Easy Water-Wise Gardening - San Diego, California

1. Where to get help
Many professionals can help you Favorite websites
design and implement a water- bewaterwise.com Low-water landscape
Easy water-wise
conserving landscape. Before deciding design ideas, irrigation advice, and
on anyone, get several bids and talk links to local water agencies.
with previous clients. ccwater.com/conserve Contra Costa
Local water districts usually offer Water District’s website provides infor-
a wealth of information, including mation on water conservation, land-
gardening
recommended plant lists, watering scape design, and maintenance.
guidelines, and water-saving tips. irrigation.org Information on smart
Landscape architects design entire controllers and efficient irrigation, and
outdoor environments, from plantings tips for hiring an irrigation contractor.
to structures like patios and decks. irrigationessentials.com Information on
Licensed and university-trained, they irrigation equipment and efficient
can provide the whole package, from
design to installation. Or they can help
watering.
www.nrcs.usda.gov Tips for backyard
Advice and design ideas
in specific trouble spots, such as steep
slopes or areas with poor drainage.
conservation.
savingwater.org The Saving Water Part-
for the 21st century.
smart Gardening ideas
Subscribe to Sunset magazine for landscaping inspiration
Landscape contractors are trained
and licensed in methods of earth
nership’s website provides water-
conserving information for the
From the editors of A
and gardening advice tailored to your climate in each
monthly issue. Visit sunset.com or call 800/777-0117. moving, construction, irrigation, and Northwest.
planting. They are very useful for diffi- snwa.org The Southern Nevada Water
cult projects. Authority’s website provides informa-
Landscape or garden designers tion on low-water plants, landscaping,
have varying degrees of education but and irrigation.
are usually not licensed. The focus of sunset.com Sunset’s website offers
their work is likely to be residential landscape ideas, planting plans, and
gardens. Often they work in conjunc- detailed information about local
tion with a landscape contractor. climate zones.
Irrigation consultants are water.ca.gov California Department of
usually licensed contractors associated Water Resources’ website provides
with an irrigation-supply store (another information on drought in California,
good source of information). They can unthirsty plants, and efficient irrigation.
help design and install efficient irriga-
Use these companion books from Sunset to help you tion systems.
garden successfully in your climate zone. Available at Local nurseries can offer useful
your local bookseller and home and garden center. information and assistance in choosing
plants and irrigation equipment. Many
have design services.
Sunset Plant Finder
Looking for the right low-water
plant for your climate and gardening
style? Go to sunset.com/plantfinder
A
Thomas J. Story
and search by type, growing condi-
tions, and color.
Copyright © 2009
Sunset Publishing Corporation
ER-641
32 Sunset Easy Water-Wise Gardening 1

2. Great gardens
for a new era
In the West, water is as precious as
gold. Most of our rainfall comes in winter,
yet many garden plants need irrigation
in summer, during our driest months.
Seasonal droughts, groundwater pollu-
tion, and population growth stress this
valuable resource. If we are to have
enough water in the future, we must
avoid wasting water in our homes and
gardens today.
Of the water Westerners use at home,
about 50 percent goes to gardens. So the
most important place to start a conserva-
tion program is right outside our doors.
Fortunately, water conservation doesn’t
mean settling for a barren landscape; it
means practicing good gardening. Choos-
ing plants well adapted to your climate,
improving your soil, watering efficiently,
and taking advantage of the latest irriga-
tion technology all help save water.
Plants that require less water are
widely available at nurseries. The Sunset
Western Garden Book, Sunset Western Land-
scaping, and the online Sunset Plant Finder
tool (sunset.com/plantfinder) can provide
you with lists and plans.
In this booklet, we offer many ways to
save water in your garden, including
watering strategies based on soil type,
smart use of watering devices, and advice
about selecting an efficient irrigation
system for your garden.
