Tag Archives: drought tolerant plants

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

Ceanothus: The Most Valuable Plant in your Garden

Those of you who read my column regularly might have noticed I often write about plants that are valuable to the birds and the bees as well as butterflies and wildlife in the general. I have 10 bird feeders around my house. Four for the hummingbirds and the other six have black oil sunflower seed and hulled chips. At this time of year when there are so many young the extra food is much appreciated. I provide water and nectar plants for the bees and butterflies as well. If I had to choose one plant to grow that would provide the most benefit for all the critters it would be ceanothus. Hands down, it’s the best and here are some of my favorite varieties.

Ceanothus ‘Carmel Creeper’
Ceanothus ‘Heart’s Desire’

The groundcover varieties I have in my landscape are Anchor Bay, Carmel Creeper, Heart’s Desire, Centennial and Diamond Heights. If deer frequent your landscape you should stick with Anchor Bay, Heart’s Desire and Centennial but the others are great in protected areas.

One of the upright types I grow is ceanothus thysiflorus. It’s one of the earliest native shrubs to bloom in our area. Ceanothus thyrsiflorus grow along a narrow band close to the coast from Monterey to southern Oregon. I also grow Julia Phelps with those electric blue flowers and Ray Hartman.

A new variety I’ve recently learned about from my friend and fellow Press Banner columnist, Colly Gruczelak, is called Celestial Blue. She planted several 2 years ago from 4″ mail order sleeves and they are now 3 ft tall and 4 ft wide. In her sandy garden, home to her personal deer population, the flowers look like blueberry sherbet. With a light fragrance, described as grape tart, it makes a good screen or accent. This cultivar is probably a hybrid of Julia Phelps and Concha. A horticultural cultivar is simply a plant variety that’s been selected specifically for gardens. Celestial Blue flowers 9 months a year especially in the summer when it explodes with rich purplish blue flowers.

A great variety I often use when designing a garden is Ceanothus ‘Concha’ because it will accept summer water more forgivingly than most and tolerates clay soil more than other species.

Joyce Coulter ceanothus also tolerates clay, summer irrigation and shearing better than other cultivars. It”s a good bloomer, drought tolerant and is covered in spring with wildly fragrant blue three-inch flower spikes.

Ceanothus is often said to be short lived. Most varieties need good drainage, little summer water and don’t need soil amendments. In their wild conditions ceanothus plants have a natural life cycle of 10-15 years although some live longer.

Diamond Heights ceanothus

Several members of the ceanothus family can form a symbiotic relationship with soil micro-organisms and fungi, forming root nodules which fix nitrogen. This is a reason why fertilizing is not normally recommended. Adding fertilizer mights kill off the good micro-organisms. Ceanothus are better left fending for themselves.

Ceanothus provide excellent habitat for birds and insects. They are good for attracting bee and fly pollinators and are the larval host plants for the beautiful ceanothus silkmoth. Ceanothus seed is readily eaten by many local birds. Planting a ceanothus is an important step to attracting more birds and wildlife to your garden.

Early California Indians used the fresh or dried flowers of some varieties for washing, lathered into a soap. it has been said to relieve poison oak, eczema and rash.

April in the Garden in the Santa Cruz Mountains

Spring might have officially started mid-March but judging from the wonky weather it’s hard to tell. We did experience a “Miracle March”  with a pretty good dose of needed rainfall along with some very cold weather. You never know what to expect in March around here.

Sherman, my Welsh springer spanial, enjoying a spring day in Scotts Valley

But now we’ve turned the corner on spring with flowers bursting open within hours on these nice days. The Black-headed grosbeaks have returned to my yard for the breeding season. Like clockwork they show up on almost the exact day each year. It’s my version of the swallows returning to San Juan Capistrano.

Looking forward to the rest of spring, here’s what I’ll be doing around here in April.

Hopefully we’ll have plenty of April showers. This latest rainfall is surely  welcomed. One of the perks of a cool, rainy spring is that shrubs and perennials have longer to establish a good root system before hot weather arrives, ground covers have time to spread and shade the soil, conserving moisture come summer. What strategies can you follow that will make your garden low maintenance this summer and give you extra time to enjoy it?

