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.

All Things Blue in the Garden

While harvesting blueberries at a friends’ garden I started thinking of the color blue and why it appeals to all of us gardeners. I was taking care of this fabulous garden while the owners were out of town so I had a lot of time to enjoy all of the plants including the blue flowering ones.

Blueberries-fresh off the bush- delicious

The color blue, especially in the summer, soothes our senses. Soft blues will calm the mind and aid concentration. Strong blues can stimulate clear thoughts. I’m not sure if the different blueberries fall into this category but I sure enjoyed tasting each of them.

Of the 4 different types of blueberries I harvested I think I liked O’Neal, a variety of Southern high bush, the best.
The large light blue early South Moon were also delicious as were the Blueray and Bluecrop. Although many blueberry species are considered self-fertile, all blueberry bushes benefit from cross-pollination and produce larger and more full flavored crops with another bush nearby. To ensure bees carry pollen from one bush to another, space them within 6 feet of each other.

The author’s hydrangea garden

When the weather gets hot I head to the part of my garden where the blue hydrangeas are blooming. I have several mophead types that vary in color from sky blue to deep blue. One is almost blue-violet this year although I didn’t add anything to the soil this winter to make it more acidic. I don’t have any lacecap varieties so I took a cutting of a spectacular Mariesii variegated one at the garden I was tending. It’s the white in both the foliage and the flower that makes the rest of the blue blossoms really standout.

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.

Rose hybridizers striving for true blue have come close by crossbreeding lavender hybrid teas in order to produce offspring having optimum amount of cyanidin, 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.

There are many blue perennials as handsome as they are durable that we can enjoy in our gardens today.
Besides the old fashioned hydrangea, there are violas and campanulas. I”m also growing a blue impatien called ‘Blue Diamond’ that attracts the hummingbirds. All 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.

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. Penstemon heterophyllus, 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.

Increase your Collection of Tall Bearded Iris

Last May I was fortunate to be able to spend the morning in Scotts Valley painting the tall bearded iris growing at Jim and Irene Cummins place. On their property they grow hundreds of varieties and if you are an aficionado of this regal flower you have a chance to add to your collection when the Monterey Bay Iris Society hosts their annual sale. Your first opportunity is at Deer Park in Aptos on August 4th from 9:00-noon and another sale takes place at Cabrillo Farmer’s Market on August 11th also from 9:00-noon.

Joe Ghio 2016 tall bearded iris hybrid

Jim and Irene welcomed my group of fellow artists sharing the history of their property and their 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.

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.

Handmade birdhouses with vintage watering can collection

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 their 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 when the National Convention is being hosted by Region 14 their garden will be one of the host gardens on the tour.

Antique wagon with old milk cans

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.

At the upcoming sales, there will be a “How to Grow Iris” handout available as well as many member of the society available to answer question. At $4 each for these spectacular iris or 20 for $60 adding to or starting an iris collection may just be in your future.