Category Archives: perennials

Tranquil Blue in the Garden

With the heat of summertime upon us I’m drawn to those areas in my garden that have blue, white and lavender flowers. A hot day just seems cooler there.

Washed out magenta is nature’s favorite go-to color and the shade that hybrids will revert to it if allowed to go to seed. Among gardeners, red is a favorite color. Orange and yellow come next, then pink and purple with blue and white both comparatively rare in nature last on the list.

geranium ‘Orion’

So naturally, most of us gardeners want the elusive blue flower in our gardens. Knowing that cool colors recede, place them around the edges or at the back of a garden to make your space appear wider or deeper.

True blue flowers are rare. We use words like cerulean, azure, cobalt, sapphire, turquoise, electric blue or steel blue when describing blue flowers. Hybridizers have tried for years to produce a true blue rose or blue daylily. Blue plant pigment is hard to manipulate. It occurs in the daylily as a sap-soluble pigment and is difficult to segregate. Lilacs, purples, orchids and mauves we have and working with them hybridizers may eventually get near blue, but pure blue probably never. Recently, some companies have found a way to insert some blue in the center of their daylily flowers but a totally blue daylily has never been produced.

Rose hybridizers striving for true blue have come close by

hydrangea macrophylla

crossbreeding lavender hybrid teas in order to produce offspring having optimum amount of cyanidin, the pigment that imparts purple or magenta tones and flavone, the pigment that gives light yellow tones.The results have been more of a silvery lilac or mauve. A blue rose is still in the future although labs in Australia and Japan are genetically modifying the pigments from petunias to produce a blue rose. Their results are not yet perfected and these roses are more of a lilac in color and can not survive conditions outside the lab. It is apparently very difficult to isolate the pigment cyanadin. Delphiniums have a monopoly on it.

omphaloides

The color blue is calming and tranquil. It is the color of serenity and peace and is said to slow down the metabolism and reduce the appetite. When brightened with white or combined with yellow or orange in a complementary color scheme the results of blue in the garden are breathtaking. The great English gardener Gertrude Jekyll used plants with golden leaves or clear yellow flowers to spice up blue gardens. Just remember that blues and purples are the first flowers to fade as darkness falls so be sure to have those whites and yellows to carry your garden into evening.

There are many blue perennials as handsome as they are durable that we can enjoy in our gardens today.
Some of my favorites are old fashioned hydrangeas, violas and campanula. Both are valuable in the shade garden along with omphaloides and brunnera. The blue spikes of a long blooming peach-leaf campanula just go together with the white and green variegated foliage of Jack Frost Siberian bugloss.

agapanthus africanus

In early spring we are dazzled by our native ceanothus which bloom with deep blue, sky blue or electric blue flowers. Emerald Blue phlox subulata carpets the ground in spring with clear blue flowers that top creeping stems. Penstemon Blue Springs, a California native hybrid, carries dense spikes of bright blue, bell-shaped blossoms.

Make sure your garden has a blue section to cool you on a hot day.

Why Prune in the Summertime?

Pruning is a good way to spend a couple of hours in your garden. I’m not talking about trimming plants into little balls but the kind of pruning that makes for a healthier and happier plant.

Sango kaku Japanese maple- summertime

If you grow Japanese maples now is the time to remove dead branches and train your tree to look like one of those specimens you see in the magazines. Thinning cuts build your ideal tree limb structure. If yours is a young tree, though, don’t be tempted to head back long branches too soon. As these mature they give your tree that desirable horizontal branching.

This principle is important to keep in mind when you train any young ornamental tree. Lateral buds grow along the sides of a shoot and give rise to sideways growth that makes a plant bushy.

Summer pruning of fruit trees controls size by removing energy-wasting water sprouts. Summer is also a good time to remove leafy upper branches that excessively shade fruit on the lower branches. Winter pruning is meant to stimulate the tree. Summer pruning uses thinning cuts-where the branch is cut off at its point of attachment instead of part way along the branch- and these cuts do not encourage new growth but control the size of your tree making fruit harvest easier.

Summer pruning also can control pests like coddling moths, mites or aphids. Just be sure to dispose of these trimmings and don’t compost them.

