Inspiration from the PPA Symposium by Erik Petersen

Recently I had the opportunity to attend an amazing conference hosted by the Perennial Plant Association.  Held in Denver, Colorado, the overall theme was plants that perform well in high mountain areas, barren soils and low water settings.  The Rogue Valley fits squarely into this designation.

While there was certainly a lot of discussion about new plants and plant selections, I found many of the big picture concepts to be really eye opening about the current state of gardening we find ourselves in and heading into.

Regional Appropriateness

For years there has been a heavy presence of either East Coast plant material or plants that thrive on the East Coast that has been marketed across the entire United States in a one size fits all category.  Botanist, breeders and gardeners alike have started to shift away from this mentality and focus more on either western forms or regionally appropriate selections that will thrive in the Western United States.  As an example, some ornamental grasses originating from overseas or the Eastern U.S. or the mid-west struggle in our arid soils containing low organic matter and a high pH.  New western forms such as Bouteloua ‘Blonde Ambition’ (Blonde Ambition Grama Grass) or Sorghastrum nutans ‘Thin Man’ (Thin Man Indian Grass) are excellent examples of grasses that are regionally appropriate since they perform well in our area.

Another issue this area deals with is that we do not get the natural summer and fall rains the east coast does so this factors into what plants will regionally thrive in this area.  Gardeners and designers from around the country are envious that we can grow Arctostaphylos (Manzanitas), Ceanothus (California Lilac) and Rhamnus ‘Eve Case’ (Coffeeberry) here.  These evergreen shrubs won’t miss a beat in our dry summers and early fall and as such we should embrace our region’s environmental uniqueness and plant accordingly.

Alliums (Ornamental Onions) while not always native, are another wide-ranging species that perform exceptionally well here.  They can thrive in dry soils that drain well and are devoid of lots of organic matter.  There are literally dozens of forms to choose from but a few highlights from the conference were:  Allium ‘Millenium’ (2018 Perennial Plant of the Year), Allium ‘Christophii’ (Huge ornamental heads with steel-blue flowers) and Allium thunbergii ‘Ozawa’ (A fall blooming selection).  Alliums are incredible pollinator plants that provide both pollen and nectar for beneficial insects.

Having a love affair with the hose when the trends suggest otherwise!

One of the top current trends in gardening is gardens that are low water and adaptive to the conditions.  For a resource in that is often scarce and expensive (water) there are plenty of plants that can be solutions to this need.  Many plants that are regionally appropriate for this area do not want constant or copious amounts of water once they are established in the ground since this can be detrimental to the plants or lead to their death.  Plants such as Agastache (Hummingbird Mint), Arctostaphylos (Manzanita), Penstemons (Beardtongue) and Eriogonum (Buckwheats) and ornamental grasses in general are all water wise plants that thrive in our region and have many attractive qualities about them.  When summer temperatures and heatwaves consistently reach over 90 degrees plants such as these usually go into a hibernation phase of sorts where they stop growing and ride out the heat until temps return to normal.  As gardeners, our natural inclination is to water more as the temperature increases which is often the exact opposite of what we should do.  A once or twice a week deep watering of plants in the ground will be adequate to meet their needs.  Over watering leads to rotting of the roots or stressing the plants.  Designing gardens with low water needs but that also exhibit desirable ornamental qualities is the current and future trend.  Other amazing perennials that are adaptive, low maintenance and drought tolerant are:  Monardella (Coyote Mint), Zauschneria (California Fuschia), Delospermas (Ice Plants), Hesperaloe (Red Yucca) and Sedums (Spreading Stonecrop)

New Concept of value of plants.

The traditional benefits of plants were promoted and thought of as “items” that brought happiness, beauty and increased property value to our life.  Over time new concepts have risen to the top as to the value that plants bring into our world.  Today’s cutting-edge designers are thinking about how plants can help with improved water and air quality, providing food (both to humans and animals), their functionality and how they benefit wildlife.   Many plants can serve multiple functions and overlap criteria when it comes to designing.  For example, Panicum grasses (Switch Grass) serve multiple uses.  Not only are they extremely drought tolerant (their roots can go down 14’) but they sequester carbon from the air and put it in the ground thus helping with air pollution.  Their foliage is very attractive and their seed heads can be a food source for birds.  This is an example of one plant providing at least four sources of value, not all of them just for humans.

I came away from the Perennial Plant Conference with a new sense of looking at how plants are being used, valued and incorporated in today’s designs and projects and what our responsibility as gardeners, landscapers, designers and plant propagators is in today’s changing world.

-Erik Petersen