Autumnal Equinox in the Garden

The autumnal equinox happens on Saturday, September 22nd 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.

ceanothus ‘Heart’s Desire’

With the changing of the season, take advantage of fall planting weather by looking at what’s covering your ground. Be it the small lawn for the kids to play on, ground cover to keep the weeds at bay or erosion control to keep the hillside intact, this is an excellent time to plan for winter.

Let’s start with the lawn. If you still need a space for recreation, this is a good time to reseed those bare spots. Also to keep the lawn healthy by removing underlying thatch with a thatching rake. Then aerate the lawn by poking holes in the sod and fertilize with a complete lawn fertilizer like an organic all-purpose. Your lawn needs the phosphorus in the fall to encourage deep, strong roots for the winter.

If the kids are grown and no one is using that lawn, why not rip out the water guzzling grass and replace it with a walk-on groundcover? There are many to choose from like dymondia, lippia, potentilla, duchesnea strawberry or any of the kinds of thyme.

Living ground covers add beauty to the garden while holding the soil in place and preventing erosion. They contribute to soil health by encouraging microorganisms. A garden wouldn’t thrive as well without groundcovers.

One of my favorites is Elfin thyme. It doesn’t need mowing, edging or fertilizing or much irrigation. You can walk on it and it stays green all winter, shading into bronze tones when the weather cools. It even blooms in midsummer for several weeks. Note that bees are attracted to it as with all of the ground covers in the thyme family at this time.

kurapia

Another favorite that I have in my own garden is kurapia. It’s deep rooted, doesn’t require much water, is compact and low maintenance. It’s been bred to have sterile seeds. This is a good groundcover if pollination of nearby fruit trees is needed or you want to encourage bees to your garden for pollination. If bees are an issue kurapia can be mowed to cut off the blooms.

There are also Ca. native and prairie meadow grasses that you can walk on. They need little irrigation and even less mowing. Some can be planted from seed, others from plugs or sod. Good choices include Idaho, California and red fescue, carex pansa, June grass and Hall’s bentgrass.

grevillea lanigera ‘Mt Tamboritha’

If you don’t need to walk on your groundcover, low-growing native shrubs that are good groundcovers are baccharis, ceanothus maritimus, ‘Anchor Bay or ‘Heart’s Desire’, manzanita, creeping snowberry, creeping mahonia, salvia ‘Bee’s Bliss’ and ribes viburnifolium. Mediterranean ground covers like cistus salviifolius, grevillea lanigera, rosemany prostratus, rubus pentalabous are also good low-water choices.

It’s time to enjoy fall weather and cover that ground before winter.

All About Mums

Can it be? Already I’m seeing my dogwood and crape myrtle showing signs of fall color. Pictures on Instagram and Facebook from other gardeners show early color on sumac and lilac. I know fall is in the air when the pink amaryllis belladonna bloom and I’m ready.

Garden mums

Mums are in their prime as early as September. We tend to think of chrysanthemums at Thanksgiving as temporary filler plants for fall containers and borders but mums are perennials and can play a bigger role in your garden if you let them. Established mums can tolerate quite a bit of neglect and still keep blooming every year.

Chrysanthemums were first cultivated in China as far back as the 15th century. Over 500 cultivars had been recored by the year 1630. In Japan records go back all the way back to the 8th century relating to mums.

The botanical name for the garden chrysanthemum has been changed to dendranthemum grandiflorum but I never hear anyone use this name. It doesn’t exactly roll off the tongue.

Yellow or white chrysanthemum flowers of the species. C. morifolium are boiled to make tea in some parts of Asia. In Korea, a rice wine is flavored with chrysanthemum flowers. Chrysanthemum leaves are steamed or boiled and used as greens in Chinese cuisine.

Another variety of chrysanthemum- cinerariaefolium- is important as a natural source of insecticide. The pyrethrins extracted attack the nervous system of all insects. Harmful to fish it should be used with caution but it’s not persistent in the environment and is biodegradable.

Grown for years to flower only in late summer and fall, they are short day plants, setting buds when they receive light for 10 hours and darkness for the other 14 hours of the day. This is why mums bloom in the spring on leggy stems if they are not cut back. And this is how growers manipulate their blooming, adjusting the dark and light periods with shades in the greenhouse so buds will form in any month. They’re nearly constantly available in grocery stores and florists in every season.

