How to Grow and Care for Russian Sage

Russian sage is a low-maintenance, drought-tolerant sub-shrub often grown as a perennial. Extremely tolerant of dry conditions, it is a great choice for xeriscaping. Its long blooming period is valued by those who seek a flower bed that remains in bloom throughout the growing season.

While once classified as Perovskia atriplicifolia, taxonomists reclassified in it 2004 through DNA testing as Salvia yangii, officially placing it in the sage genus. Russian sage is found in Asia in the mountains of Tibet and Afghanistan. You may see both Latin names listed in nursery catalogs for several years.

This bush produces panicles of small, bluish-lavender flowers throughout the summer and into fall. Not to be outdone by its flowers, the plant's stems and foliage make a strong statement of their own, perhaps even outstripping the floral display as the chief reason to grow the bush, A graceful perennial with silver stems (so chalky in appearance they sometimes seem to be white) and feathery, silvery leaves, Russian sage plants can reach a height of four to five feet with a spread of three feet or greater if you do not prune them annually.

Russian sage is a fast grower that is best planted as a nursery-grown container plant in the late spring when the soil is warm but before the weather is too hot and dry. If you plant later, water frequently to keep the plants from drying out.

Russian Sage Care

Russian sage is a tough plant that needs little care. Since it is so tall, if grown individually, it often requires support with stakes or a peony ring, If grown in masses, the plants help to support one another. The primary care is pruning, though even this is optional.

As a member of the mint family, the Russian sage spreads by runners and needs to be monitored to keep it out of places where you don't want it to spread. Pull up suckers in the early spring. Divide the plants every four to six years to refresh them.

Light

For best results and blooms, plant Russian sage in full sun. Shady conditions tend to make the plant leggy and prone to collapse.

Soil

These bushes thrive in dryish, well-drained soil, including sandy soil, but may develop root rot in dense, poorly drained conditions. They prefer alkaline soils of pH 7 and greater but can tolerate a wide range of soil pH (6.5–8.0).

Water

New transplants need regular watering, but once established, Russian sage is very drought-tolerant. It likes medium to dry soil and will do fine in hot, dry areas of your yard or garden. Russian sage will not grow well in excessively wet, poorly-draining soil.

Temperature and Humidity

Indigenous to central Asia, is reliably hardy in planting zones 5 through 9 and it often survives in zones 3 and 4 if you provide some minimal protection during winter. Warmer regions will see this plant behave as a semi-woody shrub, while gardeners in zones 3 and 4 will treat it as a perennial that dies back to near ground level each winter.

Fertilizer

This plant is easily grown in average, dry to medium, well-drained soils. At most, you might provide a light layer of compost in the spring. It responds poorly if given too much fertilizer, especially nitrogen.

Types of Russian Sage

Though Russian sage was known as Perovskia atriplicifolia, DNA sequencing done in 2004 reclassified this plant in the Salvia genus. Academic resources now list Russian sage as Salvia yangii—although the old botanical name persists, especially in the nursery trade.

When the pure species is sold, it is usually Perovskia atriplicifolia that is offered. The named cultivars usually are sold simply as Perovskia, and they may be either cultivars of P. atriplicifolia or cultivars of a hybrid cross betweenP. atriplicifoliaandP. abrotanoides. The cultivars most often offered in the nursery trade include:

• Perovskia 'Little Spire': a dwarf varietythat matures at about one to two feet tall, with a similar spread
• Perovskia 'Blue Spire': deeper blue-violet flowers on plants growing two to three feet tall and wide
• Perovskia 'Filagran': finely cut leaves and an airy appearance
• Perovskia 'Longin': more rigidly upright and narrower than the species plant and has slightly larger leaves
  
• Perovskia ' Blue Haze’: paler blue flowers and nearly entire leaves (not finely cut)
  

Pruning

Many gardeners, even in regions where the plant is evergreen, choose to severely prune Russian sage annually. The argument for pruning is that the plant will grow to be bushier the next season. And in cold-winter zones where the plant dies back each year, hard pruning is mandatory.

Pruning can be done in the fall, but you may want to leave the silvery stems in place over the winter for visual appeal. With this approach, the hard pruning is done in early spring. Whenever you prune, it's best to cut the stems back to 8 to 12 inches, which retains an ample number of growth buds that will resprout.

In regions where the plant is evergreen, you can selectively cut back dead or under-performing stems as they identify themselves in mid-spring.