Contents
A gorgeous mix of 4 Low-water landscape design
low-water plants, Elements of a dry garden, plants
including California
fescue, carex, catmint,
for all climates, planting plans,
erigeron, ‘Garnet’ permeable surfaces
penstemon, lavender, 4
1 Efficient irrigation
Mexican bush sage,
‘Morning Light’
Manual watering, sprinklers, drip
miscanthus, and systems, choosing the right system
rosemary. 6
2 Water savings
Mulch basics, rainwater harvesting,
putting it all together
2
3 Where to get help
Saxon Holt
Professionals to consult and websites
to browse
2 Sunset Easy Water-Wise Gardening 3

3. Design
Elements of 8 Water-saving
basics
5. Upgrade your
irrigation system Add
a low-water
Follow these guidelines for elements such as smart
a water-efficient garden controllers connected to
1. IMPROVE THE SOIL weather stations and
landscape Routinely cultivate the
soil in your vegetable and
annual beds, incorporat-
new, highly efficient
sprinklers or drip emitters
to make precision water-
A dry garden can be as ing organic matter such ing much easier. (See
inviting as any other as compost. Doing so
improves the soil’s ability
pages 16–21.)
6. WATER DEEPLY Irrigate
Drought is a fact of life in the West. to retain moisture. Most established plants thor-
landscape plants (trees, oughly but infrequently
It’s part of the natural weather cycle.
shrubs, and native plants to encourage roots to
That's why water conser­vation should be a especially) establish grow downward; they will
part of every Westerner’s lifestyle. Happily, faster when planted in be buffered from the wet-
a well-designed water-wise land­scape can native soils without the dry cycle typical of the
addition of amendments. upper soil area and may
be lush and colorful and will make your
If your soil is sandy or tap into groundwater.
home a beautiful and inviting place. rocky, you may need to 7. IRRIGATE EFFI-
Start by leaving more areas unplanted add compost. CIENTLY Make sure your
than you would if you lived in a wetter 2. plant in the right watering practices and
place Locate unthirsty devices are as efficient as
climate—a big water savings right off the possible. Water plants
plants where they’ll get
top. Make the paths generous and put the sun (or shade) expo- only when needed, not by
gravel under seating areas instead of sure and soil drainage the calendar or clock.
planting a groundcover. Use decomposed they need. Group plants Water at night, when
that have similar water evaporation is much
granite in place of thirsty lawn grass. Then lower and the air gener-
needs so none gets too
plant the remaining spaces with ornamen- little or too much water. ally calmer. Tighten
tals that are adapted to arid climates. 3. Shrink the lawn faucets so they don’t
Finally, to highlight water’s revered status Most lawn grasses need leak. Avoid runoff and
enormous amounts of wasteful overspray.
in the unthirsty garden, add a few traces water to stay green and 8. MULCH Cover bare
of it, some real, some illusory: a fountain lush. Reduce your lawn’s ground around each plant
that barely trickles, a dry streambed that size, or—unless you need with a 3-inch layer of
it for kids to play on— mulch to help conserve
awaits the next downpour, or a lovely urn.
eliminate it altogether. soil moisture, suppress
4. CONTROL WEEDS weeds, and keep the soil
These garden intruders cooler; renew annually.
steal water needed by Organic types such as
desirable plants. Regu- bark chips, shredded
larly hoe or pull them out bark, or compost improve
when they’re young, or the soil as they break
use landscape fabrics and down, and encourage
mulches to discourage beneficial microbes. (See
growth. pages 26–27.)
No lawn Drip irrigation Permeable paving Xeric plants Mulch
Using a tapestry of groundcovers Low-flow irrigation is the most Strips of elfin thyme and Armeria Native and Mediterranean plants, A thick layer of mulch helps preserve
instead of thirsty turf to landscape efficient way to water plants— maritima dissect the flagstone paving such as the manzanita, yarrow, soil moisture. But it can also enhance
Steven A. Gunther
the front yard saves precious water. there’s no runoff or evaporation. leading to the front door, soaking up Euphorbia, and Kniphofia pictured, design, creating negative space that
design Jeffrey Gordon Smith It’s also the healthiest system for rainfall and directing excess to the are well adapted to the West: They makes plant groupings or individual
Landscape Architecture, Los Osos, plants because the water penetrates yard on either side. require little water and maintenance, specimens stand out.