Espalier apple tree

If you have apricots and cherries, summer pruning only is now advised as they are susceptible to a branch killing disease if pruned during rainy weather. Prune stone fruits like peaches and nectarines after harvest by 50%. They grow quite rapidly. Apricots and plums need to have only 20% of their new growth pruned away.

Be sure to thin the fruit on your trees. That’s another good reason to keep them smaller so you can more easily reach the branches. The best time to do this is when the fruit is still small. Thinning fruit discourages early fruit drop and improves the quality of the remaining fruit. It helps to avoid limb damage from a heavy fruit load. Also it stimulates next year’s crop and helps to avoid biennial bearing. Left to their own devices, a fruit tree may bear heavily one year and then light or not at all the next year. Some types of fruit trees like peaches and Golden Delicious apples are likely to bear biennially if the current year’s fruit crop isn’t thinned.

While I have the pruners out I’ll be shearing back early flowering perennials to encourage another round of blooms. And I’ll add some more mulch to areas that are a little thin. I’ll be checking the ties on my trees to make sure they aren’t too tight and remove the stake if the trunk is strong enough to support the tree on its own.

Also I’ll be looking for any pest problems so I can do something about them before they get out of hand. I’m OK with a few holes here and there but a heavy infestation should be trimmed off or sprayed with an organic insecticide. I also inspect the tips of my fuchsias regularly for fuchsia mites and clip off any distorted growth. I hate to spray even organics on them due to the hummingbird activity.

Most importantly, enjoy your time outdoors. If a task is too big to do at one time, break it down into smaller sessions. As they say, take time to smell the roses.

 

About Roses

Roses are the flower of love. Many of us have fond memories of favorites in our mother’s garden or of a beautiful bouquet given or received on Valentine’s Day. It’s dormant season for roses which is good for both pruning and adding a few to the garden.

David Austin rose

As a designer I have clients who have inherited roses and want to keep them as a remembrance. Others want to create a cutting garden filled with roses and other perennials. Don’t feel guilty for growing those beauties in your own garden. They use less resources than you think and there are many ways to grow them sustainably.

Roses, whether bush types, climber or ground cover carpet varieties, use a moderate amount of water in order to thrive according to the latest Water Use Classification of Landscape Species (WUCOLS) list. This amount of summer irrigation is the same as many of the plants on the list of Scotts Valley Water District’s 800 Approved Low Water-Use Plants for lawn replacement. Plants such as Emerald Carpet manzanita, Joyce Coulter ceanothus, Siskiyou Blue fescue grass, Pacific wax myrtle, butterfly bush, yarrow hybrids and Tapien verbena have similar water requirements.

Since now is the time to prune your roses here are a few tips.

Strike it Rich hybrid tea rose

Prune shrubs moderately to keep them compact. The goal is to keep the center of the plant open for good air circulation aiming for a vase-shaped bush with an open center. Cut out canes that cross, appear weak or are diseased, spindly or dead. Healthy canes appear green or reddish while old and dying canes are brown. Cut back the remaining stems by about one third. When pruning, cut canes at a 45-degree angle just above an outward facing leaf bud or a swelling on the cane. Clean pruners after every use to prevent the spread of disease and keep your pruners sharp.

Prune heirlooms roses such as David Austin and other old antique garden roses less because their open look is part of their charm.

Same goes for climbing roses. Cut out extra stems if there are too many and also cut back long established canes to about the place where they are slightly thicker than a pencil. Then cut each side stem down to several inches. This will make the cane flower along its complete length for a beautiful spring display.

Zepherine Drouhin climbing rose

Pluck off and rake away any old leaves. They can spread fungal spores. Consider spraying dormant plants with a combination of organic horticultural oil and copper soap or lime-sulfur. If you usually only have problems with black spot you can use a mixture of 1 teaspoon baking soda with a few drops of light horticultural oil in 1 quart water and spray every 7 to 10 days during the spring.

Prune your roses throughout the growing season, too. Deadheading, or cutting off spent flowers, encourages plants to re-bloom. Mulch around your roses to conserve water and encourage soil microorganisms.

Don’t worry whether you’re pruning job is perfect. Roses are super forgiving and you can always trim them up again later.

