California Native Plants, drought tolerant groundcovers, drought tolerant plants, heat resistant plants

Plants that Hold up in the Heat

What happens to a plant when the thermometer tops 100 degrees like it did a couple weeks ago? Planning for more hot weather this summer is a requirement for a successful garden. Are there some plants that can survive tough times more easily?

Bees Bliss salvia

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 hight heat can be stunted, weakened and attract pests and diseases even if water is available.

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 do take resources away from a plants other needs like growth, flowering and fruiting.

It?s no surprise that many California natives are adapted to high temperatures. In my own garden I grow several plants that are doing quite well without irrigation and handled the heat wave just fine. One is Bees Bliss Sage, a low groundcover that can reach 6-8 ft wide draping over rocks and walls. 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.

salvia clevelandii

Another plant that can handle high temps is salvia clevelandii. Right now it has just started its blooming cycle of electric blue-purple flowers. They will last through the summer. This salvia survives without any supplemental irrigation but if I give it an occasional deep watering and wash off the foliage every so often its much happier.

mimulus arantiacus

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.

As summer comes along the California fuchsia will provide the color in the garden. I like it that they spread by underground rhizomes and self sow. Free plants are always welcome. I have them planted on a slight slope where they tumble over a rock wall. My bees and hummingbirds find this plant irresistible.

penstemon heterophyllus

Other California native plants that can handle the heat with little water include 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.

These plants can be the rock stars of your garden. Some natives can survive with no water after 2 years many look more attractive with a few deep waterings per summer. And don?t forget the organic soil amendments and wood chip mulch to encourage the soil microbes and keep the soil cool.

bouquets, cut flowers, Filoli Garden, mixed bouquet

Cut Flower Tips

Don?t have much space to devote to a cutting garden? No problem. Although we all dream of a dedicated spot in the garden set aside for growing masses of flowers and foliage for bouquets, it?s not a necessity. Many great plants for cutting can just as easily be grown in raised beds, containers and between shrubs. So whether your prefer formal floral bouquets or casual, deconstructed flower and foliage arrangements let your imagination run wild and grow plants that make either easy to put together.

Mixed bouquet at Filoli Gardens

While just about any plant material that strikes your fancy will work in a mixed bouquet there are four types of plant forms that naturally look good together. First are the spires for height and architectural properties. Flowers like liatris, snapdragon, gladiola, salvia, Bells-of-Ireland as well as the strappy leaves of New Zealand flax or cordyline fall into this category. Secondly are plants and foliage with a round form for focus such as roses, dahlias, long-stemmed marigolds and peonies. Last are the lacy accents for fillers- ferns, baby’s breath, dill and foliage from shrubs such as abelia, breath of heaven, smoke bush, Japanese maple and ornamental grasses. Grapes and other vines and herbs are also good as accents.

A deconstructed arrangement separates each type of flower into their own vase or container instead of grouping them in a mixed bouquet. Vary the size and shape of the vases and containers and group them together to create a unique vignette.

In shady gardens, fragrant daphne odora is a wonderful small shrub that provides interesting variegated foliage as well as flowers. Sweet olive or osmanthus fragrans blooms smell like apricots. Oakleaf hydrangea foliage and flowers look great in bouquets and the leaves turn red in fall which is an added bonus. Our native shrub philadelphus, also called mock orange, has flowers that smell like oranges and will grow in some shade as well as sun. Pittosporum ?Marjorie Channon? will add white with a hint of lime to your bouquets.

Kangaroo paw (Anigozanthos)

For sunny spots grow penstemon and kangaroo paw. Coreopsis attract butterflies and are long lasting in bouquets.
Perennial coneflowers, dahlias, gloriosa daisy, delphinium, foxglove, scabiosa, aster, shasta daisy and yarrow are good as cut flowers. Self-sowing annuals that have a long vase life are bachelor buttons, clarkia, cosmos, flax, love-in-a-mist, nasturtium, cleome and calendula.