CA (jgsdesigns.com) deeply into the soil, encouraging and their blue-green, gray-green
plant roots to do the same. foliage looks right in our light.
4 Sunset Easy Water-Wise Gardening 5

4. Design
5 great
water-wise
details
Low water,
1. BRIGHT COLORS
Yellow columbine, red
valerian, and lavender
high style catmint bloom amid a sea
of mown buffalo grass in
a New Mexico garden. A
Combine flowering and cluster of aspen trees
provides light shade for
foliage plants for a colorful, the columbine.
all-season garden 2. FOLIAGE TEXTURE
Strong architectural
Water-thrifty gardens deliver all the details set the stage for
bold forms and colors of traditional land- this Seattle garden filled
scapes, but with minimal resources and a with billowy grasses and
lot less effort. As with any garden, they perennials. Along the
gravel path, giant feather
incorporate all the elements necessary for grass (Stipa gigantea) and
outdoor living and entertaining: Paths and maiden grass create
patios to give the garden form and direc- clouds of strappy foliage
tion. Arbors and trellises to help divide the beside catnip and Span-
garden into rooms, and to create shade.
Benches and outdoor furnishings for
ish lavender.
3. BOLD SHAPES Golden
barrel cactus appear to
2 3
comfort. But that’s where the similarity to march along the top of a
rock wall between fine-
conventional landscapes ends.
textured purple Dalea
The gardens pictured here are designed greggii plants. An Agave
to thrive on little more than rainfall, but weberi adds drama behind
they offer many other advantages beyond them, while blue palo
verde and desert iron-
conserving moisture. Drought-tolerant wood trees soften the
plants don’t require much, if any, fertilizer, house walls.
clockwise from top left: saxon holt, andrew drake, d.a. horchner/design workshop, bob wigand, saxon holt
so they tend to grow at a rate that’s easy 4. LUSH PLANTINGS In a
to manage without constant pruning. San Diego garden, a
dense border on a slope is
Because they produce less green waste, filled with large native
they contribute less to landfills. In addi- boulders. From the front
tion, many drought-tolerant plants, espe- are bright green aeonium,
cially Western natives, attract birds and yellow pincushion
(Leucospermum), yellow
butterflies, which come to dine on insect
pests or to sip nectar.
Cotula coronopifolia, varie-
gated Furcraea foetida 1
It’s possible to have a garden that’s ‘Mediopicta’, and a red-
both water-conserving and beautiful, with flowering ivy geranium.
5. TWIST ON TRADITION
plenty of lush foliage and a generous dose A suburban front yard in
of seasonal flowers. All of the gardens Long Beach, CA, planted
pictured are rich tapestries of color and with dark green Carex
pansa, is watered only
motion, thanks to their diverse palettes of
once a week in summer
carefully chosen natives, perennials, orna- and mowed just four
mental grasses, shrubs, or succulents. times a year.
Water-wise gardens take a bit more
planning than ordinary landscapes, but
over time they offer significant savings in
labor costs—and, of course, water.
5 4
6 Sunset Easy Water-Wise Gardening 7

5. Design
Plants for 7 great
water-wise
all climates
plantings
1. LOW SPREADING Cean-
othus griseus ‘Kurt Zadnik’
Choose ornamentals that is a colorful groundcover
that grows 2 to 3 feet tall
thrive in your region and 6 feet wide or more.
