Plant Profile: Pitcher Sage, Salvia azurea

During the doldrums of late summer, light blue flower spikes thrusting skyward along Kansas roadsides and prairies provide welcome contrast to the yellows of the state’s many sunflowers.  Pitcher sage, also known as blue sage or pitcher plant, is a delicate looking prairie native with ironclad constitution. 

Salvia azurea, also known as blue sage, is a member of the MINT FAMILY.

Pitcher sage is a somewhat common plant in the rocky areas of the tall and mixed grass prairies. This plant is an erect, hairy perennial ranging in height from one and a half to four feet with short, thick rhizomes (horizontal underground stems). Very adaptable to garden situations, it prefers drier soil in full sun. In sandy sites it has been known to self-seed, but this is seldom a problem in clay loams. The crowns can slowly broaden from rhizomes as the plant matures. 

Pitcher sage blooms from late July to early October, although peak bloom is early September in most years. It is blooming right now in our Prairie Window Project in the south part of the Arboretum. The light blue flower color is common in prairies around south central Kansas. There is a cultivated variety, Salvia azurea “Grandiflora,” that displays an intense deep blue flower. Once established, it requires water only during extended dry periods. 

Besides the unique light blue coloration, the flowers possess an unusual mechanism to ensure cross-pollination. The corolla is lobed with a narrow concave lip covering the style (female) and the anthers (male) which mature at different times in the same flower. The lower lip is broad and protruding, providing a landing pad for visiting honey bees, bumble bees and other pollinators.  The bee grasps the platform, thrusts its head down into the throat of the flower and pushes its sucking mouth parts into the nectar glands. By this action, the bee is simultaneously pushing down on the structure at the base of the stamens. This causes them to descend from the upper lip spreading pollen on the bee’s back. As the bee visits other flowers, it spreads pollen to receptive styles. 

Bumble bee in search of some nectar.

The Arboretum grows pitcher sage for its late summer color and the bee activity it provides.  The plant is a bee magnet in full bloom. It is always entertaining to watch lumbering, black and yellow bumble bees wrestle their way into the flowers in search of nectar while unwittingly carrying the promise of another seed crop on their striped backs.   

To the Pond and Beyond

Many people think that the phrase “native plant” is synonymous with “drought tolerant plant” or “dry prairie species”. But not so! Kansas is a place full of sunny skies as well as quiet, shady streams; prairies as well as ponds. I noticed at our FloraKansas event last week just how many wetland and pond species we offer. For those with small backyard ponds or even large country creek banks to restore, the following species might be perfect for you (and we still have them in stock! Find our updated inventory here.)

Caltha palustris – Marsh Marigold

Marsh marigold is adorable along pond edges and in water gardens.

Caltha is an upper midwest native, not usually found in Kansas, but can grow here under the right conditions. We don’t get enough ran to sustain swampy areas where it can run wild, but its petite yellow flowers are happy blooming along pond edges with their feet in the water. We are hoping to get them established along the Arboretum pond edges this year.

Teucrium canadense – American Germander

Laval University, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons

A colony-forming mint family plant, it can go wild in moist to wet part sun conditions! The blooms are attractive to long-tongued pollinators, and they make great additions to wildflower bouquets.

Nyssa sylvatica – Black Tupelo

Black tupelo in New York state. Photo from Wikimedia commons

A truly beautiful tree, unmatched for its red fall color. But in our region it simply cannot survive without moist soil. Planted on the edge of a stream or in a frequently flooded drainage area, it would be stunning every October.

Cephalanthus occidentalis – Buttonbush

Public domain image from US Fish and Wildlife Service

The height of this fascinating shrub depends on the moisture it receives: growing near standing water it can be 10 feet tall or more, but in average garden soil it may only reach 6 feet. Very adaptable and easy to care for, its spherical flowers are long blooming. In June they are covered in bees, beetles, butterflies, spiders, wasps, and every other flying thing!

Lythrum alatum – Winged Loosestrife

Joshua Mayer, CC BY-SA 2.0 https://creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons

Not to be confused with the terribly invasive purple loosestrife (Lythrum salicaria), this petite plant sports purple flowers and wiry stems. Very adaptable, it is used in rain gardens, but thrives in garden settings given a bit of shade and semi-regular watering. The Lurie Garden of Chicago has a nice profile on this species found here.

Lobelia siphilitica – Blue Cardinal Flower

Blue lobelia photo courtesy of the US Fish and Wildlife Service

The tall blue spikes of lobelia attract hummingbirds and butterflies, but they can be finicky to grow. Clay soils that hold moisture are best, and while they don’t have to be situated in water at all times they do best in ditches and frequently wet seasonal streambeds.

