Trouble in Paradise

Aphids on butterfly weed.

Spring around here doesn’t bring a late snow or severe tropical storm that can wreak havoc in a garden. Still we have our own problems that can dash the hopes of even the most optimistic gardener. Is your veggie garden getting attacked by every type of insect and fungal disease lately? Are your beautiful roses looking a bit bedraggle? If your piece of paradise is being devoured or disfigured by insect pests or fungal diseases here’s what can you do about it.

Insects are having a field day at this time of year, too. Put out wet rolled newspaper at night to collect earwigs in the morning. If you see notches on your rose leaves, it’s the work of leaf cutter bees. These guys are beneficial and will go away shortly.

If your rose leaves look like lace then you have the dreaded rose slug. I have a friend whose rose shrubs were really hit by these. It’s discouraging when you had visions of huge fragrant bouquets on every table. What to do?

Rose slugs can skeletonize your leaves in a short time. Treat right away so your roses will look like this.

The rose slug is actually the larvae of a wasp called a sawfly. Because they may have up to 6 generations per year they can do a lot of damage to your roses. Early detection is key. Start scouting for sawfly larvae in early May when they can be hand picked or washed from the leaves with a strong spray. If needed, spray the leaves with neem oil while the larvae are still small. Conventional insecticides are toxic to bees and kill the good bugs too. During the winter rose slugs pupate in the soil and removing a couple of inches will help with controlling their numbers. Even cultivating the soil any time will break up the cocoons.

Keep checking for aphids. They can suck the plant juices from tender new leaves in a short time. They are incredibly prolific. Female aphids can produce 50 to 100 offspring. A newly born aphid becomes a producing adult without about a week and then can produce up to 5 offspring per day for up to 30 days. Yikes, that’s a lot of aphids if you don’t keep up with control. You may be able to dislodge them with a strong spray from the hose. If they persist, spray with organics like insecticidal soap, Neem or horticultural oil. As with all pesticide sprays, do this early in the morning or later then the plant is not in the sun. Be sure to test first to make sure the spray doesn’t burn new growth.

Ants can also bring aphids up into trees and shrubs such as camellias, citrus and roses. The ants feed off the honeydew secreted by aphids, scale and other plant-juice sucking insects. Ants also protect these pests from natural predators. To keep them off, wrap trunks with a 1-2 inch wide strip of masking tape and coast with a sticky barrier like Tanglefoot. Keep the barriers free of dirt and replace when necessary.

A client of mine has a photinia hedge that is not doing well. At first I suspected fireblight as this species is prone to this infections but on closer inspection I found the problem to be leaf spot. The majority of leaf spots are caused by fungi but some are caused by bacteria. Either should be treated with an organic fungicide like Serenade which is non-toxic to bees and beneficial insects, Neem oil, copper or sulfur spray to prevent and control spreading. Affected leaves should be discarded. Many plants get various leaf spots and late spring showers are perfect for them to take hold.

There are so many things that can grow wrong in the vegetable garden, too. Between fungal and bacterial problems, insects, slugs, deer, birds, rodents, rabbits- the list is endless. Keep your eyes open and don’t let a problem become a bigger one with time.

Flowers Make Good Companions

This simple bouquet features smoke bush and phlox.

If you’ve stood in line at a nursery lately you know everyone is doing more gardening these days and that’s a good thing- a very good thing. In addition to growing more edibles be sure to add flowers. Scented flowers attract pollinators to the vegetable garden plus they’re beautiful and lift the spirits during these crazy times.
Last year I was able to purchase huge mixed bouquets from a neighbor. She posted on Facebook when she and her daughters put together lovely arrangements and sold them on the honor system along with eggs in a cooler by their front fence. Whether you have limited sun or lots of it, here are some suggestions to add beauty to your garden.

Roses and alstroemeria in this bouquet.

For starters it’s always good to grow perennial plants that come back every year but self sowing annuals are also great so don’t forget to plant some of those also. Self-sowing annuals that have a long vase life are bachelor buttons, clarkia, cosmos, flax, love-in-a-mist, nasturtium, cleome and calendula. Zinnia, snapdragon, statice, lisianthus and marigolds also make good cut flowers.

In shady gardens, fragrant daphne odora is a wonderful small shrub that provides interesting variegated foliage as well as flowers. Sweet olive (osmanthus fragrans) flowers smell like apricots. Oakleaf hydrangea foliage and flowers look great in bouquets and the leaves turn red in fall which is an added bonus. Our native shrub philadelphus (mock orange) has blossoms that smell like oranges. It will grow in some shade as well as sun. Pittosporum ‘Marjorie Channon’ will add white with a hint of lime to your bouquets.

