Water-Wise Gardening Tips
We are in a period of global-warming, and there is no denying that many parts of the world are struggling with serious water shortages. Here in my state, residents are being asked to cut their usage by 25%, and landscape irrigation is allowed only twice a week. Heavy rain and snow pack will help, but it will take successive years of it to replenish the depleted groundwater that has sustained us through years of drought.
Californians have grown used to the sweeping lawns and lush flower beds that came West with migration and have stayed in fashion ever since even though our climate is better suited for our native plants or at least Mediterranean ones. When driving through any residential neighborhood, you might notice that nearly every home has a sizable patch of green in its front yard. We have managed for nearly a century to sustain these thirsty landscapes until now. Does this mean that verdant yards must be replaced with rocks, mulch or chaparral? Thankfully, NO!
Consider Adjustments To Your Watering Routine
It may surprise you to learn that more plants die from too much water than not enough. Over watering encourages bacterial disease and the proliferation of fungi which naturally live in the soil. This is why we see toadstools and slime molds after rains and why powdery mildew, rust, and black spot show up after dewy mornings and during humid summers. We can't control rainfall, but we can make a difference by changing water timers and adjusting our irrigation delivery.
It has been shown that the best time to run lawn sprinklers is between 4 am and 8 am. This is off-peak time, and the cooler air minimizes evaporation yet the sun will soon be up to dry grass blades and leaves. It's sensible to avoid overhead watering in the evenings because the prolonged moisture on foliage is a main cause of common mildew and other fungal infections. The newer sprinkler heads sit closer to the ground and slowly rotate with an even stream of water making them 30% more water efficient. Even during the hottest months, lawns benefit from less frequent deep watering than from numerous surface waterings. 15-20 min. twice a week is more productive than 5 -10 min. 4 times a week. If water begins to run onto concrete areas, turn off the sprinklers until the water soaks in, then run again a little later. This cycle-watering is good practice for poor drainage and compacted areas affected by drought. Resetting sprinkler timers seasonally and manually turning them off during rains will save both water and money. Better yet, consider a Smart WiFi timer which allows for adjustments when away from home.
Brown patches on lawns are hard to diagnose, even for a nursery professional. What we think of as dry areas are often fungal infections, and watering to fix them actually makes them worse. If the patch continues to grow outward, it is usually disease related. A thirsty lawn area will take on a wilted, bluish tint in heat and can be spot watered as needed. Deep watering promotes healthy roots, and along with other good cultural practices like mulching with lawn clippings and mowing with a sharp blade, will help fend off insects and pathogens. Reducing fertilizer applications in summer will also lower the need for water. Slow release organic feedings improve soil structure and attract earthworms. Rapid growth requires more water and encourages insects. Consider the season. Cool season grasses like dwarf fescue and rye will slow during hot summers. Apply fertilizer in fall. Warm season varieties like Bermuda and St. Augustine begin to go brown as temperatures drop. Give them feedings in spring. Water more when growth peaks. Reduce irrigation when it slows. With a few exceptions, brown lawns indicate dormancy. Most will recover with good seasonal rainfall.
Weeping soaker-hoses, drip emitters, and bubblers are among the best irrigation devices for water-wise gardens. Some existing sprinkler heads can be easily converted. These used in conjunction with mulches will greatly reduce the need for water. Grouping plants with similar water needs together makes for more efficient water management. Selecting native plants when possible and giving new plantings the benefit of cooler seasons to get established will also help. In the West, fall is the best season to add shrubs, natives, and hearty perennials. Elsewhere, spring is best. Well-rooted plants can better withstand the stresses of summer heat. Annual bedding plants do best if started from seed, but those from 6-packs will thrive too if deeply watered during warmer months. I harvest the moisture run-off from my roof. Rain barrel systems are a win-win. Many double as planters and some qualify for rebates in drought-stricken states. Filling a bucket while waiting for shower water to get hot and using it to water container gardens is a good practice. I also use gray bath water for irrigation, and it surprises me how much fresh water I save!
