All posts by Jan Nelson

I am a landscape designer and consultant in the Santa Cruz mountains in California. I write a weekly gardening column for the Press Banner newspaper. I am also a Calif. Advanced Certified Nursery Professional and managed The Plantworks Nursery in Ben Lomond, Ca. for 20 years.

Landscaping for the Allergy sufferer

The heavy pollen of acacia doesn’t become airborne and cause problems for the allergy sufferers contrary to popular belief.

According to historical records for our area the pollen count is mostly moderate in February. Depending on the weather, Pollen.com and Pollenlibrary.com show medium high cunts only for a few days in our area this month. If you’re an allergy sufferer you don’t need a website to tell you what the count is. Our native red alder is in bloom now and it, along juniper and birch, are the main culprits at this time. Grasses, ragweed and other weeds and most trees bloom and shed pollen in March, April and May. Then comes summer, then fall and with it other problems for the allergy sufferer. To further complicate and make matters worse for the allergy sufferer, climate change is making pollen season longer and more intense. You can’t control what’s growing outside your own yard but here are some tips for what to plant and not plant in your garden.

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. Last year after horrific winds in late February and early March my patios were covered with 2 inches of thick yellow redwood “flowers”. Actually the flowers are the male cone and 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 pollens can travel many miles, the majority tend to stay in the general area of their origin.

Although Ca. Native ceanothus are good plants for bees and birds
their wind pollinated flowers aren’t so good for an 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 sneeze-less 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 sneeze-less 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 sneeze-less spring for you allergy sufferers.

How to have a Sense of Place in your garden

Recently I got to enjoy this beautiful October weather walking among the redwoods, mixed oak woodland and open fields watching hawks soar overhead and listening to migrating warblers in the trees.  I was not here in Santa Cruz county, however, but Pt. Reyes National Seashore-a similar but different environment. What struck me was how the gardens of the local residents reflect where they live.  There was a sense of place to the landscaping. 

Our gardens reflect where we live, too.  What can we learn from our surroundings that will help us in our own gardens?

Look to the horizon.  Check views from every possible angel. Borrow scenery if it’s attractive or screen eyesores and distract the eye from them.

Highlight existing features. Develop designs that retain and enhance elements on site like interesting rock formations, meadows, existing trees and native woodland plants.

Consider all aspects of your outdoor space. What are your favorite flower and plant foliage colors?  What patio materials do you like -flagstone, wood, gravel, pavers? What is your favorite season- spring flowering trees and bulbs or fall foliage and berries?  How many hours do you spend enjoying the garden-  sitting, reading, working, relaxing or entertaining?

Whatever landscape design elements you use in your garden, remember they can be broken into smaller parts to make them more manageable- paving this year, planting trees next year, then shrubs, perennials, garden art. Installing a garden is about the journey.  There is never a finishing point.

Important in any design is your choice of trees. More than any other living feature in your landscape, trees contribute to your sense of place. Imaging how different this area would look without the redwoods, spreading oak trees or tall ponderosa pines.

A tree that looks good and thrives in many types of gardens while requiring little summer water once established is the Strawberry tree or arbutus. A relative of the madrone, this evergreen tree is interesting year round. In the fall and winter, clusters of small white or pink, urn-shaped flowers hang from rich, reddish-brown branches with shedding bark. Fruit resembling strawberries ripen in the fall and attract birds. The handsome glossy green leaves emerge from red stems and contrast nicely with the bark, flowers and berriies. Growing to about 25 ft tall they accept full sun or part shade. What’s not to love about a tree with ornamental bark, dainty flowers, decorative edible fruit and handsome foliage?

Another tree to dress your garden for fall is Prairifire flowering crabapple. Birds love the berries and the 1/2 inch fruit remains on the tree for a long time after leaves drop providing food well into winter.  Many of the popular crabapple varieties of the past were highly prone to fungal diseases but this one is among the new disease- resistant varieties now available. Prairifire bloom later than most crabapples with long lasting bright red flowers. Even the red leaves lend color to the garden when they emerge in the spring. If your looking for a small 20 foot ornamental tree with spring flowers and fall berries, this is a good choice for your garden.

Let your landscape express a sense of place to your garden.

Originally posted 2009-10-21 14:38:16.

Shade Gardening ideas

Many of us garden in the shade year round. Other have sun in the summer but shade from fall through spring as the sun’s arc becomes lower. Here are some encouraging tips for you if this describes your garden.

If you’re new to growing vegetables you may be discouraged that your tomatoes are still green. Fear not ! Tomatoes don’t need direct sunshine to ripen , they only need warmth. That’s why green tomatoes will ripen on a kitchen window sill. Don’t be tempted to prune leaves out of the way so whatever sunshine you do get can hit your tomatoes. This can sunburn the fruit if we get a hot day and the result will be a white spot that eventually turns black, hard and inedible.

