What to Do in the Garden in September

If you want your perennial garden to look like this next year start seeds now.

Now that you’ve treated yourself to a few new un-thirsty perennials that bloom late in the season it’s time to start working on that list of early fall gardens chores. Here are some that might apply to your own garden.

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 infected leaves with organics like insecticidal soap switching to neem oil if they build up a resistance to one of the pesticides.

Plant cool season veggie starts like broccoli, cabbage, cauliflower, chard, lettuce, spinach, brussels sprouts, onions and leeks in soil enriched with 4-6 inches 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.
If you aren’t going to grow vegetables in the garden this fall consider planting a cover crop like crimson clover after you’ve harvested your summer vegetables.

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.

This is also the time to start perennial flowers seeds so that they’ll be mature enough to bloom next year. 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.

Deadhead annuals like this zinnia and perennials for more blooms.

Deadhead flowering annuals and perennials as often as you possibly can. Annuals like zinnias and cosmos will stop blooming if you allow them to go to seed. The same is true of repeat blooming perennials like dahlia, scabiosa, echinacea and lantana. Santa Barbara daisies will bloom late into winter if cut back now.

Fertilize shrubs lightly one last time if you haven’t already done so last month. All shrubs, especially broad-leaved evergreens such as rhododendron, pieris, camellia, hebe, 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 especially appreciate a bit of fertilizer now, encouraging them to bloom another round in October. 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 rose to grow much sooner than if you cut to one with only three leaves. You can always cut lower on the stem if you need to control height.

One last to do: Make a journal entry celebrating the best things about your garden this year.

What to Enjoy in the Garden in September

Echinacea ‘Sunrise Cheyenne Spirit

You 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.

Butterflies, hummingbirds and bees are all attracted to coneflowers.

Daisy flowers always bring a smile to my face. As members of the composite family they have a 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. The clumps spread slowly and can be carefully divided after 3 or 4 years. If faded flowers are left in place, the bristly seed heads provide food for finches in winter.

The herb echinacea is derived from varieties of this flower. Echinacea purpurea and other varieties are used as a fortifier of the immune system, mainly to prevent flu and minor respiratory diseases by increasing the body’s production of interferon. The roots are the part of this plant used for medicinal purposes.

Echinacea was used by Native Americans more than any other plant in the Plains States. It was used to treat snake and insect bites because of its antiseptic properties and to bathe burns. They chewed the plants roots to ease the pain of toothache. It was also used for purification. The leaves and the flowers can be used in teas as well.

Some other perennials to try are agastache or Hummingbird mint. Plant near your organic edible garden to provide nectar for pollinators as well as hummingbirds. The flowers are edible as a salad garnish, in baked goods and in cocktails while their foliage can be added to herb salads or in a cup of tea.

Gloriosa Daisies

I like the bright flowers of Gloriosa Daisy, (rudbeckia) especially the longer lived Goldsturm variety. These perennials make good cut flowers and are tough and easy to grow. They are descended from wild plants native to the eastern U.S. but require only moderate water once established.

Gardening makes us learn new things. If you water less frequently, some plants may decline or even die eventually. Remove those that do and replace them with plants that will thrive with less water.

California Natives for Spectacular Containers

Native Western Azaleas are so fragrant you can enjoy their
sweet and spicy clove scent from a distance.

Adding California natives to my collection of container plants has been a goal for a long time. Besides attracting birds and wildlife to the garden they use less water than most container plants plus they are beautiful.

Gardening in containers is easy. You can control the soil, water and light and the gophers can’t undermine your efforts. There are a lot of California native plants that do well in containers and I’m going to place them where both the birds and I can enjoy them.

Giant Chain Fern are the perfect thriller for a large container in the shade.

For some of my largest containers I’ll choose from natives like Western Azalea (Rhododendron occidentale), Deer Grass, Chaparral Pea or Giant Chain Fern. Any of the taller growing ceanothus and manzanita would look great too by themselves or combined with smaller growing plants.

