Landscaping with Drought Tolerant Plants

Saturday, August 8th, 2015 by Jenny Watts
    • Tree collards make a delicious winter vegetable. Set plants out now to give them time to grow before the winter chill that makes the leaves so sweet.
    • Trim grapevines to allow more sun to reach the fruit and sweeten the grapes, if they are being shaded heavily by the foliage.
    • Sow lettuce seeds now for a fall crop. Set out broccoli, kale and cabbage plants too.
    • Feed fuchsias, begonias, summer annuals and container plants to keep them green and blooming right up until frost.
    • Take care of your roses: feed, water, weed, mulch and remove faded blooms regularly. Spray if necessary at first sign of insect or disease problems.

Drought Tolerant Plants

What makes a plant drought tolerant? How soon after planting will it be able to survive on its own? In our dry California climate, understanding drought tolerance is an important part of designing a landscape, and never more important than now.

A drought-tolerant plant is a plant that can survive with little or no water other than available rainfall. Varying locations and soil types affect drought tolerance, and different plants vary in their ability to withstand drought. Whether a plant is in full sun or in some shade will often make a difference as to whether it will be able to withstand drought.

Drought-tolerant plants are able to cope with scarcity of water in various ways. Some plants, including many trees, survive dry conditions with the aid of large, deep root systems that tap water stored deep in the soil. Once they have sent their roots down deep and wide, they will need little or no artificial irrigation. Cedar trees, pineapple guava, olive, oaks and ornamental pistachio trees have deep root systems to survive in dry landscapes.

Many plants have developed leaves which resist drought conditions. Some have developed thick, leathery leaves that reduce water loss. Toyon, manzanita, madrone, wild lilac and oleander are some examples.

Others have succulent leaves that store water and are waxy to prevent water loss. These include Sedums and Sempervivums. Sedums come in many forms from groundcovers, like the blue-green-leaved ‘Cape Blanco’ and golden ‘Angelina’ to the tall ‘Autumn Joy,’ which blooms in late summer and fall. Sempervivums, or hens and chicks, are also extremely drought tolerant and have colorful flowers.

Some plants have hairy or fuzzy leaves. The fine hairs keep moisture trapped at the leaf surface, which reduces the evaporation. California fuchsia, lavenders, rockroses and santolina survive this way. So do perennials like lamb’s ear, coneflowers, pincushion flower, wooly thyme, snow-in-summer and many Artemisias.

Plants with fine lacy foliage, designed to reduce leaf surface, lose less water through surface evaporation. These include Russian sage, yarrow, some verbenas and coreopsis.

A few plants, which are the lowest water users, drop their leaves and go dormant for the summer. The California buckeye drops its leaves in July or August and the flowering currant will go dormant in the summer if not irrigated.

It is important to remember that most plants, even drought-tolerant ones, need water initially in order to become established. Generally, they will need to be watered through one growing season. But if you plant in the fall, they will need less water the next summer than if they are newly planted in the spring.

There are water-conserving ground covers, shrubs, flowering plants and shade trees available for most any situation. With proper planning, you can enjoy a beautiful landscape without using a lot of water.

More Waterwise Landscaping

Saturday, May 16th, 2015 by Jenny Watts
    • Mother’s Day is the perfect time to give a gift of a living plant. Gardenias, hydrangeas, hanging fuchsias and ivy geraniums are sure to please her.
    • Gladiolus make wonderful cut flowers throughout the summer. Plant some every two weeks for continuous blooms.
    • Hang codling moth traps in apple trees to reduce the number of wormy apples in your harvest this year. Be sure to use a fresh pheromone (attractant).
    • Feed roses to encourage a beautiful display of color later this month. Treat plants to prevent insect and disease problems.
    • Plant an herb garden in a container near the kitchen door for convenient fresh spices like basil, oregano, parsley and thyme.

More Waterwise Landscaping

Water efficient landscaping includes grouping plants together with similar water requirements, watering just to meet the plant needs and using decks and patios to enhance your enjoyment of the yard.

Water zone 2 is made up of plants that can survive on watering twice a month. Of course, they need to get established before they can handle such infrequent watering.

Large shrubs that will grow here include the common lilac, Syringa vulgaris. Hybrids come in many different colors and shrubs generally grow to be about 12 feet tall. Their fragrant spring flowers are a delight. The spring-blooming Forsythia, with its bright yellow flowers, is a very durable shrub that announces “It’s Spring” each February when it blooms.

Medium-sized shrubs include Japanese Barberry, Berberis thunbergii ‘Atropurpurea,’ which is a thorny, purple-leaved shrub that grows 4-6 feet tall and makes an excellent hedge. Flowering Quince, Chaenomeles japonica, is well-known for its red flowers that are among the first to bloom in the spring. It is also thorny and a very dependable shrub.