Spring flowers are deep
While local natives are best suited to blue.
most sites, other good choices include 2. WATER-WISE AND
drought-tolerant plants from all corners of FIRE-WISE In a San
2 3
the world. Some of the most water-wise Diego–area garden,
spaces between boulders
options are native to the Southwest are filled with a deep pink
deserts. Others are from the five Mediter- rose-scented geranium,
ranean climate regions—California, the white nutmeg-scented
Mediterranean basin, South Africa, south- geranium, and purple
sweet-pea shrub.
western Australia, and the central coast of 3. wildlife magnet
Chile—where rains are spare and summers Coneflower (Echinacea) is
are warm and dry. a tough perennial with
Many of these plants share characteris- daisy-like flowers in pink,
lavender-purple, yellow,
tics that help them survive periods of orange, and white. Bees
intense heat and low rainfall. They may and butterflies love to
have gray or velvety leaves that reflect visit the beehive-shaped
centers for nectar; finches
heat; succulent leaves, stems, and roots
visit later for seeds.
that store water; or needlelike leaves 4. EASY TO GROW Horned
whose small surface area limits the poten- poppy (Glaucium flavum)
tial for water loss. Or they may go dormant produces rosettes of crin-
kly gray-green leaves
during the hottest months of the year. topped by orange to
Water-wise plants have different bright yellow blooms.
degrees of drought tolerance. Plants that 5. BRIGHT BERRIES Tall
(usually to 10 feet), dense
clockwise from top left: bob wigand (2), Steven A. Gunther, bob wigand (3), jim mccausland
thrive on 30 inches of rain in the Northwest,
Toyon puts on a bright
for instance, will wither in a Southwest show in winter, when red
garden where the average rainfall is 10
inches or less. Do your homework before
berries envelop the shrub.
6. BOLD FOLIAGE Clouds
of lime-colored flowers
1 4
finalizing plant choices, then group plants
on Euphorbia characias
into zones by their water needs. Place wulfenii contrast with
thirstier (and often showier) plants near- chocolate-hued Aeonium
est the house or in other high-visibility arboreum ‘Zwartkop’ to
spots, less thirsty plants in the background. create drama in a San
Clemente, CA, garden.
Make sure your irrigation plan supports 7. SHAPE AND TEXTURE
each zone independently of the others. Mediterranean-climate
Avoid the mistake of thinking that some plants fill a garden border
in a rain shadow along
types of plants never need watering. All
Washington’s Puget
plants, native or not, need regular, deep Sound. They include Aster
irrigations through the first year to help ‘Mönch’ and Schizostylis
their roots become established. Some need coccinea ‘Oregon Sunset’,
framed against ‘Gold
moisture into the second year, but by then, Sword’ New Zealand flax.
many do fine with only an occasional deep Behind is tall, airy Verbena
watering. A bit of research and consulting bonariensis.
with your local nursery or cooperative
7 6 5
extension service will help you figure out
how much water your plants need.
8 Sunset Easy Water-Wise Gardening 9

6. Design
Low-water
planting plans
E f
g
Brighten a garden bed with D
herbs for your kitchen or i
b
berries and flowers for birds a
The best plants for low-water gardens
h c j
not only enliven the landscape and thrive
on little water once established, they have
Chives Lemon thyme
other benefits as well. Woody perennial Planting area: 8' x 6'
herbs such as rosemary, sage, and
thyme—all native to the Mediterranean Pocket-size herb sampler Plant list
region—produce leaves that can be used Just 48 square feet is space enough for a diverse assortment of A. Chives (Allium F. Rose (‘Sunsprite’); 1
fresh or dried to flavor meat, soups, and scented herbs plus a compatible fragrant rose. Seven of the nine schoenoprasum); 3 G. Rosemary (Rosmari-
B. French tarragon nus officinalis); 1
stews. In beds and borders, they combine herbs have culinary uses, making this planting especially appeal- (Artemisia H. Common sage
well with blooming perennials such as ing to cooks (particularly if it’s located near a kitchen door). The dracunculus); 4 (Salvia officinalis
blue-flowered catmint and sunny yellow two nonculinary choices—lavender cotton and catmint—add to C. Catmint (Nepeta x ‘Icterina’); 1
patio roses. the plot’s beauty with their soft textures and equally soft gray- faassenii); 3 I. Lavender cotton
D. Sweet marjoram (Santolina chamaecypa-
Unthirsty shrubs and perennials that green to gray-white leaf color. In fact, much of this garden’s (Origanum majorana, rissus ‘Nana’); 3
pump out flowers, berries, or seeds invite charm derives from its varied foliage colors and textures; conspic- Majorana hortensis); 1 J. Lemon thyme
all kinds of birds to your garden, bringing it uous flowers appear chiefly on the chives, catmint, lavender E. Oregano (Origanum (Thymus x citriodorus)
Catmint Common sage vulgare); 2 ‘Aureus’; 1
alive with beauty and motion. (Birds also cotton, rosemary, and rose.
