Tag Archives: drought tolerant plants

Design trends

Knee High by the Fourth of July

Also known as Siskiyou Lewisia is an easy to grow perennial that thrives in sandy soils.

I don’t grow corn in my small, shady garden so I’m not sure how tall they’d be if by now if I planted on May Day when the soil was 50 degrees, but that’s how the saying goes. And from what I’ve read about the early hot weather in the midwest, their corn is higher than knee high. But this column isn’t about growing corn, it’s about climate smart plants that hold up to the heat. So let’s get started.

All this talk about “drought tolerant” plants or “water smart” plants is misleading in some ways. What really matters for the success of a plant in your garden is that they are climate smart. You can call the new California garden climate tolerant or climate adapted but it all comes down to the same thing. The plants you choose to grow in your garden should be able to naturally tolerate periods of lower than average water. This doesn’t mean no water during extremely long dry periods. No plant can live without water.

I have two books that I look to for plant ideas when called upon to design a garden in our area. This first was published by East Bay MUD in 2004 and is called ‘Plants and Landscapes for Summer-Dry Climates’. The other book I refer to regularly for ideas and information is ‘California Native Plants for the Garden’. Both are invaluable in these times of water conservation. One of the best tips each of them offer is to garden where you live.

Silver-leaf manzanita

All of us live in a summer-dry climate. Summer-dry gardens are naturally dry for long periods. Knowing which type of plant community you live in can make the difference between success and failure in your garden. Choose the right plant for the right place whether it’s a California native from an area with similar soil and exposure or a plant from another Mediterranean-like climate with growing conditions like yours.

Plant communities have evolved over time with geologic changes in climate, topography and soils. We have several district areas here- mixed evergreen forest, redwood forest, chaparral and sandhills.

If you live in a mixed evergreen forest you garden with trees like coast live oak, tan oak, madrone, bay and buckeye. Understory plants include ceanothus, coffeeberry, hazel and poison oak. Your soil contains serpentine and granite. Many other unthirsty plants like salvias, lavender, santolina, society garlic, giant feather grass, rosemary and rockrose do well here. California natives such as western mock orange (philadelphus lewisii), wild ginger and western sword ferns grow here also.

Mixed evergreen forest may also be found along canyon bottoms near streams where big leaf maple, white alder, cottonwood, and western sycamore trees grow. Most plant here grow lush in this deep soil. If you are looking to add something new to your garden here consider giant chain fern, aquilegia, dicentra, Pacific Coast iris and fuchsia-flowering gooseberry.

This mimulus auritanicus is growing in the hottest, driest conditions and thriving.

Chaparral areas are the hottest, driest slopes of these mountains. Dense thickets of manzanita, coyote brush, chamise, coffeeberry, ceanothus, monkey flower and sage are native here. These plants are adapted to little water and often have tiny, thick, waxy, light green or grayish leaves. Soils tend to be rocky and shallow with overlaying rock or a subsoil that is mostly clay. Plants here need to have an extensive root system that reaches widely and deeply for water. If you live here a classic combination would be the spring blooming western redbud and Julia Phelps or Dark Star ceanothus. The combination of magenta and electric blue flowers is unforgettable.

The sandhills near Quail Hollow and Bonny Doon around Martin Rd. are part of an ancient sandy sea floor that was uplifted, eroded and exposed. These sandy soils lack organic matter and nutrients and their white color magnifies the temperature of the summer sun. Unique, native plants like silverleaf manzanita and Ben Lomond wallflower live here. Buckwheat and sticky monkey flower do well here. You might also try growing Siskiyou Lewisia, a pretty little plant native to northern California, thrives in sand and gravel soils with good drainage. This 8″ tall hardy perennial blooms from spring to early summer with extremely showy flower clusters in colors ranging from apricot to pink, rose and bright cherry red. Mulch them with gravel or crushed stone.

Remember right plant-right place. Don’t try to force nature although most gardens do look better with some summer water. Closer to the house we expect a fuller look. Combinations I’m going to try this season include leucospermum paired with blue echium or grey-leafed westringia planted with red-flowering callistemon ‘Little John’.

Design trends

Helping your Garden Survive the Heat

Matilija poppies are known as Fried Egg plant. Be careful the sap of this plant
is poisonous to humans and animals.

Looks like we’re in for a hot summer. Already we’ve had scorching temperatures and since it’s only the beginning of July, you can bet there will be more hot spells. How can you help your plants survive a heat wave? Are there some plants better adapted to handle hot temperatures?

Photosynthesis is one of the most remarkable biochemical processes on earth and allows plants to use sunlight to make food from water and carbon dioxide. But at temperatures about 104 degrees the enzymes that carry out photosynthesis lose their shape and functionality. A garden that provides optimum light and water but gets too hot will be less vigorous. Tomatoes, for example, will drop blossoms and not set fruit if temperatures are over 90 degrees. Plants that endure high heat can be stunted, weakened and attract pests and diseases even if water is available.