Penstemon heterophyllus add color to any container.

For small to medium containers I can use Conejo Buckwheat, Hummingbird Mint, Penstemon heterophyllus, Mimulus, Woolly Blue Curls or Coastal Daisy, These combine well with colorful Lewisia, Dog Violets or Wild Strawberry.

I might combine a madrone with a Canyon Gray Coastal Sagebrush (Artemisia californica) which grows about a foot high and will trail over the side of the container adding beautiful gray color to contrast with the rich green of the other leaves. I also like the combination of California Hazelnut, Deer Fern, Redwood Sorrel and Wild Ginger.

Some of the most dramatic containers utilize the concept of combining a thriller, some fillers and spiller or two. Not all my containers will use this formula but I seem to be drawn to those that do. Plants in nature can be quite random in the way they grow together and still be lovely. Containers need a bit more order to dazzle and direct the eye.

Thrillers act as the centerpiece of a container. They are usually big, bold and beautiful. Giant Elk Clover is one such California native that is an attention getter. Chilopsis linearis (Desert Willow) is another great subject for containers as it is slow growing and beautiful in leaf and flower. Other architectural natives that will catch your eye as the centerpiece of a container are Hardy Hibiscus (Rose Mallow) and Pacific Dogwood. The thriller goes in the center of the pot or if your container will be viewed from only one side it goes in the back.

Next come the fillers. They can be foliage or flowering plants but they should complement and not overwhelm your largest plant. Usually they have a mounding shape and I’ll plant several around the thriller. Good fillers include Heuchera maxima and Western Maidenhair fern.

The last plants I’ll add are the spillers which are small and will soften the edge of the container. Redwood Sorrel, Wild Ginger and Miner’s Lettuce are good choices. California Fuchsia would look spectacular with its red or orange flowers and grey foliage spilling down the side of my container.

The best overall soil mix for natives in containers sharp sand and horticultural pumice added to a good potting soil. Never use perlite or that puffed up pumice because it will float and look terrible. Happy Container Gardening

Battling Invasive Plants & Diseases

Improved Meyer Lemons are a cross between a lemon and a mandarin.

I have a nice Improved Meyer lemon tree where I live. Because of water restrictions by the Big Basin Water Company it doesn’t get as much irrigation as I’d like but it still looks pretty good and has quite a few ripening lemons on it. I save water while I’m waiting for the shower to warm up so I can water it and my few fire survivors. I ran across an article recently from the California Department of Food and Agriculture that portions of San Diego and LA counties are still included in the Citrus Greening Disease quarantine area. All this made me think about how creative we are in discovering ways to combat plant diseases and invasive species that impact our food supply.

We’ve all heard stories about detection dogs sniffing out drugs, explosives, cadavers and disaster survivors. In the mid 90’s, handlers started training them for conservation tasks such as sniffing out scat from endangered animal species and detecting trafficked ivory. Now their olfactory prowess is being used in the fight against invasive plants and insects. And dogs are being trained to sniff out Covid 19 odor with 82% accuracy. The list of how man’s best friend is helping us just keeps getting longer.

Although I come across more French broom than Scotch in our area detection dogs can be trained to sniff out all invasive broom. They’re doing this in New York where Scotch broom is just starting to invade and land managers hope to eradicate it before it becomes widespread like it is here and all along the Pacific Northwest. Broom displaces native plants with thickets impenetrable to wildlife and changes the chemistry of the soil around it so that native plants can’t grow there. Broom grows quickly as it is able to fix nitrogen from the air giving a competitive advantage to other non-native weeds. It poses a serious threat to birds, butterflies and biodiversity. Broom contains a high amount of oil, which is flammable and increases the fire hazard. It’s also toxic to livestock and dogs depending on the amount ingested. And those are just some of the reasons why New York wants to keep broom away.