What about bulbs in the shade? If you dream about drifts of colorful flowers under you trees in the spring but didn’t think they would bloom in the shade, think again . Some bulbs manage to grow just fine beneath trees-even evergreen trees. Many from the daffodil clan, including jonquils and narcissus will grow, bloom and naturalize year after year under tree canopies or other lightly shaded areas. Common ones to try are Golden Harvest, the classic, large yellow King Alfred daffodil and Dutch Master with pure gold flowers. Barret Browning has a soft. butter-yellow corolla and a pumpkin orange frilly tube.

To make sure your bulbs stand out in the landscape, figure at least 20-40 bulbs per drift. Be sure to pick up a sturdy, foot-operated bulb planter to better dig through surface roots and hard ground. In a time when money is short, naturalizing daffodils is an affordable way to grow more flowers and they’ll come back every year without losses from deer and gophers.

Squirrels, mice and moles, however, are observant and crafty. Once they discover newly planted bulbs, they’ll assume it’s food. Just disturbing the earth is a tip off for them. Daffodils and narcissus bulbs are unappetizing but if they dig them up and leave them exposed with just a nibble taken from them, so much for any spring flower display. Protect your bulbs with wire baskets or spray them with foul tasting repellent, letting the spray dry before planting. You can also bury the bulbs with ground up shells.

Planting bulbs along side a path makes for a beautiful look come spring. If you installed a flagstone or stepping stone path or sitting area this fall, now is the best between. Low, sturdy types that can withstand some foot traffic include blue star creeper for regularly irrigated area and creeping, woolly or elfin thyme for drier spaces. Make sure you have enough planting mix between the pavers for the plugs to grow. Fill the largest spaces first and allow them to spread into the little cracks. Mixing groundcover types looks great as long as they have the same water requirements. Low growing pennyroyal and corsican mint smell wonderful when you walk on them as does chamomile, although you need to mow this one occasionally to keep it neat and tidy.

Whatever you choose for your project this fall, you will love the look come spring.
 

Originally posted 2009-10-08 09:26:34.

How to Sow Wildflower Seeds

Gardeners who sow wildflower seeds in the fall may envision a springtime scene of brightly colored blossoms billowing in the breeze with butterflies and bees dancing from bloom to bloom. but sometimes when spring arrives, weeds-not wildflowers steal the show.

The most common mistake when planting wildflower seeds is not getting rid of the existing weed and grass seed that is in the soil and germinate along with the wildflowers. These fast-growing weeds smother the slower growing wildflowers. For a more successful planting, take time to eliminate the competition.

First, choose a site in full sun, To get rid of existing weeds, cultivate the soil 3-4" deep and remove all the weeds. This the the method with the least environmental impact.

The next step is crucial. Soak the soil thoroughly, then wait for the weed seeds to germinate. When they do, lightly cultivate the soil to a depth of not more than 1 inch. Deeper cultivation exposes more weed seeds that will germinate along with the wildflower seeds.

Before sowing the seeds, rake the soil to form shallow grooves. Ensure even distribution of seed by mixing with 4 times its volume of sand and broadcast by hand. Rake the seed lightly into the soil and tamp it for good soil contact. Wait for fall rains to germinate the seeds. You can water to keep the soil moist if rains don’t come.

Next year, when the plants have dried and dropped their seed, .  Be sure to take pictures of your meadow in the spring with the butterflies, bees and birds enjoying it.

Originally posted 2009-10-08 09:08:25.

Pruning Plants in winter

Prune fuchsias back by 1/3. Fuchsias bloom on new wood. Pinch new growth occasionally to encourage more stems.

I’m not sure if it’s me or my plants that are confused. They probably know exactly what they’re doing. That long warm spell at the beginning of January stimulated many of my plants to start growing early. Then the rain and cold arrived. What’s a gardener to do when the roses, fuchsias and many other plants never really became 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 rosemary or ceanothus, though. Lightly prune those after blooming later in the season. If you cut back to the bare wood inside these plants you might lose the whole thing.

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 if it’s trimmed off later.

Now’s the time to prune mophead and paniculate hydrangeas. Oakleaf hydrangea bloom on old wood and should be pruned right after flowering in the fall.

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.

Don’t prune spring flowering shrubs like lilac, weigela, 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. When I grew pruning California fuchsia, salvia ‘Bee’s Bliss’ and hummingbird sage I’d prune now to encourage new, compact growth.

And remember to enjoy your time in the garden. It’s only work if you think of it that way.

Fall Planting ideas

It’s always exciting for me to see the first fall colors of the season. we may not have a show like they do in the the hardwood forests of the east coast but we’re still barbequeing and they’re not. If your garden cries out for a something that you can put a table and chairs under and still have room to play, consider a red maple. Autumn Blaze maples spread to 40 ft. wide and you’ll be enjoying their brilliant orange-red fall color long into the fall season. They need an occasional deep watering like a fruit tree but little pruning.

Take advantage or fall weather to plant cool season flowers.  October is a great month to plant as the plants will have time to become established and start flowering before winter sets in. You’ll be amazed at how much color your plants will produce when you start early. Good choices for this area include iceland poppy, snapdragon, chrysanthemum paludosum, calendula, stock, pansy, viola, primrose and cyclamen.

Originally posted 2009-10-08 09:02:30.