Understanding how plants respond to heat stress is important for developing crops that can withstand rising temperatures and more frequent heat waves under climate change. Much research is being done to counter drastically reduced crop harvests from increased temperatures.

California Fuchsia has adapted to heat and drought.

Plants do have natural systems that respond to heat problems. Some plants are better at this than others. Plants can cool themselves by pumping water out through the leaves for a kind of swamp cooler effect. They can also make “heat-shock” proteins which reduces problems from over heating. All these strategies take resources away from a plants other needs like growth, flowering and fruiting.

Plants respond to heat stress by activating hormones which act as chemical messengers. Brassinosteroids are one of these hormones. They have growth promoting properties as well as the ability to increase the heat stress resistance of plants. Because it is a natural product it is approved for organic farming. Research continues to create varieties that are more resistance to heat stress and also provide more stable harvests.

It’s no surprise that many California natives are adapted to high temperatures. Bees Bliss Sage, a low groundcover that can reach 6-8 ft wide is a plant that can It has an extended bloom time from mid-spring to early fall with whorls of lavender-blue flower spikes. Bees, butterflies and hummingbirds all find it attractive.

Another plant that can handle high temps is salvia clevelandii. Their blooming cycle of electric blue-purple flowers will last through the summer. This salvia survives without any supplemental irrigation but if you give it an occasional deep watering and wash off the foliage every so often it’s much happier. All the salvias are good performers in the heat. Just be sure to keep them groomed of dead leaves and branches to keep your garden fire safe.

Jelly Bean Gold Mimulus

Who doesn’t like color in their garden? Mimulus or Sticky Monkey Flower blooms are showy and the hummingbirds love them. The Jelly Bean series has added bright pink colors in addition to white, orange, red and yellow but the traditional aurantiacus types are the most tolerant of drought.

Other California native plants that can handle the heat with little water include matilija poppy, eriogonum, manzanita, artemisia, California milkweed, California fuchsia, ceanothus, mountain mahogany, bush poppy, bush lupine, native penstemon, monardella, mahonia nevinii , fremontodendron and holly-leafed cherry.

Non-native but well-adapted plants that are known to be more tolerant of heat include butterfly bush, germander, rosemary, smoke tree, rudbeckia, coreopsis, lantana, plumbago, gaillardia, lilac, sedums, oregano and verbena.

These plants can be the rock stars of your garden. Some natives that are able to survive with no irrigation after 2 years may look more attractive with a few deep waterings per summer. And don’t forget the wood chip mulch (not bark chips) to encourage the soil microbes and keep the soil cool.

Design trends

These are a Few of my Favorite Plants

While staying at a friend?s house during the evacuation I was able to stroll through her garden. She?s also a landscape designer and her garden is as beautiful as you?d imagine. She?s addicted to plants and keeps adding to her megs collection on a regular basis. Among the blooming perennials I came across were some of my person favorites. All three are wonderful low water, wildlife and pollinator friendly plants.

Epilobium ‘Everett’s Choice’

The first plant that caught my eye was an epilobium ?Everett?s Choice?. The name Epilobium is considered current but this group of sub-shrubs used to be called Zauschneria and are so different from the other epilobiums like Fireweed that many California native plant enthusiasts and even the experts often still refer to them as Zauschneria.

This low-growing vigorous ground-hugging shrub remains under 6 inches tall by up to 4 to 5 feet wide with fuzzy gray-green leaves that are covered with long whitish hairs. Vivid red-orange tubular flowers are produced in profusion in the late summer into fall. It does best in full sun but will tolerate some shade. Quite drought tolerant, but remains a fuller and more attractive plant with an occasional summer watering. It likes well-drained soil best but will do OK in heavier soils if not over watered. California fuchsia are deer resistant and attractive to hummingbirds.

Echo Mango kniphofia

The second plant that caught my eye is also a hummingbird magnet. Kniphofia, also called Red Hot Poker blooms spring into summer with torch-like clusters that open from the bottom up. The selection at my friend?s garden was probably Echo Mango. Whether the cultivar blooms with red, yellow, orange or mango colored flowers this perennial grows to about 3 feet tall and 4 feet wide in full sun. It is evergreen and requires little summer water. Deer don?t like this plant either so that?s a plus and it?s hardy to below 15 degrees.

Sdum ‘Autumn Joy’

Many of you already grow sedum spectabile ?Autumn Joy?. A succulent perennial to 1-2 feet tall it has wide cabbage-like rosettes of pale blue-green leaves and rich, dark pink flowers that put on a spectacular show above foliage in summer and fall. Plant in sun in a dry well-drained soil and water however much or little you want. The foliage dies back in the winter but is root hardy to below -30 degrees. This group of sedum was given the prestigious Royal Horticultural Society?s Award of Garden Merit in 1993. Beautiful in the rock garden, perennial garden or spotted into a natural meadow setting it attracts bees and butterflies and is deer resistant. The seed heads can be left for winter interest as well as a food source for birds but stems should be removed prior to the new buds opening in February.

Any one of these plants would be a lovely addition to your garden if you don?t already grow them.