Low-growing shrubs to use here are the attractive native groundcover, Arctostaphylos uva-ursi. This is a low-growing type of manzanita that spreads quickly and always looks good. Bearberry Cotoneaster, Cotoneaster dammeri and Cotoneaster horizontalis, are evergreen groundcovers that grow only 1 foot tall and spread 8-10 feet wide. They are good-looking year-round and have red berries in the fall and winter.

Another good groundcover is Snow in Summer, Cerastium tomentosum, a grey-leafed plant that grows about 6-8 inches tall. The showy white flowers that appear in spring and summer give it its name.

For more flowers, plant Blanket Flower, Gaillardia x grandiflora ‘Arizona Sun,’ which is a showy perennial with large, red and yellow daisy flowers that blooms much of the summer. Daylilies, Hemerocallis varieties, have attractive trumpet-flowers that come in many colors. They make a large clump and are always attractive.

Many varieties of Penstemon can live on occasional watering. There are showy varieties like purple Midnight and red Firebird, but the native Penstemon heterophyllus has lovely sky-blue flowers that light up the garden.

Germander, Teucrium chamaedrys, is an excellent perennial ground-cover. It grows about a foot tall and covers itself with rosy-pink flowers in early summer. Black Eyed Susan, Rudbeckia fulgida ‘Goldstrum,’ comes into full bloom in late summer with bright, golden-yellow daisy flowers. It is a tough perennial that spreads willingly.

Your waterwise garden need not be without color! Choose some of these attractive and hardy plants to brighten your landscape.

Waterwise Landscaping

Wednesday, April 29th, 2015 by Jenny Watts
    • May Day is the perfect time to celebrate spring and to brighten someone’s day with a basket of flowers.
    • It’s time to put out oriole feeders. You can also attract them with fresh orange halves.
    • Flower seeds can be sown directly in the garden now. Cosmos, marigolds and zinnias will give you beautiful flowers all summer.
    • Plant the vegetable garden this month, but remember that late frosts can still nip tender young plants.
    • Beautiful African Violets will decorate your indoor spaces with their masses of flowers in all shades of purple, blue and pink.

Waterwise Landscaping

Waterwise landscaping is an approach to landscaping that emphasizes water conservation. By using plants that are more drought tolerant your landscape will be able to survive through long dry periods with a minimum of water. Using native and Mediterranean plants, a well-designed landscape provides diversity and beauty with minimum maintenance.

Water efficient landscaping includes grouping plants together with similar water requirements, watering just to meet the plant needs and using decks and patios to enhance your enjoyment of the yard.

To create a landscape that uses minimal irrigation, the secret is to use tough, drought-tolerant plants that will grow in the amount of sun or shade available in a particular site. You can use plants that like more moisture along north and east facing slopes and walls. Don’t mix plants with high and low water needs in the same planting area.

Shrubs that will grow well in these conditions include rockroses, California wild lilac, lavenders, rosemary, manzanitas, mugo pines and junipers. In addition, common shrubs like forsythia, barberry, Oregon grape, cotoneaster, Philadelphus and lilacs can get by with occasional summer watering. These will give you a variety of sizes and textures to fill large spaces and tumble over rocks and down hillsides.

Add color to the setting with some of the many perennials that tolerate these conditions. The following plants are very drought tolerant. They should survive with a monthly irrigation once established, but you may choose to irrigate them twice per month from June through August for additional flowering.

Reliable, easy-care yarrows have flat clusters of colorful flowers and finely divided, fern-like foliage. Smaller varieties, like ‘Pomegranate,’ are low growing with 18-inch flower stems while ‘Moonshine’ grows to two feet and ‘Coronation Gold’ can reach four feet tall. They bloom through early summer.

Coneflower, Echinacea purpurea, has large, showy daisy flowers that bloom from early to late summer. Some exciting new varieties have flowers in bright reds and yellows with names like ‘Hot Coral’ and ‘Cheyenne Spirit.’

Red Valerian is a well-known plant in many older gardens, where its rosy-red flowers on tall, floppy stems bloom continuously from late spring through summer. It reseeds readily and is easy-to-grow.

Sedums are often overlooked but these succulents are excellent in sunny spots with well-drained soil. From the low-growing ‘Cape Blanco’ with its attractive silver-gray foliage, to the 24-inch tall ‘Autumn Joy’ with its large domes of bright pink flowers, sedums contrast beautifully with more delicate plants.

Very large areas can be planted with a wildflower mix. Now is a good time to broadcast these seeds. The mix may include California poppy, lupine, purple coneflower, and gaillardia.

There are many more plants that will survive with watering just twice a month, which I will share next week. By designing your landscape with drought tolerant plants, you can make the most of our precious water resources.