Washington State University Extension

Garden Tips

Archive for October 2012


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

I smiled from ear to ear on a recent shopping trip to one of my favorite garden centers when I noticed some children darting up and down the rows picking out flowers for their garden. Kids interested in gardening is great. Kids excited about gardening is even better.

Adult gardeners innately know the benefits they get from gardening including stress reduction, physical exercise, relaxation, and a way to connect with nature. Add to this a way to express one’s creativity plus realize a sense of accomplishment, the personal benefits of gardening are priceless.

Kids get the same benefits and more. Studies show that children who grow their own fruits and veggies are more likely to eat fresh fruits and veggies and gain a better understanding of a healthy diet. Additional studies indicate that students involved in school gardening activities get higher grades in science studies.

Research also shows that kids involved in gardening projects develop positive social and interpersonal skills and are more likely to have a closer relationship with the parents or adults with whom they garden, developing a greater sense of family and community.

If you ask an adult gardener about their first garden memory, they’ll often relate a fond memory of gardening with a parent or grandparent. Children who garden when they’re young tend to grow into adult gardeners who continue to reap the benefits of gardening. That’s why you should garden with your children or grandchildren… even if it’s just planting a flower in a pot or a tomato in the backyard.

Here are some tips on making gardening fun for children:

The younger the child, the quicker you need to show results to keep their interest. With little ones, plant some radishes. Radishes like Cherry Belle only take a week or so to sprout and just a few more weeks before they’re ready to harvest. Also the seeds are large enough for little hands to handle. Another quick crop is carrots. Orange carrots are good, but a Rainbow Blend of red, purple, white, yellow and orange carrots is super fun. Add to your ‘salad garden’ by growing some leaf lettuce of different textures and colors and finish it off with a sweet cherry tomato like Sun Sugar. They may not like tomatoes, but you might find that they’ll eat these sweet yellow gems.

If you have a sunny spot where you can plant a couple of sunflowers, plant a few seeds of Mammoth Grey Stripe which can reach a height of 6 to 12 feet. You can work in a few math skills by measuring the plants every week to see how much they’ve grown. Once they flower, point out how the flowers turn to face the sun during the day. That’s why they’re called ‘sun flowers.’ If your garden is in a windy spot, you’ll want to stake your sunflowers to keep them from blowing over and dampening your little one’s enthusiasm.

Children delight in picking flowers for someone they love. Give them a little garden space for growing a cutting garden of Sonata Dwarf Cosmos, Petite Mix Marigolds, and Sprite Mix Zinnias.

You can find the different flower and veggie varieties mentioned here from Ed Hume Seeds ( or on seed racks at your local garden stores.

It’s so much fun to garden with children. I’ll be planting sunflowers and zinnias with my granddaughters next weekend.

Published: 6/1/2012 3:09 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

Plant diseases are rife in many local yards and gardens this spring. Our usually dry local climate is not conducive to most fungal and bacterial plant diseases. However, the abnormally wet spring and mild weather this year has led to some diseases running rampant. Of major concern is fire blight on flowering pear, crabapple, and pears trees.

Fire blight is a bacterial disease that commonly attacks pear, flowering pear, apple, and crabapple, but other members of the rose family are also susceptible. This includes cotoneaster, mountain ash, flowering quince, pyracantha, hawthorn and many others.

The first hint that something is wrong is the blackening of twigs and branches. Infected twig tips will droop and bend over to form a ‘shepherd’s crook.’ Fruit that started to develop shrivel and turn black. A closer inspection reveals discolored and blackened bark that moves downward in the twig and branches as the disease progresses.

Fire blight is caused by the bacterium (Erwinia amylovora). It sits quietly during the winter in cankers on host plants just waiting for the right conditions… warm (65 to 80 degrees) moist weather. As the weather warms, the bacteria multiply and form a gummy soup of bacteria that oozes out of cankers and infected tissues. This bacterial ooze spreads to uninfected tissues via insects and water.

Unlike fungi which can make their own way into plant tissues, bacterial diseases like fire blight must find an opening for entry. Frequently fire blight enters through the natural openings in blossoms, getting there on the bodies of insects such as bees, aphids, and ants or via splashing rain or irrigation water. However, the entryway of infection isn’t limited to just blossoms. The bacteria also enters through wounds caused by pruning, hail, and insects and through other natural plant openings.

Severe infections occur when the conditions are just right and the host plants are in full bloom. This year’s ‘perfect storm’ for fire blight happened when flowering pears and crabapples were in bloom.