Late Summer Tasks for the Garden

It’s darker in the mornings now with the sunset coming earlier each evening. All that time I thought I’d have back in June to get things accomplished in the garden has vanished in what seems like a wink of an eye. Still the weather these days is perfect for being outside and pecking away at my to do list. There are also some late summer/early fall tasks that need attention.

alstroemeria_variegated
Alstroemeria ‘Rock & Roll’

Now through October, divide summer blooming perennials like alstroemeria, agapanthus, coreopsis, iris, daylily, yarrow, rudbeckia, calla lily, aster and penstemon that are overgrown and not flowering well. You can also divide spring blooming perennials like candytuft, columbine, astilbe, bergenia and bleeding heart although they don’t always bloom the first spring afterwards due to the energy they use re-establishing themselves. Start perennial flowers seeds now so that they will be mature enough to bloom next year.

This is the perfect time for transplanting or adding new plants to your garden. Why? Cooler air is kinder to plant foliage and soil temperatures are still warm which creates 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 roots system should be well established.

Perhaps it’s time to remove or reduce lawn. Replant with more drought tolerant ornamental grasses or perennials.

achillea_pink
Achillea millefolium

Fertilize shrubs lightly one last time with an all-purpose organic fertilizer or layer of compost. This advice doesn’t apply to California natives. They like compost only around the roots during the winter while they get ready for their growing season.

Roses especially appreciate a bit of fertilizer now, encouraging them to bloom another round in the fall. To keep them blooming make a habit of pinching and pruning off old flowers. Always cut back to an outward facing branchlet with five leaves. There are hormones there that will cause a new flower bud to grow much sooner than if you cut to one with only three leaves.

Plant cool season veggie starts like broccoli, cabbage, cauliflower, chard, lettuce, spinach, brussels sprouts, onions and leeks in soil enriched with 4-6″ of compost as summer vegetable crops will have used up much of your soil’s nutrients.You can sow seeds of beets, carrots, radishes, spinach, arugula, mustard and peas directly in the ground.

soil_builder_cover_crop_mix-1600
Soil builder cover crop mix

If you aren’t going to grow vegetables in the garden this fall consider planting a cover crop like crimson clover, fava or bell beans after you’ve harvested your summer vegetables.

Cut back berries vines that have produced fruit. Canes of the current season should be trained in their place.

Spider mites are especially prolific during hot, dry weather. Sometimes you don’t even know how bad the infestation is until all your leaves are pale with stippling. Periodically rinse dust and dirt off leaves with water. Spray the undersides of infected leaves with organics like insecticidal soap switching to neem oil if they build up a resistance to one of the pesticides.

And whatever you do, enjoy being outside in this beautiful place we call home.

What Landscape Designers Grow in their own Gardens

alstroemeria_Inca-Ice.1600It probably won’t come as a big surprise to you that I have a lot of friends that are also landscape designers. We get together to talk plants, garden design challenges and plant problems while enjoying good food along with a little wine thrown in for good measure. Recently I had the opportunity to visit one of these friends and although I was only there briefly to pick up something I couldn’t help but ask about several of the beautiful plantain her own garden. Some of her favorites include those with interesting foliage and texture and that flower over a long season. Maybe some of these plant ideas will work in your own garden.

Being winter and all I was immediately drawn to the hundreds of soft apricot and creamy yellow flowers covering a 3 foot wide Peruvian Lily. This selection of alstroemeria, called Inca Ice, is much shorter and compact that the taller ones that can be somewhat floppy in the garden. Alstroemeria were named by Carl Linnaeus, often called the Father of Taxonomy, for his friend and student Klaus von Alstroemer. Native to South America, the summer growing types come from eastern Brazil while the winter growing plants are from central Chile.

Peruvian Lily spread slowly outward from rhizomes and grow in full to part sun. They are hardy to 15-20 degrees and can tolerate dry conditions although they look best with irrigation. The Inca series grows 2-3 ft tall and can be covered with flowers from spring to late fall or winter if the weather is mild. The flower stems are long enough for cutting. This variety also comes in light orchid, pale yellow and white with red and green markings. What’s not to love about this plant?

Tucked next to the blooming Inca Ice Peruvian Lily, a clump of bright, Festival_grass-leucodendron.1600burgundy red Festival grass complemented the soft yellow of a Leucodendron discolor and a variegated Flamingo Glow Beschorneria. I was not familiar with this variegated agave relative with its soft-tipped chartreuse striped leaves. I found out this beautiful plant is drought tolerant, hardy to 15 degrees and will bloom with 5 foot pink stalks with reddish pink bracts.