At this time of year when garden mums abound pick a plant with lots of buds. They bloom only once and won’t set more flowers until next year. Those buds, though, last a long time if you don’t let them dry out. Although mums are somewhat drought tolerant once established you should water deeply once or twice a week depending on the weather.

The specific type of plant doesn’t matter since they all have long term growth potential. If you particularly like one color or form of chrysanthemum, plant it now to enjoy again next year. You never know what the growers might decide to grow next season.

Choose a well-drained, sunny spot to plant them. Like many members of the aster family, mums won’t tolerate soggy ground. After blooming, trim off the old flowers and cut back plants to within a 4 or 5 inches of the ground. If you started with 4 inch pots, trim back by half.

Next spring pinch them back when they are 8 inches tall. Keep pinching until July, then allow plants to start forming buds for the traditional fall show.

A word of caution: all parts of chrysanthemum plants are potentially toxic to dogs, cats, humans and other mammals and a skin irritant for some people.

Fall Planting California Natives

The chill is in the air. At least as I write this. Next week it could return to summer-like weather but for now I’m thinking of what plants I want to add to my garden this fall planting season. California native plants are well suited to planting at this time of year and acclimating to their new homes without much stress. Here are some ideas to get you started.

matilija poppy

By planting from mid-September through mid-November, roots of all plants have a chance to grow during autumn and most of the winter as well without having to supply nourishment to the leafy portion of the plant. Roots of deciduous plants still grow even after plants drop their foliage as long as the ground temperature is above 50 degrees. Cooler day and night temperatures slowly harden off the top of the plant to prepare for the cold days of winter.

Another reason that fall is the no-fail planting season is because plants put in the ground in fall need less water to establish. The plants themselves use less water since photosynthesis is slowed by shorter days even if it’s occasionally hot. Evaporation rates slow down also during fall so moisture in the soil lasts longer as well. Sometimes we get lucky with fall and winter rains perfectly spaced so the ground never completely dries out. I’ve heard rumblings about an El Nino winter but you know how that sometimes goes here in our coastal area.

ribes sanguineum ‘King Edward VII’

Plants that thrive in dry, shady spots benefit especially from fall planting as they need established root systems before next years dry season. Dry shade sometimes occurs in places beyond the reach of the hose but also under native oaks. To protect their health, it’s a requirement that plants underneath thrive with little or no summer irrigation.

Plants of proven success under these conditions include native currants and gooseberry. Ribes sanguinem (red flowering currant) is a show stopper capable of controlling erosion. In the spring the long, flower clusters of this deciduous shrub will dominate your garden. There are many selections of this plant to choose from so if the huge white flowers appeal to you ‘White Icicle’ will be beautiful in your landscape. ‘Barrie Coate’ and ‘King Edward VII’ have spectacular deep red flower clusters and ‘’Spring Showers’’ has 8″ long pink ones. 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, snowberry, matilija poppy and western elderberry. ribes viburnifolium, creeping mahonia and snowberry, baccharis, ceanothus maritimus and Anchor Bay are good groundcover selections.

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 rigida) 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.

Fragrant Plants in the Garden

It was an especially fragrant bouquet of roses on my dining table this week that got me thinking about what an incredible thing our sense of smell is. it’s the only sense that has a direct connection to our brains. We can detect at least a trillion distinct scents. Our scent cells are renewed every 30 to 60 days. Some of the most pleasurable scents, according to recent research, include vanilla, some orange scents, cinnamon, crayons and cookies. I don’t have any crayon or cookie scented flowers but wouldn’t that be a great addition in the garden?

Chinese lilac

Where does fragrance come from? Fragrance in flowers is nature’s ways of encouraging pollination. Just as it draws you to take a deeper whiff, it lures insects to blossoms hidden by leaves and other plants. Some flowers are fragrant only at night and attract only night-flying pollinators like moths, while others are more fragrant only during the day and attract insects like bees and butterflies. The fragrance itself comes from essential oils called attars that vaporize easily and infuse the air with their scents. They are present in different combinations in different plants, but often they are markedly similar which is why there are irises that smell like grapes and roses that smell like licorice.

Pink wisteria

Place sweet-smelling plants where you can enjoy them throughout the season. The potency of flower scents varies greatly, so consider the strength of a fragrance when deciding where to put a plant. Subtle fragrances such as sweet peas. lemon verbenas, scented geraniums and chocolate cosmos smell wonderful right outside the back door. Add stronger scents where people naturally congregate- decks, pools and spa areas, dining alcoves, gazebos. Stargazer lilies, jasmine, lilacs, daphne, citrus and peonies will make your guests linger.