Plant in masses. When designing or reworking your garden, make it

ajuga reptans, a groundcover for shady spots

easy on yourself by planting fewer varieties but in greater numbers. Planting this way will reduce the number of different maintenance tasks for that area. For example, if you have a large hillside that you want to cover, plant it with a groundcover like ceanothus gloriosus which fans out 6-15 feet. Some manzanitas like arctotaphylos uva-ursi eventually spread to15 feet each. Sage leaf rockrose and germander are also good for sunny areas. A shady spot could be planted with ajuga, creeping mahonia or Walkabout Sunset lysimachia.

Another time saving strategy is to group plants with similar moisture needs. This may sound like a no brainer but if you have just one prima donna in a bed of more drought tolerant plants, you’ll be dragging the hose over to that bed for just one plant or having to run your irrigation system more for it. If you find that some of your plants are not quite as low water as you’d like, move those to their own spot. In general, plants with large leaves usually require more water and transpire faster while drought tolerant plants typically have one of more of the following characteristics: deep taproots and leaves that are smaller, silver, fuzzy or succulent.

ceanothus ‘Carmel Creeper’ – A low maintenance, low water groundcover for sunny spots

Avoid putting thirsty plants in hard-to-reach places. If the irrigation system doesn’t reach that far, keep it simple by planting drought tolerant woody shrubs or perennials there.

Pluck weeds when the soil is moist and before they have gone to seed. Even if you don’t get the entire root of more persistent weeds, just keep pulling at the new growth. Eventually, the plant will give up having used up all of the food stored in its roots. I’m still battling hedge parsley with it’s sticky seed balls that will cling to my shoelaces and the dog’s fur if I don’t get it before it sets seed.

Plant edibles among your other plants near the kitchen. Tricolor sage looks great alongside other plants with pink and violet leaves. Purple basil planted below the silver foliage of an artichoke is another great combination. Lemon thyme growing next to a burgundy colored dwarf New Zealand flax would look spectacular, too. And don’t forget to plant decorative and delicious Bright Lights swiss chard with its stalks of yellow, orange, pink, purple, red, green and white throughout your beds. It’s one of the easiest vegetables to grow.

So get the lemonade ready to enjoy all your free time later this season.

California Natives for Erosion Control

Who knows what the weather will be like this winter but what we do know is that some of our rain events will come with a vengeance. It’s not that unusual for our area to get 8 inches of rainfall during a storm and that can create havoc on an unprotected hillside. Fortunately, October is a good time to do something about it.

Pink Flowering Currant

Fall is the perfect time to plant in our area. The soil is still warm encouraging root growth and the weather is mild. Using the right plants on hillsides can help slow and spread runoff and prevent soil erosion. Mulch also protects soil from direct rain impact and slows runoff across bare soils. Covering the steepest slopes with jute netting through which plants may be installed is an added precaution.

There are many attractive plants that work well for erosion control. Often they need to adapt to shallow, poor soil and cope with less than ideal conditions all while putting down dense, strong roots. California natives are well suited to this job.

Common native shrubs include ceanothus and manzanita of all

Calycanthus occidentalis

types. Calycanthus or Spicebush has fragrant flowers in late spring blooming well into summer with a spicy fragrance. The foliage is aromatic when crushed and changes from a spring green color to pale golden in autumn. Decorative woody fruits last into winter making this shrub attractive year round. It thrives with infrequent to moderate watering. Combine with coffeeberry and deer grass in sunnier spots or with Douglas iris and giant chain fern in shaded spots below trees. All these plants have deep roots and control erosion.

Ribes s. King Edward VII

Ribes sanguinem or Flowering Currant is another show stopper capable of controlling erosion. In the spring the long, flower clusters of this deciduous shrub will dominate your garden. Choose from white flowering ‘White Icicle’ or ”Barrie Coate” and ‘King Edward VII’ with spectacular deep red flower clusters. ‘Spring Showers’ has 8 inch long pink clusters. Grow in full sun to partial shade. This California native requires little water once established and is a valuable nectar source for hummingbirds.