Mulches keep evaporation to a minimum, encourage earthworms, and cool roots. Place them 4-6" away from plant centers.They can be made from cardboard sheets and layers of uncolored newspaper. Other options are straw, wood chips, coir fiber, leaves, and compost.
It takes nitrogen to break down carbon in chunky mulches, so supplemental fertilizer may be needed.
There are so many viable alternatives to thirsty plants and practical ways to handle those favorites which do require more water. Bulbs, rhizomes, and tuberous plants like dahlia, daylily, bearded iris, and agapanthus are nice additions to water-wise gardens as are most woody shrubs and trees. Agave and succulents add beautiful diversity along with flowy ornamental grasses, cordylines, and phormiums. Australian and South African specimens like kangaroo paw, grevillea, and leucodendron give gardens unique touches and that "WOW- factor." Hearty salvia, Jerusalem sage, penstemon, and yarrow are water-smart cottage favorites. Citrus, pomegranate, lavender, and rosemary are just a few among the many Mediterranean specimens suited for drier climates. Consider reducing turf areas with meandering walkways or dry creeks. Expanding flower beds and accenting them with well-placed rocks and attractive ground cover adds lushness without high water need. Birdbaths and garden benches break up visual monotony while adding function. Interspersed container gardens and empty pottery tumbles add even more visual interest and flexibility with ease of movement. Unleash your creativity!
California Native Plants
Native plants are equipped to handle hot, dry summer climates. Most bloom in fall or spring then go dormant when temperatures climb. During these periods of rest, water applications should be minimal at best. Late fall is the best time for planting. I recommend filling the hole with water and letting it drain before dropping in the root ball. I then fill with well-draining soil. California's indigenous selections rarely need amendments or fertilizer but will benefit from occasional deep watering until established.
Ornamental grasses add a flowy look and combine with other shrubs like pittosporum, nandina, and kangaroo paws.
Unique heat-tolerant plants that add that "WOW-factor"Click thumbnail to view full-size
Watering is much easier to control in containers, especially with the use of a moisture meter probe which takes away the guesswork. Beautiful plant combinations can be creatively arranged using the "thriller, filler, and spiller" guideline. As long as the choices have the same water and light needs, you can really have some fun! Pots can be easily moved if needed too. There are so many styles and materials from which to choose. Just make sure there are adequate drainage holes. Should a ceramic pot shatter, save the pieces to incorporate in concrete as mosaic stepping stones for your garden path.
When soil is poor, or there are problems with inadequate penetration or excess water run-off, a raised bed may be the solution. Adapted from the French Intensive style of gardening from the 1800s, these easily accessible beds are filled with loose and friable soil. Plants can be spaced much more closely, so, when mature, they touch. This keep weeds out. Those that do manage to sprout can be easily removed. Raised beds require about 1/2 the water required for traditional gardens. I have a densely planted pollination bed for bees and butterflies. I especially recommend them for root crops and leafy greens.
Suggestions for Healthy Growth
Plants can suffer from root-rot but still perish from dehydration. How? Frequent shallow watering will affect surface roots and weaken them, yet the deeper roots can be bone dry. When in doubt about moisture levels, probe the soil to a depth of 4". If it is dry, water accordingly. Moisture meters are also available on line and in garden centers. In larger areas, a spade works great to to check water penetration. Clay soil will hold water longer than sandy soil which drains quickly. When I plant from a 1 gallon or larger nursery container, I will dig the hole and fill it with water first. Once it has drained, I add my scoop of mycorrhizae to help with rooting and nutrient uptake, then drop in my plant and work in w/ amended back-fill. This tells me about my soil and also gives my plant a boost. Consider too when your plant is actively growing. Water needs will fluctuate with seasonal growth cycles. This is true for both houseplants and outdoor specimens.Water-wise doesn't sacrifice beauty, it just makes us rethink our practices and the elements of our gorgeous garden palettes so we can work with nature and not against it.
© 2016 Catherine Tally