Monthly Archives: February 2021

allergy-free gardening

Landscaping for the Allergy Sufferer

Don’t blame Acacia for your sneezing

Everybody blames the Acacia tree for their allergies but they are not the real culprits for the allergy sufferer. I didn?t realize just how much redwood pollen is dispersed at this time of year. After those horrific winds a while back my patios were covered with 2 inches of thick yellow redwood ?flowers?. Actually the flowers are the male cone but boy, can they put out the pollen. Ask a friend who is highly allergic just how much her life is affected by our dear redwoods. And because redwoods live in such a narrow band of coast line, there is no allergy shot for those highly affected by them. But back to what you can do in your yard if you suffer from allergies.

Yes, the acacia trees are in full bloom. Being one of the first flowering trees we see they get our attention. Blooming acacias are often blamed as the cause of allergic reactions at this time of year but acacias are largely pollinated by insects and their heavy pollen doesn’t tend to become airborne. It’s the non-showy, quiet plants you have to watch out for. If you?re an allergy sufferer some plants are worse than others for you.

About 25-30 popular landscape plants are responsible for the majority of plant-related allergies in California. During the height of the pollen season- from late February to June- there are often thousands of pollen grains in every cubic meter of air. One can breathe hundreds of them with every breath. Though pollen can travel many miles, the majority tend to stay in the general area of their origin.

Redwoods are wind pollinated. Not good for the allergy sufferer.

Redwoods, oaks, alders, ashes and other wind pollinated trees like olives, birch, box elder, cypress, elm, juniper, maple, fruitless mulberry, pine, walnut, willow and privet are the major source of spring pollen. Most native plants are good in the sneezeless landscape but if you have bad allergies or asthma it best to avoid wind-pollinated ceanothus, elderberry and coffeeberry.

You may not be able to avoid those culprits growing on other properties but you can get the most out of your own backyard by creating a sneezeless landscape. Replacing existing plants may be impractical but planning future plantings with these things in mind will save you a lot of headaches down the road and let you enjoy the sunshine outside in your garden.

Flower type is a good way to judge plants. The best looking flowers usually cause allergy sufferers the fewest problems. Plants with bright, showy flowers are usually pollinated by insects, rather than by the wind. These flowers produce less pollen and their pollen is larger and heavier, sticking to the insect rather than becoming airborne and lead to sneezing, a runny nose and watery eyes.

Some trees that are good for anti-allergy gardens are apple, cherry, dogwood, magnolia, pear and plum. Shrubs like azaleas, boxwood, lilac, rose-of-Sharon, hydrangea and viburnum are also not likely to cause problems. Good flower choices include alyssum, begonia, clematis, columbine, bulbs like crocus, daffodil, hyacinth. Also good are dahlia, daisy, geranium, hosta, impatiens, iris, lily, pansy, petunia, phlox, roses, salvia, snapdragon, sunflower, verbena and zinnia. Lawns of perennial rye grass, blue grass and tall fescue blends are usually OK as they will not flower unless allowed to grow to 12 inches or higher. Bermuda grass, on the other hand, can pollinate when the lawn is very short, sometimes as quickly as a few days after mowing.

We don?t know what?s going to happen rain-wise for us this spring. Symptoms can become worse for the allergy sufferer if the body reacts to the disappearance of the pollen following its initial appearance only to have to have more of it later in the spring. According to Dr. Stanley Fineman, an allergist with the Atlanta Allergy and Asthma Clinic, “You become sensitized to it, so when you’re?re-exposed, you can get an even more violent allergic reaction.”

Here’s to a sneezeless spring for you allergy sufferers.

pruning tips, winter pruning

Pruning Plants in February

My plants are confused. Actually they know exactly what they are doing it?s me that?s confused. The mild winter, so far at least, has encouraged many of my plants normally still dormant at this time of year to start growing for the season. What?s a gardener to do when the roses, fuchsias, oakleaf hydrangeas and many other plants never really went dormant this year? Here are some February tasks that I?m going to be doing.

Cut back woody shrubs to stimulate lush new growth. Trim plants like Mexican bush sage and artemisia to within a few inches of the ground. Don’t use this approach on lavender or ceanothus, though. Lightly prune those after blooming later in the season and don’t cut back to bare wood inside the plant.