A mixed bouquet with roses, gerber daisies, carnation, crabapple branches and leather fern.

For sunny spots grow kangaroo paw with their unusual fuzzy tubular flowers. Coreopsis attract butterflies and are long lasting in bouquets. Coneflowers attract butterflies. The showy flowers of alstroemeria attract hummers and butterflies. Dahlias, gloriosa daisy, delphinium, foxglove, scabiosa, aster, shasta daisy and yarrow also make good cut flowers. Penstemon are good for cutting and the tubular flowers attract hummingbirds.

Native flowers that last for a week or more in a bouquet include clarkia and sticky monkeyflower. Yarrow and hummingbird sage will last 4-6 days in a vase. Our native shrub philadelphus, also called mock orange, has flowers that smell like oranges and will grow in some shade as well as sun. Lewisia bloom spring and summer, California poppy and Pacific Coast Iris are beautiful in a mixed bouquet as well.

The secret to a fabulous bouquet is not just the flowers but the interesting foliage and that is something we all have in our gardens. Foliage from shrubs such as abelia, breath of heaven, California. bay, ornamental grasses, grapes and other vines, herbs, woody tree branches like smoke tree and Japanese maple also look handsome in a bouquet.

A Filoli Garden bouquet photographed a couple years ago.

To make cut flowers last, pick them early in the morning before they are stressed by heat. Pull off any foliage or flowers that will be below the water level in the vase. Fill a clean vase with 3 parts lukewarm water mixed with 1 part lemon-lime soda, 1 teaspoon vinegar and a crushed aspirin. Another recipe for floral food is 2 teaspoons sugar, 2 tablespoons white vinegar and 1/2 teaspoon bleach in 1 quart water. The sugar helps buds open and last longer, the acid improves water flow in the stems and the bleach reduces the growth of bacteria and fungus. Change the water and recut the stems every few days to enjoy your bouquet for a week or even longer.

What’s Not to Love about Ceanothus?

Ceanothus growing near the Covered Bridge in Felton

They grow quietly for most of the year – their seed feeding many kinds of birds, their flowers providing nectar for hummingbirds and bees and their foliage offering good nesting sites. They’re fast growing, fragrant, beautiful and they’re in full bloom right now.

If I had to choose one plant to grow that would provide the most benefit for all wildlife it would be ceanothus. Hands down, it’s the best and here are some of my favorite varieties.

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. And maritimus ‘Valley Violet’ is another great looking deer tolerant groundcover, too. Most of these types grow quite wide and are good for erosion control.

One of the upright types I have is ceanothus thyrsiflorus. It’s one of the earliest native shrubs to bloom in our area, is fragrant and self sows. 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 friend of mine grew a new cultivar – ceanothus ‘Celestial Blue’ – with flowers that looked like blueberry sherbet. With a light fragrance, described as grape tart, it made a good screen. 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.

Another cultivar I often use when designing a garden is Ceanothus ‘Concha’ because it will accept summer water more forgivingly than most, tolerate clay soil more than other species and is possibly one of the most beautiful species you can grow in your garden.

Carmel Creeper ceanothus

But are “nativars” as good for wildlife as wild types for the ecosystem? Well, it depends. More on this in another column. It’s complicated.

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 20-25 years although some live longer. There are some on my property that are older. These receive no summer water although I have some that are at least 15 years old that get occasional summer irrigation, so go figure. I’ll keep you posted when they pass.

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 and they grow so fast. Adding fertilizer kilsl 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.

The Art of Forest Bathing

My local trail on a foggy day

I started this Shelter in Place with the best of intentions. The first week I had a daily “to-do” list which included such lofty aspirations as meditation, cooking something new and healthy from the pantry, stretching, drawing and painting, deep cleaning the house, transplanting those overgrown pots. “I can do this.” I said to myself. After all, there are dozens of Zoom classes and You Tube videos in my inbox to explore and motivate me. Well, I can tell you now that after years of wanting to deep clean the house but lacking the time, I discovered this week that wasn’t the reason. We end up spending our time on what matters to us and actually I’ve gotten to most of the “to do” list although it’s taken me since March 18th to accomplish. What I didn’t need motivation for was to walk quietly nearby in the forest.

You know the feeling you get when you are out walking slowly in the forest, stopping to admire a wildflower or mushroom that catches your eye? You know it’s good for the mind and body, but why? It turns out that there are more benefits to being out in nature than the calmness it brings.

My dog Sherman enjoying a slow walk in the forest

Having a dog gives me a reason to be out on the trail. Being out in my garden simply enjoying the birds and flowers also promotes health and studies have shown that spending time in natural environments lowers our stress levels and improves our memory.

