WHEN IT COMES TO WATERING;LESS IS MORE

Allison Marr

Challenges for the Gulf Island Gardener

Ever burgeoning deer and rabbit population, raccoonsConsiderably higher cost of landscaping materials from plants to soil, mulch and gravelSelection of materials less than off-islandWATER! - low supply, expensive, sometimes toxic

California North?

Local summers are trending hotter and dryerGlobal Warming? What will the effects be on local precipitation rates and water supplies?Coastal BC's annual precipitation rates are still the highest in Canada

Plants

What do we want/need to grow, where and why?

Assess the Site

Assess water supply and availability

Assess availability of time/budget for maintenanceCreate a planProper site selection for landscape elementsPlant selectionProper bed preparation/ drainage/soils

Execution of a New Landscape

Excavating, landscape layout, create bare planting areas and rough-in features, drainageIrrigation installation, electrical rough in – lighting, power supply for ponds & etc.Hardscaping (patios, pathways, decks, fencing)Install softscaping (soils, plants, sod, mulch)Maintain with appropriate cultural methods

Fundamentals of Water Conservation in the Landscape

Work within the water budget of the property/community Use water efficiently to ensure more water is available for the community

Collect water from run-off sources (gutters, roofs, natural ponds, grey water)Water restriction – in place in many communities to safeguard supply

METHODS FOR REDUCING THE WATER DEMANDS OF YOUR GARDEN AND LANDSCAPE

#1. Appropriate plant selection for your site and its environmental conditionsPoor plant selection leads to plants being over or under wateredDisease and pests are more prevalent when a plant is unsuited to its sitePlants under perform in the production of fruit, flowers and new growthWorst case scenario, the plant dies

Choose your plants for the conditions

Condition Ideal Plant Choice Poor Plant Choice

Shade Hosta, Fatsia japonica, Begonia

Lily, Most vegetables, Raspberry

Exposed - Windy Ceanothus, Pine, Hemlock Rhododendrons, Delphiniums

Wet Willows, Ligularia Magnolia, Yucca, Cistus,

Dry Phormium, Lavender, Lavatera Juncus (Rush), Scotch Moss

Full Sun Roses, Dahlias, Prunus Hosta, Maidenhair Fern

Drought Tolerant Plants

The best application for conserving water is selecting drought tolerant plant materialThere is a significant number of drought resistant plants available in our areaThere is often a correlation between drought tolerant and deer and rabbit resistant species

Drought Tolerant Plants in the Landscape

Whenever possible drought tolerant plants should not be mixed with water needy plants in general, but particularly when water conservation is the primary objectivePlacement of dry plants with wet plants defeats the purpose of using drought tolerant species where irrigation is covering both plant types equally

Plant TypesScientific Name Common Name Plant TypeAgastache Tender perennial/annual

Narcissus* Daffodil Bulb

Eschscholizia california California Poppy Perennial/Annual

Artemsia* Dusty Millers Perennial/Sub-shrub

Senecio* Perennial/Sub-shrub

Rosemarinus* Perennial/Sub-shrub

Lavandula* Lavender Perennial/Sub-shrub

Santolina* Perennial/Sub-shrub

Perovskia astriplicafolia* Russian Sage Perennial/Sub-shrub

Centranthis ruber* Red Valerian Perennial

Iris germanica*- Bearded Iris Perennial (Rhizome)

Euphorbia* Perennial

Yucca*- Grass

Cortaderia* Pampas Grass Grass

Pennisetum* Fountain Grass Grass

Stipa* Grass

Ceanothus*- California Lilac Evergreen Shrub

Scientific Name Common Name Plant TypeFremontodendron* Flannel Bush Shrub

Osmanthus* Shrub

Tamarix* Shrub

Berberis* Barberry Shrub

Rubus Blackberry Shrub/Creeper

Juniper* Shrub/Tree

Pinus* Pine Shrub/Tree

Cedrus* True Cedar Tree

Magnolia grandiflora*

Evergreen Magnolia

Tree

Eucaplyptus* Tree

Arbutus menzezii Madrone/Arbutus Tree & Shrub Form

Quercus* Oak Tree

Robinia Locust Tree

Wisteria Vine

Actostaphylos uva-ursi*-

Kinnickinnick Ground Cover

Thymus* Thyme Herb/Ground Cover

Gaultheria shallon* Salal Shrub/Ground Cover

Planting Schedule for Optimum Success and Water EfficiencyIdeal planting /transplanting time is late fall from Mid-October to Mid-NovemberBenefits:• no heat or drought stress on new

plants (especially large trees)• deciduous plants are bare twig and

require little water• precipitation provides water supply

until May• roots develop over winter while the

plants top growth is dormant• plants will need less water

throughout their first growing season

#2 Good Quality Soil and Mulches

Soil type and quality is an important component of a water wise garden• a soil that can be described at loam is ideal• loam is a comprised of slit, sand and clay• clay soils should have organic

matter and sand amendments• sandy soil should have organic

matter added• soils need to breathe and drain

(sand) but also retain water (clay) and provide nutrients to the plant (silt)

Soil Depth

Soil depth depends on what is being grown and where• Raised bed depth is typically 12-24”• Garden beds might range from 6-24”

of topsoil• Lawn/sod areas 4-6”

Mulches

Good quality garden mulch provides excellent water retention and nutrients supplyOrganic mulches keep soil temperatures down and slow down water loss through surface evaporationMulches comprised of garden kitchen, steer, fish, mushroom and leaf compost, seaweed and similar materials are excellentThese materials mixed with fine dark bark mulch make very good mulchesBark mulch on its own is a poor mulch (robs nitrogen from soil, too acidic for many plants)

#3 Cultural Practices

Good cultural practices begin with good site planning and plant selection, good soils and mulchesA simple cultural method that will increase water retention and distribution is cultivating soils/mulches a few times a yearCultivating is simply aerating the top layer(s) of soil/mulch to prevent compactionCompacted soil and mulch are less permeable to precipitation as water, especially on slopes will run off the surface and be wastedCultivation in also beneficial for plant root development and for the absorption of nutrients and minerals

#4 Irrigation Methods

Creating a new landscape or renovating an existing garden should always include a plan for irrigationWhy invest in plant material without a plan to irrigate your investmentCriteria for choosing the best irrigation type are:• water supply• types of plant• size of the landscape project• topography/existing hardscaping• budget

Irrigation Professionals

Choose a certified and experienced irrigation installer/contractor• To ensure your water supply is used prudently

and cost effectively• To ensure quality products and efficient (not

leaking) installation methods are used• For continued service and maintenance

Lawn Rotors

Incorrect Use of a Lawn Rotor

Shrub Sprays

MP Rotators – Very efficient nozzles

Micro Sprays

Drip

WHEN IT COMES TO WATERING;LESS IS MORE

Allison Marr