As soon as fire blight is noticed on a plant, the infected tissues should be pruned out, making pruning cuts well below the visibly infected tissues. How far below? Pruning cuts should be made 12 to 15 inches below any visible signs of the disease. Because the blades of pruners can pick up bacteria and spread it to other parts of the plant, pruning tools should be sterilized after every cut. This is done by soaking the tools in Lysol or a 10 per cent bleach solution. (Note: Bleach is corrosive.)

If you’re successful in saving your tree, you should protect it next year by applying a home garden copper fungicide spray when it’s in full bloom. (Note: Copper sprays will cause russeting on the fruit of Anjou, Comice and Forelle pears.)

There are also some cultural steps you can take to manage fire blight. The disease favors succulent plant tissues, so avoid stimulating excess shoot and sucker growth with heavy applications of fertilizer and water. Heavy or severe pruning during the dormant season also stimulates vigorous growth, so limit major pruning cuts. Since rain and irrigation water can spread the disease, try to keep sprinklers from hitting the tree.

Some varieties of apple, pear, crabapple and flowering pear are more susceptible to fire blight than others. When purchasing these plants, check with your local nursery regarding a variety’s susceptibility to the disease.

I can’t believe how wet our spring weather has been. Enough is enough!

Published: 6/8/2012 2:57 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

‘Midnight marauders’ were the topic of one of my columns a while back. Before I launched an updated version this week, I checked to see when I wrote the previous one. It was in May of 1989. It’s definitely time to bring you up to date on the creatures that plunder our gardens under the cloak of darkness.

If no culprits can be found feeding on damaged plants during the day, the best way to determine what miscreants are at fault is to venture out after dark with a flashlight and catch them in the act. Here are the culprits you’re most likely to find.

SLUGS: Many gardeners new to the area don’t think we have slugs here, but area gardens do host these slimy mollusks that munch on plants at night. Sometimes in early morning you can see a glistening trail of slime that they’ve left behind on plants. Slugs will feed on both the tender leaves of young plants, as well as the tougher leaves of older plants. On older plants their damage is characterized as ragged chewing. On younger plants they devour large parts or entire young seedlings. According to WSU Hortsense, additional evidence of their presence includes ‘pretzel‑shaped’ fecal droppings.

EARWIGS: Most area residents are familiar with earwigs, those reddish brown fast-moving insects about three-quarter inch in length with a set of pincers at the end of their abdomen. During the day they like to hide in dark, moist tight spaces. I suspect they’ll be numerous in area gardens this year because they prosper when spring and early summer weather is wet.

These omnivores are considered beneficial because they feed on insect pests like aphids and mites, but they also feed on tender plant tissues, such as young seedlings and delicate flower petals. They can decimate seedlings, but on older leaves their feeding is characterized by small to large irregular holes and damage along leaf edges. On the surface of ripe soft fruit, including peaches and strawberries, they’ll leave shallow holes. Earwigs also feed on corn silks interfering with kernel formation.

CUTWORMS: Cutworms are the larvae or caterpillars of night flying moths and get their name because some cutworms eat around the base of young plant stems which results in ‘cutting’them off. Cutworms are not remarkable in appearance. They have hairless tan, gray or greenish bodies with various indistinct markings. Ranging from one quarter to one inch in length, they curl up when disturbed. They hide under plant litter, soil, and mulch during the day. Their main source of food is weeds, but they also feed on garden plants.

ROOT WEEVILS: Root weevils are another pesky nighttime insect. The adult weevils are black to brown snout-nosed beetles about one quarter to one half inch in length. Their damage is characterized by notching of leave edges, making them look like someone has cut along the leaf edge with pinking sheers. Root weevils attack over 100 plant species but seem particularly fond of lilac, euonymus, strawberries, peony, rose, rhododendron, and azalea. During the day they hide under plants in loose soil or plant debris.

If you go to bed as soon as the sun sets or you

re nervous about looking for nocturnal pests in your garden after dark, you can try trapping the offenders by placing damp, tightly rolled up newspapers near the plants under attack. Check the traps in the morning for slugs, earwigs or root weevils. Next week we’ll talk about what control approaches work best for these midnight marauders.

Published: 6/15/2012 2:54 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

Last week we talked about ‘midnight marauders,’ garden pests that attack plants at night. This includes slugs, earwigs, and root weevils. Today let’s talk about how to manage them and limit their damage.