feast on pest insects.)
You can re-create one of the borders
pictured at right in your own garden. The
best time to plant is early fall, before rains
opposite, clockwise from top left: david cavagnaro, thomas j. story (3), ben woolsey, claire curran,
come (they’ll help irrigate the new trans- c b
plants for free). Locate both beds in full a
sun. The bright herb sampler is designed h
to fit a small (8- by 6 -foot) space. The f g
birdscape is backed with three billowy f
norman a. plate (2); illustrations, from top: lois lovejoy (2), erin o’toole (2)
shrubs that need more room to sprawl. e i
The total number of each plant needed d
is indicated after each plant in the “Plant g
c
Lists,” far right.
Blanket flower Black-eyed Susan Planting area: 25' x 18'
Western birdscape Plant list
This small planting design is suited to mild-winter areas of Cali- A. Elaeagnus x F. Black-eyed Susan
ebbingei; 1 (Rudbeckia fulgida sulli-
fornia and the Southwest deserts. Though it lacks trees and a B. Firethorn (Pyracan- vantii ‘Goldsturm’); 11
watering hole, it offers most of the inducements that birds crave: tha coccinea ‘Kasan’; 1 G. Fountain grass
berries, seeds, and shelter. The irresistible lure—as legions of C. Lantana (Pennisetum
gardeners have come to know—is the yearly crop of firethorn ‘Radiation’; 3+ setaceum); 6
D. Heavenly H. Blanket flower
berries, but the garden’s feathered patrons will also feast on the bamboo (Nandina (Gaillardia x grandi-
fruits of lantana, heavenly bamboo, cotoneaster, and Elaeagnus. domestica); 2 flora); 5
Seed-eaters will appreciate the bounty of coreopsis, blanket E. Willowleaf coto- I. Coreopsis grandiflora
flower, black-eyed Susan, and fountain grass. The shrubs all neaster (Cotoneaster ‘Sunburst’; 4
salicifolius ‘Emerald
Fountain grass Firethorn afford ample shelter. Carpet’); 2+
10 Sunset Easy Water-Wise Gardening 11

7. Design
Permeable 7 ways to use
porous paving
surfaces
1. golden gravel In
this Los Angeles garden,
a base of warm-toned
Let rainfall percolate down 3/4-inch gravel makes a
bold visual distinction
to plant roots from surrounding green-
ery, including drought-
Paths and patios that are paved with tolerant blue Senecio
gravel, decomposed granite, spaced flag- mandraliscae.
stones, or porous concrete are the best 2. shale and pavers
2 3
choices for water-conserving gardens. Fractured shale fills gaps
between concrete pavers
Permeable paving materials add beauty in a garden in Alamo, CA;
and structure to the garden and, of course, yarrow and grasses
require no irrigation themselves. More- soften path’s edges,
over, they allow rainwater and irrigation to 3. classic filler
Drought-tolerant creep-
pass through them and into the soil, ing thyme grows 3 inches
preventing runoff that can clog storm tall and roots as it spreads
drains and pollute nearby lakes, streams, to fill spaces between
and coastal waters. flagstone pavers.
