WaterWiseGardening

A Conservation Gardening Approach

Linda R McMahanOSU Extension Servicelinda.mcmahan@oregonstate.edu

Photographs by the author unless noted.

What is WaterWise?

Waterwise gardening is a style that uses drought resistant plants to create landscapes that require minimal irrigation once established.

Penstemon, Nasturtium, and Santolinum species

Other Names: Xeriscaping, Water-Efficient Landscapes, WaterSense, Drought Tolerant

Why WaterWise?

R. St. Hilaire et.al, HORTSCIENCE 43(7):2081–2092. 2008.

• “Although water used to irrigate the residential urban landscape will vary according to factors such as landscape type, management practices, and region, landscape irrigation can vary from 40% to 70% of household use of water. So, the efficient use of irrigation water in urban landscapes must be the primary focus of water conservation.”

Why WaterWise?

From: http://www.clackamasproviders.org/water-efficient-plants/

What WaterWise is Not!

Not boring.Not all desert

plants.Not “Zero-

scaping.”Not maintenance-

free.

Private garden featuring waterwise plants and sustainable gardening techniques such as permeable paths, mulch, and recyled wood.

Objectives Conserve water-reduce

runoff of chemicals and nutrients.

Create sustainable gardens that are lower maintenance.

Use non-invasive species. Focus on prairie plants,

native plants, certain plants native to the US, and others known to be drought resistant. Anaphalis margaritacea, pearly everlasting,

native to Oregon’s west side and Northeast mountains.

ObjectivesUse appropriate

techniques like mulching and zoning – planting species with similar requirements together for efficiancy.

Include all layers of growth—trees, shrubs, herbaceous plants, and ground cover.

A tub containing herbs and marigolds is a form of zoning.

Management - Plant Choice -

Choosing the right plants is key to creating a Waterwise garden.

Example is a Spanish lavender from the Mediterranean.

Management - Plant Choice -

Plants native to Oregon

Plants native to Mediteranean climates

Selected succulentsHerbsBulbsNorth American trees

and prairie plantsOthers that are

drought-hardy

Linum sp., blue flax

Plants Native to Oregon

Usually incorporates native plants considered to be “garden-worthy”.

Focuses on native prairie plants and flowering shrubs.

Avoids or limits moist woodland plants, wetland plants, or those requiring special conditions for growth.

Fall color--Ribes aureum, golden currant, native to Oregon’s eastside.

How to I Know the Distribution?

I consult the Oregon Flora Project, housed at Oregon State University. This site provides correct and current scientific names, generates maps of plant distribution, has a photo database.

Ribes aureum var. aureum

www.oregonflora.org

More Native Plants “Native” of course

depends on where you are from if you want to use only local natives.

Amelanchier alnifolia, service berry, native to many regions on Oregon’s westside and some regions on Oregon’s eastside. Different varieties are found on different sides of the Cascade Mountains.

More Native Plants - Trees

Choices include many native trees.

Trees provide shade, shelter, wildlife food and garden interest.

Arbutus menziesii, madrone, restricted to Oregon’s west side.

Rhamnus purshiana, cascara, native to western Oregon and NE mountains

More Native Plants - Shrubs

Flowering shrubs make seasonal counterpoints.

Both flowering and fruit bearing stages provide beneficial wildlife support.

Shrubs are at eye level and a “medium” layer of interest.

Symphoricarpos albus, snowberry, native to Oregon’s west side and mountains on Oregon’s eastside.

Philadelphus lewisii, western mock orange, throughout Oregon, but in generally more moist locations east of the Cascades.

More Native Plants - Perennials

Perennials fit well into borders, both sunny and shady.

Many have brilliant bursts of color.

Perennials add interest and help protect from soil compaction.

Eriophyllum lanatum, Oregon sunshine, grows statewide, but different varieties are found in different portions of the state.

Sidalcea campestris, restricted to Willamette Valley in Oregon.

More Native Plants - Groundcovers

Groundcovers are valuable parts of a landscape.

Groundcovers provide habitat for amphibians and insects.

Groundcovers protect the soil from erosion and compaction.

Viola glabella, stream violet, native to Oregon’s west side and northeast mountains.

Oxalis oregana, wood sorrel, found on Oregon’s west side.

North American Prairie Plants

Plants from prairies of North America are excellent choices for waterwise landscapes, and tend to be noninvasive in Oregon.

Gaillardia species, or blanket flower, can be annual or perennial. One species Gallardia pulchella occurs on Oregon’s eastside.

More Prairie Plants

Sunflowers are bred or selected from annual species of Helianthus annuus, native to NA prairies. Wild Helianthus annuus are found in parts of Oregon. Also shown is Rudbeckia hirta, black-eyed Susan, Helianthus ‘Lemon Queen’ and Echinacea purpurea, purple coneflower.

Other NA Plants, Focus on Trees and

Shrubs

Plants Native to North America show fewer invasive tendencies in Oregon

Many of our standard landscape trees such as sugar maple come from North America

Nyssa sylvatica, sassafras, Eastern North America.