“Our field in the last 15 years has just exploded.” said Pete Coppolillo, executive director of the nonprofit Working Dogs for Conservation in Bozeman, Montana. The organization partners with government agencies, researchers and nonprofits on five continents to provide trained dogs and handlers for conservation projects. Besides helping to detect New York broom they have provided trained dogs to find invasive knapweed in Montana, Chinese bush clover in Iowa, yellow thistle in Colorado as well as invasive zebra and quagga mussels on boats here in California.

Working Dogs for Conservation trains shelter dogs for detection work, screening 1000 dogs for every one they put to work. To make the cut, the dogs have to be not only good sniffers and high-energy, but also seriously obsessed with toys so they’ll stay motivated to work for a reward – the chance to play with a ball.

Because I eat a lot of oranges and lemons I looked up recent papers to see if dogs were still being used to detect citrus greening disease. Sure enough what started 5 years ago with just a few dogs has increased dramatically and many dogs are now being trained. Tim Gottwald, a U.S. Dept. of Agriculture plant pathologist, said during a recent presentation in Riverside that dogs in Florida have been 99% accurate and in tests and just of couple years ago in Southern California backyards, they were more than 92% accurate even when distracted by the homeowners. Because dogs can actually smell the bacteria that causes greening disease within a few weeks after infection well before lab tests can confirm, their work is vitally important.

So when you’re petting “man’s best friend” tonight appreciate all the great things he does for you and for our planet.

Fragrance in the Garden

This dwarf butterfly bush called Buzz Hot Raspberry attracts
butterflies and smells delicious.

A couple years ago I bought a dwarf butterfly bush and planted it in a pot near my entry. It’s one the plants that came back from the roots after the fire and it now lives on my deck but in a new pot. I’m not sure if it’s a Buzz Hot Raspberry or a Lo & Behold Pink Microchip but it’s in full bloom and will continue through fall if I keep it deadheaded. The swallowtail butterflies love it and the scent is so sweet and so strong I can smell it through an open window.

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. Some flowers are fragrant only at night and attract night-flying pollinators like moths, while others are more fragrant 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.

Aroma chemistry is complex and the smell of any flower comes from more than a single chemical compound. These molecules 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. Our noses can detect those chemical compounds that have a major impact on the aroma. Often a particular molecule will make a large contribution.

Some roses, for instance, derive their scent from rose oxide and others from beta-damascenome or rose ketones. These molecules are detectable by our noses at very, very low concentrations. Carnations, violets, lilies, chrysanthemums, hyacinth- all have their own set of compounds that contribute to their scent.

It’s interesting also that as we become accustomed to the same smell our brain phases it out. A compound called ionones, found in violets and rose oil, can essentially short-circuit our sense of smell, binding to the receptors. This shut down is only temporary and the ionones can soon be detected again and registered as a new smell.

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 pea. lemon verbena, scented geranium and chocolate cosmos smell wonderful right outside the back door. Add stronger scents by your deck, pool, spa, dining area or gazebo. Stargazer lilies, jasmine, lilacs, daphne, citrus and peonies will make you want to stay awhile.

Several easy-to-grow shrubs have fragrant flowers as an added bonus. Mexican Orange (choisya ternata) blooms most of the year. Pittosporum eugenoides, tenuifolium and tobira all have tiny blossoms that smell like oranges. too. The tiny flower cluster of Fragrant Olive (osmanthus fragrans) have a delicate apricot fragrance.

Other fragrant plants include California native Philadelphus lewisii (Wild Mock Orange). Calycanthus occidentals (Spice Bush) 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.

In spring there may be nothing quite as spectacular as a wisteria vine, loaded with fragrant purple, pink, blue or white flower clusters, covering an arbor or pergola. Pink jasmine is another vigorous vine with intensely fragrant flowers as is Evergreen Clematis.

Old fashion carnations double the fragrance of nemesia.