4. woodsy path Spaced
If you’re considering gravel, visit your concrete “stones” curve
local landscape supply yard to experience through a garden in Gig
the look and feel of different types. Gravel Harbor, WA.
5. fit for a fireside
refers to rocks ranging in size from 1/8 inch
‘Paprika’ yarrow and
to 11/2 inches. It comes in two forms: ‘Walker’s Low’ catmint
Manmade crushed rock has sharp, irregu- edge a secluded gravel
lar edges; nature-made river rock (also seating area in Califor-
nia’s wine country.
known as natural pebbles) is rounded. 6. paired materials
Think about where it will be used. For Edged with pale flag-
high-traffic areas, such as paths and stone, a half-inch of
patios, use manmade crushed rock. decomposed granite over
a compacted base forms
Because the pieces bind together well, a well-draining surface in
they create a more stable surface for walk-
ing. The most common size is 3/8 inch, an
this garden in Rancho
Mirage, CA. Palo verde,
agaves, opuntia cactus,
1 4
all-purpose gravel that’s also good as a
and barrel cactus thrive
mulch around plantings. For a softer in the flanking gravel
surface under bare feet, use 1/4-inch or patches.
finer natural pebbles. For low-traffic areas, 7. Pocket patio A 7-foot
Clockwise from top left: Steven A. Gunther, Thomas J. Story,
river rock is an attractive choice, but the circle of bricks set into a
base of compacted sand
larger, smoother pieces are less stable is easy to move and adapt
Thomas J. Story, Steven A. Gunther, Thomas J. Story
underfoot than crushed rock. for different purposes.
jennifer cheung/Jupiter Images, jimmccausland,
You can green up surfaces covered with
stone or cobbles by planting mat-forming
groundcovers between the pavers. Good
choices for this use include creeping thyme
(shown at far upper right); Dymondia
margaretae, which forms a tight mat of
narrow, gray-green leaves and tiny yellow
flowers in summer; and snow-in-summer
(Cerastium tomentosum), a dense, tufty mat
7 6 5
of silvery gray foliage with small white
flowers in early summer.
12 Sunset Easy Water-Wise Gardening 13

8. Irrigation
Efficient
watering 101
Learn about your soil,
watch your plants, and get
the right tools
When determining how you should
water, first consider your plants. Because How to choose
plants with deeper roots are better able to the right hose
withstand periods of drought, your goal A cheap hose prone to kinks and cracks makes
should be to apply enough water to wet gardening a chore. It pays to invest in quality.
the entire root zone and to encourage nHoses may be made of rubber or vinyl or a
deep rooting. Shallow watering leads to combination of the two. The best models incor-
porate multiple layers of reinforcing fabric such
shallow roots and plants that are very as nylon or rayon. Hose couplings and swivels are
susceptible to drought and fluctuating
temperatures. You should also avoid 1 another indication of quality. The strongest
couplings are made of brass—the thicker the
better—and the best swivels are hexagonal for
applying so much water that it penetrates
easy gripping. Also look for a protective collar just
deeper than roots actually grow. That below the coupling; it’s designed to prevent the
water is wasted. hose from kinking at the faucet.
n Garden hoses vary in length (25, 50, and 100
Watering checklist feet) and diameter (1/2, 5/8, and 3/4 inch). A 1/2-inch
Hydrozoning. Organize your landscape hose can deliver about a third as much water as a
3/4-inch hose. If you have low water pressure or if
into “hydrozones”—groups of plants with you must run your hose uphill, buy the shortest,
similar water, soil, and exposure needs. By largest-diameter hose that’s practical for your
doing so, it’s possible to apply water very situation.