Magnolia grandiflora, southern magnolia, from SE US. Wikipedia.org author: DavetheMage.

Plants from the Mediterranean

Many species of Cistus, or rockrose, shown on right. Santolina, lavendar cotton and dusty miller Jacobaea, shown on the left .

Bulbs Crocus, tulips,

daffodils, and many others.

They survive dry periods by becoming dormant.

Herbs Many are from

Mediterranean regions of the world.

Perennial herbs such as sage, rosemary, and lavender so well in our climate with little supplemental water.

Certain Succulents

Hardy succulents are perfect for the waterwise approach.

Shown here are Echeveria, several native Sedum (S. spathulifolium and S. oreganum), and Sedum ‘Autumn Joy’.

Others

Ginkgo biloba, maidenhair tree, native to China and known from the fossil record in Oregon

See “List of WaterWise Plants at: http://extension.oregonstate.edu/yamhill/eco-gardening/waterwise-gardening or posted online at Slideshare.net

Epilobium canum, California fuschia, a “near-native” perennial for most of Oregon, but found naturally in SW Oregon.

Landscape ExamplesFront Office

Landscape, OSU Extension Service, Yamhill County in McMinnville at 2050 Lafayette Ave NE.

Plants include Campsis radicans vine (native to NA) and Mediterranean plants like lavender, Cistus, and Santolina.

Landscape ExamplesNewberg Library

WaterWise Demonstration. Award-winning garden is in the parking lot as you proceed south on 99W.

Parking islands receive no supplemental irrigation.

Techniques are explained for the public.

Landscape ExamplesMore from Newberg

Library WaterWise Demonstration Garden.

Bryan, shown here, was an OSU Master Gardener who envisioned the project. He is now with Chehalem Parks and Recreation.

Photo: OSU

Extension Service

Landscape ExamplesPrivate Garden in hills

west of McMinnville, OR.

Relatively “young” garden also designed to be deer-resistant.

Includes some natives but relies heavily on plants from the Mediterranean.

Landscape ExamplesPrivate Garden in

McMinnville, OR.Recently redesigned

border to be more water efficient.

Includes water-efficient “herb-lawn”, succulents, Oregon iris, and other shrubs and perennial plants.

Landscape Examples

Private garden in Corvallis, OR.

Rental property, so minimal effort desired.

Includes natives and plants of prairie or Mediterranean origin.

Oregon sunshine, Douglas aster, nasturtium, blanketflower, penstemons, Helianthus cultivars.

Management - Irrigation -

Irrigation methods are chosen to reduce water use and be site-specific.

They include hand watering, drip systems, small pop-up sprayers, automated links to weather stations, and soaker hoses.

Irrigation of some kind is necessary for plant establishment in most cases.

Management - Zoning -

Zoning is a practice of grouping plants together depending upon their characteristics, into zones.

Example: plants requiring full sun but minimal water, only in July-September.

Each zone will receive a different water delivery.

A plant pot can be a “zone” for high water use plants.

Management - Water -

Simple things like parking pavers can create a permeable surface to avoid water runoff from a garden.

Other examples include permeable concrete, gravel or bark paths, rain water harvesting, even bioswales or rain gardens.

Parking pavers at the Newberg Library garden.

Management - Other Methods-

Mulch and groundcovers reduce weeding, need for irrigation and protect soil from compaction.

One innovative form of “mulching” is to plant plants very close to each so the cannopy can protect the soil and exclude most of the sunlight to reduce weed growth.

An example from the Newberg Library garden.

Management - Making the Change -

Change practices gradually

rather than all at once. It takes time.

Consider minimizing or eliminating lawn, or using a lawn alternative like an “herb lawn”.

Do research before you begin-hardiness, water and light requirements, etc.

Double check plant list for invasive potential. An example from the Newberg Library

garden.

Resources• Plants. Waterwise list for

Oregon developed by a team and general website at http://extension.oregonstate.edu/yamhill/eco-gardening

• Plants and Methods. Xeriscaping in Central and Eastern Oregon. http://extension.oregonstate.edu/deschutes/sites/default/files/xeri-all_1.pdf

• Plants and Methods. Online noncredit classes at Oregon State University, https://pne.oregonstate.edu/catalog

Know where to go when you need information.

Resources• Plants. Slideshare.net.

Search for presentations and materials by Linda McMahan.

• WaterSense, a Program of the Environmental Protection Agency: http://www.epa.gov/watersense/

• Water Efficient Landscape Booklet, EPA: http://www.epa.gov/WaterSense/docs/water-efficient_landscaping_508.pdf

Know where to go when you need information.

Resources• Brochure City of Portland:

http://www.portlandoregon.gov/water/article/268757

• Website – Water Efficient Plants for the Willamette Valley: http://www.clackamasproviders.org/water-efficient-plants/ note: some plants listed are “moderate use” and may require careful zoning to conserve overall water.

Know where to go when you need information.

Thank youCopyright Linda R. McMahan, Oregon State University Extension Service, 2013. Presentation may be used freely for educational purposes with credit to the author and Oregon State University. Please contact the author for other uses.