Your front entry should have fragrant plants to greet you when you come home. Train a fragrant climbing rose over a pergola at the gate. Fill some of the containers in your entry with scented bedding plants like dianthus , nemesia, freesias, stock or aromatic evergreens like rosemary and lavender. Plant sweet smelling shrubs like Mexican orange, buddleja, or philadelphus beside a path. Or plant carnations or lavender next to a garden bench or near your hammock.

Brugmanansia

Be sure to include fragrant plants that release their scent in the evening, especially in the areas of the garden you most frequent after dark. Since the majority of night-scented blossoms have white flowers, these plants also light up the landscape at night. Angel trumpet or brugmansia is one such plant as is flowering tobacco and night blooming jessamine.

Several easy-to-grow shrubs have fragrant flowers as an added bonus. Choisya blooms smell like oranges as does pittosporum eugenoides, tenuifolium and tobira. The tiny flower cluster of Fragrant Olive or osmanthus have a delicate apricot fragrance.

Philadelphus lewisii

Other fragrant plants include California native Philadelphus lewisii. Calycanthus occidentals is native to our Central and Northern California mountains. Their fragrant burgundy flowers smell like red wine. Ribes viburnifolium, carpenteria californica and rosa californica are mildly scented, too.

Ideally, when you’ve finished, your garden will smell as intriguing as an expensive perfume. The top note will be floral- jasmine, honeysuckle, rose. The middle register will be spicy, such as the vanilla of heliotrope or purple petunias or the clove of dianthus. Finally, underneath the tones that give perfumes their vigor, like artemisia, sage and santolina.

Not every inch of the garden needs to be fragrant but a waft or two of fragrance from the right plants can turn a garden from ordinary to enchanting.

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

The Dog Days of Summer

They’re called the Dog Days of summer. You know those sultry days with the hottest summer temperatures. The Romans associated the hot weather between July 24th and August 24th with the star Sirius which they considered to be the “Dog Star” because it’s the brightest star in the constellation Canis Major (Large Dog). The Old Farmer’s Almanac uses slightly different dates but the Dog Days of summer are definitely here.

Dahlia- a repeat bloomer

Recently I moved to Bonny Doon where gardening in the hot, sandy soil is very different than the shady clay I was used to. One thing I’ve noticed is the existing drip system has not been modified to allow for the growth of the plants. The emitters which were originally placed at the base of each plant are not even close to covering the current size of the root zone. The crown of the plant is getting overwatered with each cycle but the rest of the plant is bone dry. Time to add more emitters maybe even downsizing to half gallon ones and moving them away from the middle of the plant. No sense wasting water that’s not doing the plant much good.

As summer rolls along you may become more aware of the different microclimates in your garden. With the drier and hotter weather this year some of your plants that used to get along just fine might be showing signs of stress. Taking note of these changes in the performance of your plants is what makes for a more successful landscape. When the weather cools towards the end of September you will want to move or eliminate those plants that aren’t thriving. Be sure to keep a thick layer of mulch on the soil around your plants to conserve that precious water you do allocate to each of your irrigation zones.

Roses with Baby’s Breath- deadhead regularly

The dog days of summer may be affecting our garden but it doesn’t have to stop us from being out in the garden. . The joy of gardening can take many forms including adding a wind chime, bird feeder or bird bath. Groom plants that need some cleanup. Many perennials benefit from a little haircut at this time of year to extend their blooming into the fall season. Santa Barbara daisies fall into this category. Lavenders will keep their compact shape by pruning a third of their branches now. This forces new growth in the center so the plant doesn’t get woody.

Deadhead flowering annuals and perennials as often as you can. Annuals like marigolds, petunias, zinnia and cosmos will stop blooming if you allow them to go to seed. The same is true of repeat blooming perennials like dahlia, scabiosa and lantana.

These plants know they’re on this earth to reproduce. If they get a chance to set seed, the show’s over- they’ve raised their family. Try to remove fading flowers regularly and you’ll be amply rewarded.

Strike it Rich rose

Fertilize shrubs lightly one last time in August or early September. All shrubs, especially broad-leaved evergreens such as rhododendron, pieris, camellia and lilac need to calm down, stop growing and harden off to get ready for the winter cold. Some plants have already set next year’s buds.

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

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