Native flowers that last for a week or more include Clarkia and Sticky Monkeyflower. Yarrow and hummingbird sage will last 4-6 days.

Mixed spring bouquet

To make cut flowers last, pick them early in the morning before heat stresses them. Flowers cut in the middle of the day will have difficulty absorbing enough water. Cut non-woody stems on a slant for maximum water absorption. Woody stems can be cut straight across but smash the ends. Plunge immediately in a bucket of tepid water. Indoors, fill a container with cool water and recut each stem under water so an air bubble doesn’t keep the water from being absorbed.

Pull off any foliage or flowers that will be below the water level in the vase. Fill a clean vase with 3 parts lukewarm water mixed with 1 part lemon-lime soda, 1 teaspoon vinegar and a crushed aspirin. Another recipe for floral food is 2 teaspoons sugar, 2 tablespoons white vinegar and 1/2 teaspoon bleach in 1 quart water. The sugar helps buds open and last longer, the acid improves water flow in the stems and the bleach reduces the growth of bacteria and fungus. Change the water and recut the stems every few days to enjoy you bouquets for a week or maybe even two.

 

hedges, screening plants

When You Need to Screen

The first ?landscape emergency? call came from a homeowner in the Felton Grove neighborhood. She lost 100 feet of fencing this winter during four separate floods. ? I need plants to screen the new wire fencing from the road and I need it fast,? she said.

The next call came from Boulder Creek. A row of pesky acacias had recently been cut down exposing the house to road traffic. This homeowner wanted plants that would fill in quickly, be low maintenance and have low water requirements. Every landscape situation calls for a different solution and there?s one for every garden.

Coleonema- Pink Breath of Heaven

When you plant new shrubs that you plan to turn into a hedge, know what to expect and then let each plant develop in its own way rather than trying to make it into something its not. Any plant can be pruned and trained into any shape but that creates more work than if you selected shrubs than naturally grow into a form that pleases you.

Good shrubs for screening that naturally stay between 6-15 feet include California natives such as ceanothus ?Concha? or ?Julia Phelps?, California coffeeberry and mahonia. Other good performers are westringia ?Wynabbie Gem?, New Zealand tea tree, oleander, pittosporum ?Marjorie Channon?, purple hopseed and escallonia.

Many times a screen may start in the sun but end up in mostly shade. For your sunnier spots why not mix in a few dwarf fruit trees to enjoy, ceanothus and Pacific wax myrtle for the birds, barberry for the beautiful foliage and fall color, spirea, rockrose, escallonia and quince for their bright flowers and fragrant lilacs for cutting in the spring?

Prostanthera o, ‘Variegata’

The shadier side can include Oregon grape for fragrant, yellow winter flowers, snowberry for those striking white berries in the fall, oak-leaf hydrangea, viburnum and native mock orange for blossoms in the spring. Loropetalum have beautiful flowers and burgundy foliage while variegated mint bush ( prostanthera o. ‘Variegata’) sport lovely purple flowers and fragrant foliage. Mixed hedges appeal to bees, butterflies and songbirds while also providing flowers, berries and color throughout the year for you to enjoy.

Bare spots in a hedge are caused by old age and repeated shearing without allowing the hedge to grow. The problem can be alleviated by cutting away dead twigs, branch by branch and then shearing outside the last cut next time you prune.

To keep down maintenance, mulch around your plants and install drip irrigation. There won’t be any pruning to do if you choose plants that grow to the height you want.

Purple hopseed

How close should you plant a mixed hedge? Depending on the mature size of the plant, spacing could be from 3-5 feet part If you want a quick, thick screen.This gives them room to breathe and develop their own shapes. Fast growing plants can be space 5-6 feet apart or more and will usually fill in within 5 years.

Provide the best growing environment for the fastest results. By this I mean amending the soil at planting time if your soil is not very fertile. Cover the soil with mulch and fertilize with compost or organic fertilizer. Water deeply when needed especially during the first three years when young plants put on a lot of growth. Formal hedges are fine for some gardens but think of all the added benefits you’ll get planting a mixed hedge.

 

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