Prune fuchsias back by a third and remove dead, crossing branches and interior twiggy growth. Container fuchsias can be cut back to the pot rim. Do this right away if you haven?t already done so. A plant is wasting energy on new growth just to have it trimmed off later.

Cut back hydrangeas stems that bloomed last year and apply a soil acidifier if you want the flowers blue. Although aluminum sulfate is the traditional favorite for quickly acidifying soil it?s not as kind to beneficial soil microorganisms. Coffee grounds, pine needles, peat moss and cottonseed meal are better for your soil.

Miss Kim lilac

Don’t prune spring flowering shrubs like lilac, weigela and spirea or flowering trees such as cherry, plum and crabapple now. These and evergreens like rhododendrons, azaleas and camellias should be pruned after they flower. You can cut some branches while they are blooming to bring into the house for bouquets.

Even if you have pruned your roses be sure to remove old leaves still clinging to the plant even if the leaves look okay now. They will most likely develop fungal spots and diseases later if you don?t. Rake up any debris beneath the plant and discard to eliminate overwintering fungus spores

Roses are super forgiving and you can trim them up again using the following guidelines. The goal is to produce lots of roses not just a few of exhibition size. Aim for a vase-shaped bush with an open center.

Prune old garden roses that bloom once in the spring after flowering. Climbing roses require little pruning. 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 cause the cane to flower along its complete length for a beautiful spring display.

Wait to prune back perennials that may have their new foliage damaged in a late frost. Same goes for shrubs that might have gotten hit by frost. That damaged foliage can protect the plant from further frost damage. Mid-March is the estimated date of hard frost in our area or at least it used to be. We gardeners are always betting Mother Nature will go our way and our efforts will not have gone in vain.

Prune fruit, nut, shade trees and deciduous vines like clematis.

Cut back ornamental grasses if you live where you rarely get frost. I?m pruning California fuchsia, salvia ?Bee?s Bliss? and hummingbird sage now. They look okay now but I want the encourage new, compact growth.

winter flowering plants

Flowering Plants for Wintertime

Daphne odora ‘Maejima’

I had to wait a couple years for my variegated winter daphne to settle in before setting flowers but this year it?s making up for lost time. There?s something special about a plant that will bloom in the depth of winter, hold up to rain and scent the garden all at the same time. With beautiful rosy-pink flower clusters and attractive yellow-margined variegated foliage, daphne make a great foundation plant for dappled shade gardens. They are deer resistant and have low water requirements during the summer. What?s not to love?

Tagetes lemmonii

Yellow is always a cheery color in the garden at any time of year. The deep golden flowers of Mexican marigold or tagetes lemmonii are carried on branch ends sporadically all year, peaking in winter and spring. Finely divided leaves are strongly fragrant when crushed and smell like a blend of marigold, lemon and mint which is why deer avoid them. Prune them lightly to control shape and size. They grows 3-6 ft tall and as wide.

A favorite of birds and indoor floral arrangers is the evergreen mahonia. They are already blooming with cheery, bright yellow flower clusters that will last for months. When each flower sets a purple berry they look like grape clusters. The edible berries make good jelly, too. There are 70 varieties of mahonia including our own native Oregon Grape which grows in the understory of Douglas fir forests. Mahonia aquifolium is resistant to summer drought, tolerates poor soil and doesn?t create a lot of leaf litter.

Helleborus orientalis

Also here in my own garden the hellebore flowers are holding up well. One of my favorites is called Cinnamon Snow but all of the varieties of this buttercup relative accept wind, rain, cold and less than perfect soil while getting by with only moderate watering in the shady summer garden. Deer aren?t attracted to them either.

Recently, after seeing a Pink Australian Fuchsia blooming so profusely despite the rain, I decided to add a variegated variety called Correa ?Wyn?s Wonder? to my own garden. Although not related to hybrid fuchsias, the flowers are similar and their nectar will feed the Anna?s hummingbirds. They grow well in dry shade under oaks are deer resistant and drought tolerant.