I can’t leave out the old fashion border carnation or dianthus. Their clove-scented flowers are born in profusion making them a nice addition to the mixed flower border and containers.

The list goes on and includes scented plants such as nemesia, wallflower, Japanese snowbell, hosta, coneflower, vitex, viburnum, nicotiana, phlox, rose, sweet pea, hyacinth, lilac, flowering crabapple, heliotrope, lavender, sweet alyssum, peony, moon flower, southern magnolia.

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’s Trumpet (brugmansia) is one such plant as is flowering tobacco and night blooming jessamine.

Plant vines for fragrance in your garden. Evergreen clematis (clematis armandii) bloom with showy white fragrant flowers clusters above dark green leaves in the spring. Clematis montana is another variety of clematis that’s covered with vanilla-scented pink flowers in spring also. Carolina jessamine’s fragrant yellow flower clusters appear in masses from late winter into spring.

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.

Growing Bearded Iris

This Zebra variegated bearded iris was blooming at my old house last year. The foliage is growing back since the fire. Their fragrant flowers smell like grape Kool aid.

If you’re in the hunt for an easy-to-grow, drought tolerant, fire resistant, fool proof plant with a flower of such exquisite color, form and knock-your-socks-off beauty, look no farther than the bearded iris. And this is the perfect time to add one or two or twenty to your garden because the Monterey Iris Society is holding their annual sale at the Cabrillo Farmer’s Market this Saturday and next, August 7th and August 14th from 9am – noon.

Several years ago I was fortunate to be able to spend the morning in Scotts Valley painting the tall bearded iris growing at the Cummins Iris Garden. They grow hundreds of varieties on their property. Jim and Irene welcomed my group of fellow artists sharing the history of their property and growing tips. Amidst the beds of prized bearded iris is an impressive antique farming implement collection. This historic property dates back to 1849 when an older house was built as a stagecoach stop where a fresh team of horses could be changed out.

Tall bearded iris grow by an antique farm wagon at the Cummins’ Iris Garden with the watering can collection.

Jim told me that considering the history of the property he and Irene started displaying the old stuff they had and decided to add more by going to auctions and yard sales. Everywhere you look they have created an interesting vignette of plants and artifacts. Displayed on the old barn is an impressive vintage wrench collection as well as dozens of spigot handles. Antique tractor seats, watering cans, washing tubs, rusted bed frames, wagons, old kiddie cars- you name it, Jim and Irene have collected it.

Due to the abundance of old wood on the property Jim said he started building Irene birdhouses. With so many interesting things to enjoy I had a hard time deciding what to paint. I took dozens of photos but settled on capturing their magnificent tall bearded iris in full bloom.

Jim is on the board of the Tall Bearded Iris Society (TBIS) and is also active in Historic Iris Preservation Society. As I walked around the blooming iris beds I noticed many had the name of Joe Ghio as their hybridizer. Some of the Cummins original rhizomes were collected from him as well as other iris gardens in the area. Early on they could only afford to buy a few of the older and less expensive offerings but as their garden began to grow they joined the Monterey Bay Iris Society.

The Cummins iris farm has been so successful that in 2019 the National Convention was hosted at their garden.
When I asked Jim for the growing tips that make his iris so spectacular he told me he mostly uses lawn trimmings and tree leaves along with their native sand to break the soil down. “Iris don’t seem to care much as to soil type, they just need good drainage”, he said. He fertilizes with a balanced granular 15-15-15 fertilizer, using only an 1/8 cup or less sprinkled around each clump around Valentines Day and again in August or September. Another tip he told me was to be sure to plant the rhizomes real shallow with the tops showing and about 12-18 inches apart. They water every 2-3 weeks although he says they can go longer between irrigations.

Every gardener I know raves about their bearded iris collection. By planting early, mid and late varieties you can extend their colorful show for several months. Iris also make good cut flowers and many are fragrant.

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