While we know not many people are lucky enough to have a pond or creek on their property, for those that do, we want to continue suppling a small number of wetland plants to help you restore and improve those places.

Other water loving species to look for next spring: Acorus calamus, Lobelia cardinalis, Physostegia virigniana, and Sauurus cernuus. For more info on wetland plants, check out a previous blog post all about them!

Plants for hillsides and slopes

One of the more common landscaping conundrums is deciding what to plant on steep slopes or hillsides. These areas require plants that can establish quickly, have fibrous root systems, that hold soil to control erosion, are tolerant of fluctuating soil moisture and potentially poor nutrient availability, and require little care once established.

Slopes and hillsides are already challenging because of sun exposure, and the degree of the slope only exacerbates the problem. Establishing plants from seed is the most economical choice, but is also the most subject to erosion for the first 3 to 5 years until plants get established. Often, turf grass such as fescue, buffalograss, or bermuda grass is the first groundcover choice for keeping soil in place, but mowing these sloped areas can be a challenge, maybe even dangerous. Turf does not create much habitat for wildlife and pollinators either.

There are many plants that will establish cover more quickly than seed. These native plants offer a lower maintenance alternative to a mowed lawn. The following list is just a start. Remember to plant more densely (1-2 feet apart) so the area gets completely covered with plants quickly.

Grasses

The following grasses, with their extensive fibrous root systems are ideal plants to stabilize a steep area and prevent soil erosion.

  • Andropogon geradii (Big Bluestem)
  • Bouteloua curtipendula (sideoats grama)
  • Chasmanthium latifolium (River oats)-Can grow in sun or shade but is aggressive. It will spread by seed and rhizomes to crowd out most other plants.
  • Elymus canadensis (Canada wildrye)
  • Panicum virgatum (Switchgrass)
  • Schizachyrium scoparium (little bluestem)
  • Sporobolus heterolepis (prairie dropseed)
Little Bluestem with Aromatic Aster and New England Aster

Wildflowers

  • Achillea millifolium Yarrow
  • Allium cernuum Nodding onion
  • Amsonia sp. Blue star
  • Aquilegia canadensis Columbine
  • Asclepias tuberosa Butterfly weed
  • Baptisia australis False blue indigo
  • Dalea purpurea Purple Prairie Clover
  • Echinacea purpurea Purple coneflower
  • Eutrochium (Eupatorium) maculatus Joe-pye weed
  • Filipendula rubra Queen-of-the-prairie
  • Liatris pycnostachya Prairie blazing star
  • Liatris spicata Dense blazing star
  • Rudbeckia sp. Black-eyed Susan
  • Penstemon digitalis Penstemon
  • Symphyotrichum oblongifolium Aromatic aster
  • Solidago sp. goldenrod
  • Tradescantia ohiensis Spiderwort
  • Veronicastrum virginicum Culver’s root
Amsonia ‘Butterscotch’ and Aster ‘Raydon’s Favorite’ with mulch between plants to control erosion.

Trees and Shrubs

  • Amelanchier canadensis Serviceberry
  • Cercis canadensis Redbud
  • Coruns sp. Dogwood
  • Crataegus viridis Hawthorn
  • Heptacodium miconioides Seven Son Flower
  • Ilex verticillata Winterberry holly
  • Lonicera reticulata Grape honeysuckle
  • Prunus Americana Wild Plum
  • Prunus sp. Sand cherry
  • Prunus virginiana Chokecherry
  • Rhus aromatica Fragrant sumac
  • Sambucus canadensis Elderberry
  • Viburnum prunifolium Blackhaw Viburnum

If the erosion is already very serious, you might want to consider using erosion-control blankets to stabilize the erosion area until the plants can take over the job. The erosion-control fabric works by slowing the runoff water and allowing sediments to fall out rather than be washed away. Choose a mat that will decompose over time, e.g. straw or jute, rather than something made of plastic. Start by slicing a small opening in the mat so plants can be put into the soil beneath. I recommend hand watering during establishment as much as possible since sprinkler irrigation can increase soil erosion.

For more gentle slopes, heavy mulch or pea gravel can be used to control erosion during establishment. Each slope situation is unique, but if you can, the best strategy for stabilizing a slope with plants is to establish vegetation at multiple levels—plant trees, shrubs, grasses and wildflowers. A multi-level canopy will do the best job of intercepting and slowing precipitation before it hits the ground, reducing surface erosion. Different vegetation types also provide both deep and spreading roots that stabilize the entire soil profile. Generally, it takes 2-4 years to get these plants fully established and roots anchored into the slope.

Slopes covered with a variety of grasses including switchgrass and fountain grass at Wichita Art Museum. Photo by Brad Guhr