed. At planting, space them one to three feet apart to allow room to spread. They reach two to three feet wide at maturity.

Clary sage thrives in warm temperatures. Direct sow seeds after the final frost as soil and air temperatures warm. To get a jump start on growth, start seeds indoors six to eight weeks before the final frost. 

How to Grow

The low-maintenance herbs tolerate a range of conditions, including dry, sunny sites, shallow soils, and coastal exposure. They thrive with neglect but won’t perform well in shade or hot, humid conditions.

Light

Salvia sclarea is from the sun-drenched Mediterranean and shows the strongest stems and blooms in full sun, with six or more hours daily. In too much shade, plants develop spindly, weak stems and produce few to no flowers.

Water

The flowering perennial is drought-tolerant and withstands dry conditions. Regular moisture promotes vigor as long as the growing situation is well-draining.

Avoid prolonged wet and saturated conditions, as they lead to weakness and potential diseases like powdery mildew. Wet winters and soggy soils cause additional fungal problems like root rot.

Soil

Clary sage prefers loose, light, sandy loams but tolerates various types from moist to gravelly as long as they have good drainage. Salvia sclarea won’t thrive in wet soils and relies on quick runoff. The versatile growers are good for erosion control on slopes and in revegetated areas.

The rugged performer prefers average to lean soils, including shallow, rocky ones. In overly organic compositions, stems grow tall but won’t bear as many blooms.

Temperature and Humidity

The herb is hardy in zones 5-9, where it survives cold winters and mild summers. They don’t do well in hot, humid growing areas. They’re most likely to perennialize and live beyond two years in cool climates.

Fertilizing

Fertilizer isn’t necessary for S. sclarea to grow and flower. In dense soils like heavy clay, amend with compost to improve aeration and drainage. Remember that too much nitrogen leads to tall stems but few blooms for this rugged specimen.

Maintenance

The low-maintenance salvia is mostly carefree. Cut spent blooms before they go to seed first, to prevent unwanted reseeding, and second, to promote a third-year resurgence from the biennial.

If stems become leggy or less bushy in midsummer, give them a trim. Cut ⅓ of the way back to promote a fresh flush of growth and blooms. You can use viable stems for cuttings to propagate more salvia.

Mulch around seedlings (away from stems) for insulation and moisture regulation. For end-of-season care, cut back brown, dry foliage and stems after leaves completely die back after fall’s hard frosts, or let them naturally decompose in place.

Propagation

The short-lived perennial propagates easily through seed and cuttings. Take cuttings in late spring or early summer for fresh growth and let them establish in the warm season.

Growing From Seed

Direct sow seeds post-frost and as soil temperatures warm. Or, start them indoors six to eight weeks before your final frost date for earlier establishment, transplanting as the weather warms.

Sow the seeds by pressing them lightly into the soil surface with ¼ inch of coverage. For indoor sowing, use a grow light. Keep the potting media moist and warm, near 70°F (21°C), for the best germination. Look for sprouts to spring up in one to two weeks.

Cuttings

Take cuttings early in the growing season to capture fresh, pliable new growth. To take cuttings:

• Cut a four- to six-inch piece of stem from a healthy branch. Cut the stem at a 45-degree angle to ensure water and rooting hormone coverage.
• Remove the flowers and the leaves from the bottom ⅔ of the cutting (leaving at least two leaves).
• Optional: moisten the cutting and dip the lower stem in rooting hormone, coating generously. Tap off any excess rooting powder.
• Stick the cutting in at least two inches of moist, well-draining potting mix or perlite.
• Place the pot or tray in a bright, warm location, away from direct sunlight.
• Mist or water as needed to keep the soil evenly moist.
• When the cutting resists a gentle tug, roots are in place and ready to be repotted or moved to the garden. Keep soil moist but not wet for new seedlings, as the young plants will be tender.

Common Problems

The resilient clary sage is usually free of pests and diseases. Common garden pests are occasional problems, as are fungal diseases like powdery mildew, rust, and root rot. The best cultural conditions help stave off potential issues.

Pests

Sap-sucking insects like aphids and mites can become an issue, especially in cases of water fluctuations. Grow a diversity of blooming plants to attract beneficial insects that prey on common invaders. Natural predators like ladybugs, parasitic wasps, hoverflies, and lacewings provide natural pest control.

Aphids

Aphids colonize in numbers and feed on plant tissues. They’re pear-shaped and soft-bodied in light yellow, green, pink, brown, or black. They prefer soft, new growth and also leave behind sugary honeydew, leading to unattractive black, sooty mold. Severe infestation presents as curling, yellowing leaves and stunted growth.

Spray a strong stream of water early in the day to deter aphids by displacing them from leaves and stems. Horticultural soaps or oils like neem control more severe infestations. Follow label directions, as these treatments affect all insects, including pollinators. Time of day is essential in the application.

To prevent aphids, water evenly to achieve regular moisture. The insects gravitate toward drought-stressed specimens over healthy, well-watered ones.

Slugs and Snails

Slugs and snails may graze on fresh shoots and soft growth, but may only do minor damage. If you see the creatures or notice damage, handpick them early in the day or evening when they’re most active. In high numbers, bait them with beer or soda traps by filling a shallow dish and placing it at soil level.

Diseases

Common fungal diseases are seldom issues, but may occur in overly wet or humid conditions. Provide good air circulation through proper spacing and monitor watering to promote overall vigor.

Powdery Mildew

Powdery mildew is one of the most common fungal problems and appears as a grayish-white dust on leaves, buds, and stems. Leaves turn yellow, distort, and drop during severe infections.

Horticultural oils like neem can treat the problem early on. To ward off powdery mildew, take care not to overwater or overfertilize, which weakens the plant and increases susceptibility. Space them for ample airflow and follow proper watering to avoid damp conditions. Remove any dropped debris that can harbor spores.

Root Rot

Root rot is a common fungal disease that causes roots to decay, preventing them from taking up moisture and nutrients to support growth. For clary sage, this occurs in soils with poor drainage or prolonged periods of moisture, especially in winter.

Perennials in waterlogged compositions with poor airflow may show yellowing and wilting leaves. If you suspect rot, allow time for soils to drain before irrigating. Consider digging, clipping off brown roots, and replanting in higher ground with better porosity.

Rust

Rust is prevalent in hot and humid climates. You may see leaf spots and powdery spores on the undersides of yellowing clary sage leaves, which drop prematurely. Rust spreads easily, so remove any infected leaves or stems and discard them in a garbage bag or burn pile.

Horticultural oils like neem offer treatment. If it worsens, cut stems back to the ground and check fresh growth, or remove severely impacted specimens in decline.

The best way to prevent rust is to increase air circulation. Water at the base of the crown to deliver moisture to the roots without splashing foliage or harboring damp conditions.

Frequently Asked Questions