Camellia sasanqua

Camellia flowers, thick, tough and full of color, easily sail through winter weather. Camellias bloom for a long time and with so many types you can have one blooming from October all the way through May. This showy evergreen shrub is quite drought tolerant once established. Yes, with some mulch and and a deep soak every so often they require much less irrigation than you?d think. There are even fragrant varieties, such as Pink Yuletide, a sport of the popular red Yuletide.

Pieris japonica variegata

Another tough plant that can take weather extremes is the Lily-of-the-Valley shrub (Pieris japonica). There are many varieties of this early winter bloomer. Some have pure white flowers, other sport various shades of pink or dark rose.
Mine is the smaller variegated foliage model with dainty, drooping clusters of pure white flowers in early spring. Right now it is covered with flower buds so dense that you?d think it was already blooming. The new growth in the spring has a beautiful pink tint. This shrub will hold up to the wildest weather. Another plus for the Lily-of-the-Valley shrub is that is useful for firescaping in the landscape and it isn?t on the menu for deer either.

Other winter blooming plants include abutilon, euroyops, witch hazel, edgeworthia, michelia, loropetalum and grevillea. Driving around I?m seeing that the Saucer Magnolia?s are putting on quite the show this year.

Design trends

Controlling Diseases & Pests on Fruit Trees

Beside dormant spray, good sanitation is one of the best ways to control
diseases in fruit trees

I love it when a nice reader takes the time to call me to suggest a topic they?d like to see me write about or remind them what needs to be done at a certain time of year. Take Helen, who lives in Spring Lakes in Scotts Valley, for instance. Helen told me several years ago that she grows tomatoes in the summer and has 4 fruit trees including a satsuma plum, an espaliered apple and a tangerine. Helen battles peach leaf curl on her plum and coddling moth larvae inside her apples and would like to know exactly what to use and when to control these problems.

I know we?ve had a lot of rain which makes gardening and spraying difficult. You can prevent or control many diseases and overwintering insects by applying a dormant spray this month. This can be the most effective spray of the season. Fungal diseases such as peach leaf curl, fire blight, scab and anthracnose as well as insects including aphids, San Jose scale, bud moth, leaf roller, whitefly larvae, mealybugs and mites can all be controlled by dormant spray and horticultural oil.

There are several types of dormant sprays and all three types are considered organic. Lime-Sulfur or copper can be mixed with horticultural oil which smothers overwintering insects and eggs. This spray is good for all fruit trees except apricots which should be sprayed in the fall with copper and this month only with horticultural oil.

Apply dormant spray when the temperature is above 40 degrees. Make sure you cover every nook and cranny of each branch and trunk until the tree is dripping and spray the surrounding soil. Spray only plants that have suffered from pests or disease. Sprays, even organic, can kill beneficial insects as well. Even though they’re organic, dormant sprays can be irritating to skin and eyes, Wear long sleeves and gloves and eye protection.

Spinosad has been shown to suppress fungal diseases. Do this when the buds swell but before they open. Do not spray 36 hours before rain in predicted. Be sure to spray the ground around each tree.

Spray dormant fruit trees this month before they leaf out to control fungal diseases and insect pests. Coddling moth control starts Mid-March to early April.

Coddling moth control requires a different approach. The larvae of this particular moth is one of the few caterpillars that are likely to be found inside pear or apples. University of California Integrated Pest Management website has complete information about controlling this pest.

The website is http://ipm.ucanr.edu/PMG/PESTNOTES/pn7412.html

The bottom line for coddling moth control is the timing of insecticide spray applications, especially with newer, less toxic pesticides like spinosad. The coddling moth overwinters as full grown larvae within thick silken cocoons under loose scales of bark and in soil or debris around the base of the tree. The larvae emerge as adult moths mid-March to early April. To be effective your spray application must be timed for when when they are active.

Starting three to four weeks after bloom, check fruit at least twice a week looking for the first ?stings? or any mounds of reddish-brown frass. If you scrape the frass away you will see the tiny entry hole where the newly hatched larvae has just entered the fruit. Spray the tree as soon as you see the first sting after removing any fruit with stings as the insecticide won?t kill any larvae that have already entered the fruit. Coddling moths can have three or four generations per year.

According to the website, for most backyard situations, the best course of action might be to combine a variety of non chemical methods and accept the presence of some wormy fruit. Be sure to cut out the damaged portions because they might contain toxins generated by mold.