CLOCKWISE FROM TOP LEFT: Thomas J. Story, craig d. wood, Norman A. Plate, Thomas J. Story, darrow m. watt
efficiently and allocate more water to
thirsty plants and less to unthirsty ones. use a hose in furrows
1. Basins 3 to 6 inches deep hold water around
For example, you should separate low- plants. On level ground, link basins to make
water users, which thrive on rainfall alone watering easier.
or with minimal supplemental water (such 2. Furrows 3 to 8 inches deep help a hose-end
as native plants, or ones similarly adapted bubbler attachment irrigate straight rows.
to drought) from high-water users (such
as lawns, annual flowers, and vegetable
gardens). As much as possible, maximize 1
2 3
the amount of garden space dedicated to
low-water users.
Observe your plants. Get to know the
signs of moisture stress, such as droopy, manual watering devices penetrating, push a stiff metal rod into the water until puddles appear, stop until the 1
off-colored foliage. Hand watering can be very efficient: You can pinpoint individual plants and vary watering times based soil after watering. It will move easily water is absorbed, then repeat the cycle
Know your soil. Examine it frequently, on plant needs and weather. The right devices make it easier. through wet soil but will stop or be harder until water penetrates to the desired
making sure it is not too wet or too dry 1. Portable sprinklers 2. Soaker hoses Flat hoses 3. Hose-end nozzles to push when it hits dry soil. Before water- depth. Use drip or low-volume irrigation
between waterings. If necessary, add They feature different spray perforated on one side or Nozzles turn water flow into a ing again, let the top few inches of soil dry (see pages 18–21).
methods: oscillating, rotating, porous “ooze” types work best variety of sprays, from strong
organic matter to new planting areas to impulse, or traveling. Choose a on level ground. Run them jet to gentle mist. Those with
out, depending on the size of the plant. Adjust watering schedules with the
improve soil texture or to hold moisture heavy-weight model with a along rows of vegetables, long handles are especially Avoid runoff. Don’t apply water faster weather and seasons. Water less often in
better. pattern that matches the
shape of the area to be watered
flowers, or hedges; spiral
around trees; or use to
helpful for watering hanging
baskets. (If the nozzle doesn’t
than the soil can absorb it. Direct water to cool weather, more frequently during hot 2
Water deeply, then let the soil partially plant roots by building basins or furrows of weather. Irrigate early in the morning,
and that applies water evenly moisten beds of seedlings. already have a shutoff valve,
dry before watering again. Irrigate long over the entire area. you can connect one between
soil around plants. Use terraces or basins when winds are calm and evaporation is
enough to wet the entire root zone. it and the hose.) to avoid runoff on slopes. Pulse-­irrigate low. (See “How season affects watering,”
To determine how deep the water is plants in clay soil or on slopes: Apply page 25.)
14 Sunset Easy Water-Wise Gardening 15

9. Irrigation
Isolate sprays. Position sprinklers to elements of a
prevent overspray into neighboring
hydrozones or paved areas.
sprinkler system Hose bibb
Efficient Simplify the course. Plot layout of under- System
watering:
ground pipes with fewest turns. shutoff
Control valve and
valve
backflow preventer
with sprinklers Group by valve. Plot circuits—a group of Nozzle
sprinklers controlled by the same valve—
to correspond to the hydrozones. Every-
A good choice for overhead thing on one circuit (valve) will be watered
Schedule 80 riser
irrigation of a large area at the same time. Your water pressure and
For large lawns and some vegetable flow rate will determine how many sprin- Pop-up sprinkler Sprinkler
and flower beds, underground sprinkler klers you can have on each circuit. Each head
systems are a good option. To operate circuit should comprise the same type of
properly, they need high pressure (40 psi sprinklers: spray or rotor. Don’t mix the two.