Propagating Russian Sage

Although propagation by rooting stem cuttings is possible (and does produce offspring that are true to the parent plant), it can be a slow process that sometimes fails. A more reliable method is to propagate through basal cuttings. Here's how to do it:

1. After the stems have been cut back to 8 to 12 inches, begin watching for new growth in spring, which will usually be evident by mid-spring. Using a sharp knife or trowel, cut away one of the growing stems along the edges of the root ball, making sure to capture a healthy section of roots along with the growing stem.
2. Immediately plant this basal cutting in a small pot filled with a porous potting mix, such as a cactus/succulent mix, or in its new garden location.
3. Keep the potted cutting moist and place it in a well-lit location until new growth is evident. At this point, the rooted cutting can be planted in its new garden location.

Full division of the plants by digging up the root ball, dividing into pieces, and replanting, should be done every four to six years to maintain the health of the plant.

Russian sage may also reproduce itself by natural layering—stems that flop over and touch the ground may sprout roots and begin growing as independent plants. These self-layered volunteers can be severed from the mother plant, dug up, and transplanted into new locations.

How to Grow Russian Sage From Seed

Named cultivars of this plant usually do not produce seeds that "come true" to the parent plant, so seed propagation is not common. Pure species plants (non-named plants), however, can be propagated from seeds sown at any time of the year. Sow the seeds in pots filled with a porous growing medium, just barely covering them. Set in a protected location that receives plenty of light and keep the growing medium lightly moist. Germination will take one to four months at a temperature of 60 to 65 degrees Fahrenheit. When the seedlings are large enough to handle, they can be transplanted into larger pots for continued growth. If starting the seeds indoors, harden off the seedlings for a week or two before planting them in the garden in late spring.

Potting and Repotting Russian Sage

Though container culture is not the typical use, Russian sage will grow well in any well-draining container filled with a porous potting mix, such as a cactus/succulent mix. Avoid very rich potting mixes, as these are not ideal for this plant. A potted Russian sage offers a good way to enjoy this long-blooming plant in sunny paved courtyards or patios. It can look very nice in ornamental clay or ceramic pots, and in warm-winter regions, it will offer ornamental appeal year-round.

Perennial plants such as Russian sage always offer some challenges for gardeners in cold-winter regions, as the exposed roots can be more prone to winter kill. Therefore, it's best to move potted Russian sage plants to a sheltered location after cutting them back for the winter. One option is to bury the entire pot up to its rim for the winter. Or, you can move the plant to a cold frame or unheated porch or garage until spring.

Repotting should be done whenever the plant is ready for division. Potted plants will require this every couple of years.

Overwintering

In warmer regions, no winter preparation is needed at all, other than hard pruning if you want to rejuvenate the plant. In cold-winter regions (zones 3 and 4), cover the plant crowns with a thick layer of mulch for the winter to protect the roots from freeze-thaw cycles. Remove the mulch promptly when new growth begins in the spring, as it's important not to trap moisture around the roots.

In extremely cold winters, it's not uncommon for Russian sage to perish, even if protected with mulch. Gardeners in zones 3 and 4 should not be surprised if a Russian sage fails to return after an especially harsh winter.

Common Pests & Plant Diseases

These aromatic plants tend to repel most common insects, and the only significant disease is root rot which can occur if the plants are growing in wet, poorly draining soil. Plants are especially susceptible to wet winter soil.

How to Get Russian Sage to Bloom

In the right conditions, the small blue or purple flowers of Russian sage will provide airy color for the entire summer, right up until frost. Failure to bloom is usually traced to a lack of sunlight, as these plants grow leggy with sparse blooms if they don't get a full six hours or more of direct sunlight daily.

Excessive fertilizing also compromises flower production, as nitrogen causes the plants to develop leggy growth at the expense of flowering. If your plants aren't blooming the way you want, try withholding all feeding, even the light topdressing with compost that is normally advised.

Young plants may take a full year or two before they are fully established and begin to bloom robustly. Don't worry about a lack of flowers until the plant is fully two years old.

Common Problems With Russian Sage

The most common complaint with Russian sage is sprawling, floppy stems. With some varieties, this is almost unavoidable and the plants may require a hoop support or other means of staking to keep the plants more upright.

Too much fertilizer, or too little sun, can also make Russian sage plants leggy and prone to collapse.

From: thespruce