Apparently what we take for granted living where we do is all the rage for city dwellers with high stress lives. The idea is simple. Spending time in a natural area and walking in a relaxed way is calming, rejuvenating and restorative.

In the past several decades there have been many scientific studies that demonstrate the mechanisms behind the healing effects of simply being in natural areas. Many of the benefits from the forest actually come from the air. Trees give off phytoncides, such as alpha-pinene and d-limonene, which are volatile organic compounds or aerosols. These compounds protect the trees and plants from insects and disease, but they also benefit us.

Forest bathing is what the Japanese call it. Shinrin-yoku is their term that means “taking in the forest atmosphere.” Forest therapy has roots in many cultures throughout history. John Muir wrote that “Wilderness is a necessity.” Scientists is Japan are measuring what’s actually happening to our cells and neurons.

Forest bathing with Sherman

Trees give off organic compounds that support our immune systems and help our system fight cancer. Other scientifically proven benefits of forest bathing include reducing blood pressure, accelerating recovery from surgery or illness, improving sleep and our mood and reducing stress. Forest bathing lowers our heart rate and lowers levels of the stress hormone cortisol. Soaking in the forest air increases our NK or natural killer cells by about 50 percent.

All I know is that when Sherman and I are out in the garden or strolling in the forest we feel good. We stop to watch the progress of a banana slug. We listen for new bird calls. And as a garden designer I strive to create a space for clients that brings that feeling to them whenever they are outside.

Part of of that good feeling we get being outside has to do with the color green. Green is the color of spring, of growth, renewal and rebirth. It renews and restores depleted energy. It’s a positive color and increases our feelings of relaxation and calmness. Often I get a request for including the color green in a client’s plant palette. We tend to overlook it’s value.

If you don’t have a forest of your own bring that forest feeling to your own garden. Stroll in a relaxed way without thinking about weeds or pruning or other items on your to-do list.

Every Garden Deserves a Dogwood

Eastern dogwood growing near my house in half day sun.

The dogwoods are blooming. Dogwood are a good tree choice for the allergy sufferer as their pollen is not wind borne. Their showy flowers, which are actually bracts, are pollinated by insects. Their pollen is large and heavy, sticking to insects rather than becoming airborne and leading to sneezing, runny noses and watery eyes.

There are four main species of dogwood trees. From the Himalayas in China comes cornus capitata. Korea is home to cornus kousa. Cornus florida is native to the east coast and the west coast is home to cornus nuttallii or the Western dogwood.

Our native Western dogwood is unfortunately prone to leaf spot fungal diseases when grown out of their range. They are a little temperamental in the garden before they reach the age of 10 years but after that they tolerate seasonal flooding and flower and grow with little care in morning sun or light shade.

Cherokee Chief flowering dogwood

We are all familiar with the Eastern dogwood (cornus florida) that’s blooming now. With various shades of pink, red or white blossoms they are stunning. Take note that their root system is prone to disease if not grown with good drainage.

The kousa dogwood is a more drought tolerant, disease resistant and a tougher plant all around. Large, showy flowers open after the tree has leafed out and remain for a long time. This makes it good for hybridizing with other varieties.

The Stella series is a mix of a florida on kousa dogwood rootstock. Vesuvius series is a cross of our native nuttallii with a florida as is Eddie’s White Wonder. There is also a nuttallii-kousa cross called Venus that displays huge flowers and gets its disease resistance from the kousa roots. All these cultivars strive to produce a tree with superior disease resistance and huge, long lasting blooms.

Evergreen cornus capitata ‘Mountain Moon’

Deciduous dogwoods don’t like wet feet especially in the winter. That’s how they develop fungal disease. But there’s an evergreen dogwood that can handle moisture all year round. Cornus capitata ‘Mountain Moon’ is a tough tree that can handle strong winds and isn’t bothered by any pests or diseases. They enjoy lots of organic matter as do all dogwoods. Huge flowers up to 6” wide can last from late spring into early summer. After flowering, the fruits begin to form and grow into red balls about the size of large strawberries. This is the reason is it also known as the Himalayan Strawberry Tree.

Dogwoods attract a variety of wildlife. All sorts of critters use this tree for food and shelter. The giant silk moth and several species of butterflies favor dogwoods as host plants. The spring flowers provide nectar to bees and other pollinating insects. Robin and sparrow are just two of the bird species than build nests on the horizontal branches and many others seek shelter in the leaves. The high calcium, high fat, fleshy red fruits are eaten by 35 species of birds including titmice, juncos and waxwings.

Many people think of dogwoods as an understory tree but this location is often too shady. Grow them in a full or partial sun location that gets afternoon shade after 4:00 PM. Add a couple of extra drip emitters or inline drip tubing to your irrigation system and they’ll be happy.