or more at the water source). You may Cutoff riser
want to hire a professional to plan and Maintain your PVC slip by
install the system, which entails much sprinkler system PVC slip by thread T
Swing joint
thread elbow
physical labor. However, sprinkler manu- To make sure your system operates effi-
PVC pipe
facturers provide good instructions, ciently, often watch it run to check for
and many people decide to do the job signs of leaks, malfunctions, or poor
themselves. performance. Adjust sprinklers when Use the right components Nozzles These determine a sprinkler head’s
necessary, and unclog heads with a knife Control valves These include backflow (anti­ pattern of spray, radius of throw, and amount
Design your system or piece of wire. Replace broken sprinklers
siphon) devices to prevent water from flowing
into the home water supply.
of water delivered. Choose the pattern carefully
to fit the shape of the area. Most spray heads
To design an underground irrigation or risers. Water-filled valve boxes or leak- Tip: Valves are usually grouped together so they have nozzles that emit water proportionately:
system, follow these steps: Sprinkler
ing sprinklers may be a sign that valves can easily be wired to electronic controllers. a 90° nozzle delivers a quarter of the water a
Make a scale drawing of your property. need to be repaired or replaced. Wet spots Pipes These are made of rigid, white polyvinyl full-circle nozzle delivers. Variable-arc nozzles
chloride (PVC). To glue or thread sections of pipe (pictured below) can be adjusted from 0° to 360°
Include new or existing landscaping, hard- and a constantly running water meter are together, you’ll need fittings that come in various of spray; nozzles are also available for small areas
scaping like paths and patios, and any other signs of problems. In freezing configurations (including T and elbow) and types and irregular shapes. All rotors have adjustable
existing underground utilities. Divide your climates, install a drain valve at the (slip and threaded). arcs, although how you make the adjustment
Risers These vertical pieces of pipe connect varies by model and manufacturer.
property into hydrozones. lowest point in each circuit. Before winter
sprinklers to underground pipes. They may be Tip: Easy-to-change nozzles adjust application
Spray overlap
freeze, drain the system through the drain 12 to 18 inches tall to clear shrubs, 6 inches or less rates between heads with different arcs.
Visit an irrigation supplier. Take time valve, and hire a professional to blow for lawn sprinklers.
to familiarize yourself with components compressed air through the system to Tip: You can buy adjustable polyethylene risers
at the desired height, as well as cutoff types that Variable-
listed and shown in the photograph on the clear remaining water. arc
allow a choice of heights. (A swing joint makes it
facing page. Pay attention to sprinkler easy to adjust the height and angle of sprinkler nozzle
output rates and nozzle spray patterns. heads.) A simple twist
changes the
CLOCKWISE FROM TOP LEFT: GEORGE OLSON, THOMAS J. STORY, EM AHART (2)
Sprinkler heads There are two basic catego-
spray pattern
Sketch your system ries: spray and rotary (rotors). Spray heads emit a
fixed spray, whereas rotors—both gear-driven of a variable-
Stores or nurseries that specialize in irriga- Sprinkler and impact types—move as they shoot out single arc nozzle to
tion supplies can help you plan and draw coverage Nozzle or multiple streams of water. Spray heads are the desired
This illustration spray generally for smaller areas, throwing water in segment of
an irrigation system, or you may prefer to patterns a circle.
shows how to about a 15-foot radius. Rotors cover up to about a
have a professional do the design. Regard- position sprin- For proper
45-foot radius but need more pressure to operate.
less, it makes sense to be involved with coverage, 90° 120°
klers to ensure Because they apply water at a slower rate than
even coverage. typically you
the design process. Here are some basic must set some
spray heads, rotors must run for longer periods
Sprinkler heads to wet an area, but they are less likely to cause
tips when planning a system. nozzles to
in the corners runoff.
cast water in an different arcs
Tip: Both spray heads and rotors are available in
Limit heads. Use as few sprinklers as arc, while the than others. 180° 240°
stationary sprinklers and pop-ups.
possible to achieve head-to-head cover- center head
waters in a
age: Spray from one sprinkler should reach
circle. Dark tint
the head of the next sprinkler. For full indicates water
coverage, each area should be covered by overlap. 270° 360°
three sprinklers.
16 Sunset Easy Water-Wise Gardening 17