Other plants that boast more foliage color than flowers brought this winter garden to life. Several varieties of helleborus just starting to show pink, white and rose color were surrounded by the brilliant chartreuse-yellow foliage of sedum Angelina ground cover. A variegated Japanese Lily-of-the-Valley shrub grew nearby getting ready to bloom soon.

Beautiful bright pink, cream and green variegated Jester Leucodendron bordered the driveway. I’ve seen this plant also called Safari Sunshine in nurseries. With its smaller size of 4-5 feet this evergreen shrub has showy, rich red bracts that sit atop the branches now in late winter and lasting into spring. Drought tolerant like Safari Sunset and deer resistant, too, leaucodendron are hardier than other protea.

Every interesting garden has good bones. It has focal points, texture, repetition and unity among other elements. My friends garden is no exception. A lovely caramel colored New Zealand Wind Grass dominated another area allowing my eye to rest for a while. I wish they would quit renaming this plant that used to be stipa arundinacea but is now anemanthele lessoniana. The name doesn’t exactly roll off the tongue but the effect is beautiful in the garden. I’ve always called it Pheasant Tail grass but I could find no reference as to why this common name is used. Life used to be simple before DNA sequencing!

So if you’re in the mood to add a couple of interesting plants to your garden, take a tip from what a landscape designer grows in her own garden.

Treats & Tips for the September Garden

salvia_m_Hot-LipsYou can feel the weather changing as summer winds down. It’s more than just the passing of the Labor Day holiday and the school year starting. The nights are longer and cooler. The days are not quite so hot and the flowers in the garden seem brighter and more colorful. I look past the soft blue and lavender blossoms and am drawn to the warm shades of gold, rust, orange, hot pink and red. They shout autumn is on the way.

There’s nothing quite like adding a few new perennials to brighten up the garden. There are many that don’t require a lot of water after they become established. I recently visited a garden where the irrigation was reduced to the point that that most of the plants were barely hanging on. But there among the crispy plants were two Hot Lips salvia blooming as big as you please. This plant is popular for a reason. Hummingbirds, butterflies and bees love it and it blooms for a long time. It stays compact and is a great carefree shrub for water wise gardens.

Daisy flowers always bring a smile to my face. As members of the composite family they have echinacea_Wild_Berrya flat landing surface for butterflies to land on. Coneflowers are one of my favorites. When they start blooming in the early summer I enjoy them both in the garden and as cut flowers inside. Some have a slight fragrance. Hybridizers have introduced beautiful shades of gold, yellow, orange, burgundy and coral in addition to the traditional purple and pure white. Because they are dormant in the winter they are good candidates for the garden that has summer sun but winter shade. They are not attractive to deer and are good additions to the low water garden.

gaillardiaAnother perennial that blooms throughout summer and fall is gaillardia also known as blanket flower. I’ve seen this tough plant grow in neglected gardens that the owner swears does nothing to keep it going. They are covered with dozens of large reddish-orange flowers with yellow edging and bloom over a long period. This plant also attracts butterflies. You can start perennials from seed at this time of year for next year’s bloom.

Don’t overlook the color of other foliage plants like Orange Libertia, Abelia ‘Kaleidescope’, New Zealand flax, red fountain grass and Japanese bloodgrass in the garden.

Now through October, divide summer blooming perennials like agapanthus, coreopsis, daylily and penstemon that are overgrown and not flowering well. You can also divide spring blooming perennials like candytuft, columbine, astilbe, bergenia and bleeding heart but sometimes they don’t bloom the first spring afterwards due to the energy they use re-establishing themselves.

Another thing to do while out in the garden this month is to cut back berries vines that have produced fruit. Canes of the current season should be trained in their place.

Spider mites are especially prolific during hot, dry weather. Sometimes you don’t even know how bad the infestation is until all your leaves are pale with stippling. Periodically rinse dust and dirt off leaves with water. Spray the undersides of infected leaves with organics like insecticidal soap switching to neem oil if they build up a resistance to one of the pesticides.

Soon it will be time to start cool season veggies or plant cover crops in the garden. It’s never too soon to start planning for erosion control in those areas that caused you problems during last spring’s storms. But for now add some early fall color and have fun in the garden.