Some other good California native shrubs for erosion control are western redbud, mountain mahogany, western mock orange, lemonade berry, toyon, matilija poppy and western elderberry. ribes viburnifolium, creeping mahonia and baccharis. Ceanothus maritimus, ‘Heart’s Desire’ and ‘Anchor Bay’ are all good groundcover selections and are not attractive to deer.

Symphoricarpos – Common Snowberry or Creeping Snowberry – can hold the soil on steep banks. This native tolerates poor soil, lower light and general neglect.

Smaller natives that put down deep roots are yarrow, coast aster, California fuchsia, wild grape, mimulus, buckwheat, wild rose, sage and salvia.

Bush poppy -dendromecon rigid- is another native found right here in our area and needs no irrigation at all once established. Beautiful bright yellow, poppy-like flowers cover the plant in spring. They can be propagated from cuttings taken in summer and are pest and disease free.

Remember when setting plants on a steep slope to arrange them in staggered rows. Make an individual terrace for each plant and create a basin or low spot behind each one – not around the stem – to catch water. Set the crowns of the plants high so they won’t become saturated and rot after watering and make sure mulch does not build up around the stem.

 

Interesting Plants to Update your Garden

Tired of seeing the same plants in your garden and everywhere else? Feel like changing things up a bit? With this question in mind I’ve turned to my fellow landscape designers to see what plants they are using these days so that every garden they design doesn’t look the same. You can have too much of a good thing.

One thing I know for sure is that I don’t want to recommend a plant that hasn’t been shown to be a reliable grower in a variety of conditions. Sometimes the latest and greatest plant introduction turns out to be a dud. Other times a new cultivar of an old favorite hits a home run. Here are some oldies but goodies and new plants to add to your garden.

 

Loropetaum ‘Jazz Hands Dwarf PInk’

Loropetalum ‘Jazz Hands’ is getting the nod from everyone who’s grown it. If you love the deer tolerance, low maintenance. moderate watering and toughness of regular Chinese Fringe Flower this showy dwarf variety is even easier to grow. Staying low and tidy Jazz Hands Dwarf Pink has cool purple foliage with a cranberry undercurrent and hot pink blooms. It looks great combined with Jazz Hands Dwarf White. Local wholesale nurseries are growing it so it’s readily available.

Speaking of local sources for plants, we live in one of the prime growing areas for landscape plants. I recently learned that one of my favorite plants Canyon Snow Pacific coast iris is going through a difficult time. Seems it’s become less vigorous than the other colors in the Canyon series and the growers are working to improve their stock. We need to count on a plant’s performance. There’s enough other issues to deal with in our gardens without starting with a wimpy plant.

Cistus variegata ‘Mickie’

Rockrose have always been favorites in the low water use garden. There’s one with a low, mounding habit that hugs the ground and creates a super colorful accent to the sunny garden. With brilliant gold leaves splashed in the center with green this variegated cistus hybridus called ‘Mickie” is hardy in winter, grows only 14-18 inches tall and spreads to about 2 feet wide. Perfect for containers or smaller gardens.

If you like to include California native plants in your garden Woolly Blue Curls or trichostema lanatum has been shown to be reliable in the garden if given full sun, good drainage and little fertilizer or amendment. Group similar plants and forget about them. They bloom from late spring through summer and make a good cut flower. Another common name for this plant is Romero or California Rosemary which dates back to the Portola expedition in 1769.

If you want to make a big splash in your garden or container try growing Salvia ’Amistad’ or Friendship Sage. With fast growth in the warm months to 4 or 5 feet tall, the rich royal purple flowers attract hummingbirds and butterflies to the garden. It will grow in light shade with medium water requirements and remain evergreen in warmer parts of your garden.

Cousin Itt acacia

Acacia ‘Cousin Itt’ continues to be a favorite for many of us. This lovely small plant with emerald green, feathery foliage that stays small in the garden and has low water needs. Not to be confused with the bully acacia tree seen around here, it’s one of the good guys. Plant in full sun to partial shade.

So if you’re in the mood to add a couple of interesting plants to your garden, take a tip from what landscape designers use or grow in their own gardens.

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.