Tag Archives: drought tolerant plants

climate smart plants, Design trends, plant communities, plants for summer dry climates

Knee High by the Fourth of July

A black-tailed deer celebrating the Fourth of July.

Who doesn?t love corn on the cob fresh either from the garden or farmer?s market? But this column isn?t about growing corn or about patriotic deer, 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.

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.

Found in the sandhills, silverleaf manzanita is perfectly suited to its environment.

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 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?.

autumnal equinox, California Native Plants, drought tolerant groundcovers, hummingbird plants, UCSC Arboretum

Autumnal Equinox

The autumnal equinox will arrive on Monday, September 23rd this year. It’s the official start of fall when the sun crosses the celestial equator and moves southward. The earth’s axis of rotation is perpendicular to the line connecting the centers of the earth and the sun on this day. Many people believe that the earth experiences 12 hours each of day and night on the equinox. However, this is not exactly the case.

During the equinox, the length is nearly equal but not entirely because the day is slightly longer in places that are further away from the equator – like where we live. Also the sun takes longer to rise and set in these locations as it does not set straight down but in a horizontal direction.

With the changing of the season, take advantage of fall planting weather. It was a hot summer and I?m ready for fall. This is the perfect time for transplanting or adding new plants to your garden. Why? Cooler air is kinder to plant foliage while soil temperatures are still warm creating an excellent environment for new root growth. In the fall many plants and trees, even broadleaf evergreens, are entering a period of dormancy. With no need to allocate resources into foliage, plants are transferring all their energy into roots and storing nutrients for the cool months ahead. By spring, the new root systems should be well established.

I had hoped to spend some time at the UCSC Arboretum earlier this year when the showy pincushion and leucospermum protea were flowering but I never made it. Because anytime?s a good time to visit the arboretum I dropped by recently. There is always something in bloom there and the hummingbirds know it. Here are just a few of the spectacular fall blooming plants that you might want to add to your own garden.

Leaucadendron Jester

The Leaucadendron ?Jester? (Sunshine Conebush), another type of protea, were loaded with brilliant deep wine-red bracts. This evergreen shrub grows to 5 feet tall and is very pest and disease resistant. Deer aren?t interested in the showy bright pink, cream and green foliage and it?s quite drought tolerant once established. You can cut the branches as they are prized for use in floral arrangement. People think that protea are hard to grow but really it?s a plant-it-and almost-forget-it kind of plant. They need good drainage and don?t like phosphorus fertilizer preferring poor soils with minimal care. Sounds like a winner to me.

Epilobium ‘Mattole Select’

A little further down the trail I came across another easy to care for plant. California fuchsia have undergone several name changes over the years but whether you call them epilobium or zauchneria they are in bloom now. The ‘Mattole Select’ cultivar forms tidy 6 inch high mats of beautiful silver foliage. Late summer through fall brings orangey-red tubular flowers which attract hummingbirds. Spreading by underground rhizomes, this epilobium increases size a little less vigorously than the others. It?s more shade tolerant than most California fuchsias and needs just a bit more water but it?s still quite drought tolerant. Pruning plants down to a few inches in late autumn helps rejuvenate them for the following year.

Grevillea junipera ‘Monoglo’

As I followed the hummingbirds around the arboretum I came across another groundcover that both the birds and the bees favored. Grevillea juniperina ?Molonglo? (Juniper Leafed Grevillea) blooms with a soft yellow flower unlike most grevillea. This fast growing evergreen forms a mass of dark green soft needle-like leaves and bears an extremely profuse show of light golden yellow flowers from late spring to winter. This tough hardy drought tolerant plants is the perfect groundcover for large areas and will cascade down slopes and walls.

I?m looking forward to another visit to the arboretum this winter as the Australian garden will be in full bloom then.

California Native Plants, drought tolerant gardens, drought tolerant plants, gardening tips, watering

Watering Plants in the Summertime

All plants need water– even those that are tolerant of our summer dry conditions. Water makes up 90-98% of every plant we grow. It’s needed for photosynthesis, as well as reproduction and defense against pests.

What happens to a plant when the thermometer tops 100 degrees? Are there some plants that can survive tough times more easily?

Mimulus ‘Jelly Bean Gold’

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. At temperatures about 104 degrees, however, 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 do endure hight heat may be stunted and weakened attracting pests and diseases even if water is available.

Plants have natural systems that respond to heat problems. 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 can take resources away from a plants other needs like growth, flowering and fruiting.

California fuchsia

It?s no surprise that many California natives are adapted to high temperatures. Some California native plants that can handle the heat with little water include salvia, mimulus, California fuchsia, eriogonum, manzanita, artemisia, California milkweed, ceanothus, mountain mahogany, bush poppy, bush lupine, native penstemon, monardella, mahonia nevinii, fremontodendron and holly-leafed cherry.

Other 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.

So how much water do different types of plants need during the heat of summer?

Be sure that you water trees and shrubs deeply checking soil moisture first with a trowel. Established small to medium shrubs should be watered when the top 3-6″ is dry, large shrubs and trees when the top 6-12″ is dry.

As a rule of thumb, trees and large shrubs need deep but infrequent irrigation. They should be on a separate valve than your smaller shrubs and perennials. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots grow 12-36? deep and require 10 gallons of water per inch of trunk diameter.

Bush Poppy

Apply water with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water district?s restrictions. Don?t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a smooth rod that?s 1/4 inch – 3/8 inch in diameter into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

The roots of smaller shrubs are 12-24? deep in the soil. Established native shrubs may need only monthly waterings to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12? or so and may need watering once or twice a week depending on type.

With lots of mulch and the above watering tips you can keep all your plants happy and healthy