Many of these nocturnal pests hide in nearby weeds or under plant debris during the day, so the first step is to tidy up the garden. Get rid of hiding places in and near the garden, such as rocks, boards, clumps of dirts, and plant litter. Remove or mow tall grasses and rogue out weeds in or near the garden.

Welcome birds, spiders, ground beetles, garter snakes, and frogs to your garden. These natural predators can help keep these pests in check. Earwigs and slugs prefer damp conditions. By using drip irrigation in your garden and drying out the soil surface, both can both be discouraged.

If these simple measures fail to keep these pests in check, trapping is a non-chemical control approach to take before using pesticides as a last resort.

SLUGS: Traps are easily created with deep saucers, pie pans, or cans sunk in the ground so the edge of the container is level with the soil. Beer is added to attract slugs withing a few feet or so from the trap. The slugs crawl into the trap and and drown. Remove dead slugs daily and refresh with new beer every few days.

Slugs can also be trapped by placing boards or wet unrolled sections of newspaper down on the soil near damaged plants. Each morning lift them up and handpick any slugs hiding underneath.

EARWIGS: When earwigs have been a significant problem in your garden in past years, frequent shallow cultivation of the soil, especially early in the spring, will disrupt nests and destroy eggs.

Earwigs can be trapped in shallow tuna or cat food cans. Place the clean cans in the garden and fill them with about a half inch of vegetable oil. The earwigs climb in and drown. Make sure the level of the oil is at least one inch below the edge of the container. When full of earwigs, empty and renew the trap. Some gardeners say adding a few drops of molasses on top of the oil makes the traps more attractive to the earwigs.

Another earwig trap consists of loosely rolling up a moistened section of newspaper and securing it with rubber bands. The roll will trap more earwigs if baited with wheat germ or wheat bran before rolling. In the evening, place the moistened rolls out in the garden near damaged plants. In the morning, collect the rolls, seal them in a plastic bag and dispose of them in the garbage. Repeat this nightly for several weeks.

ROOT WEEVILS: A simple method for trapping root weevils is to place a sheet beneath each of the damaged plants in the evening. Then go out well after dark with a flashlight and shake the affected plants. The feeding weevils will drop to the sheet. Collect the weevils and drop them in some soapy water. Do this nightly until you are catching few to no weevils.

LAST RESORT: There are a number of pesticide products available for control of slugs, earwigs, and cutworms in the garden. If you’re using the product in a vegetable garden, make sure it’s recommended for use around food crops. Slug baits containing iron phosphate are effective and less toxic than other baits. Whichever products you select, be sure to read label directions. Note that baits can be attractive to pets. Follow all label precautions to avoid poisoning pets or bees.

Published: 6/22/2012 2:44 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

I’m not quite sure why plant breeders endeavor to create plants with black flowers. Black roses, iris, tulips, orchids, pansies, and petunias… what’s the attraction? Perhaps black flowers are perfect for ‘goth gardeners’ who wear black clothes, gloves, hair and makeup, but what about the everyday gardener. Why black flowers? I suppose it’s the novelty of having a plant with black flowers.

Perplexed about the attraction of black flowers, I’ve decided to give them a try this spring and purchased a new petunia called ‘Black Velvet.’ I have it planted in a black pot with the Proven Winner, Diamond Frost euphorbia. I’ve dubbed the theme of this planter ‘a black tie affair.’

Breeding new colors of petunias isn’t easy. It usually takes about two years of breeding efforts to develop a new color, but Black Velvet took longer. Ball Company breeder, Jianping Ren, took four years to come up with this very dark petunia.

Black Velvet is not a trailing ‘spiller.’ It develops an upright, mounded habit growing from eight to 12 inches high and wide. It’s supposed to bloom early in the season and remain covered with sweet-scented flowers most of the season. Supposedly heat and drought tolerant, it should be easy to grow with no deadheading needed to keep it blooming. Black Velvet’s flowers are described as ‘charcoal black,’ but in bright sunlight you’ll see that they’re actually a very, very deep purple. However, in most light they do indeed look black.

An interesting problem that some gardeners have experienced with this petunia is the development of yellow striping. The Ball Company explains that this can happen especially when there are abrupt changes in the environment, such as suddenly going from cool, cloudy weather to hot, sunny weather or from dry soil to wet soil. Once these conditions even out, the totally black flowers should return. I hope so, because with our fluctuating weather my Black Velvet has developed these yellow stripes.

It’s said that ‘everything goes with black.’ So while I’ve paired my Black Velvet with the delicate lacy white flowers of Diamond Frost euphorbia, combinations with bright pinks, reds, oranges, and yellows promise to be eye-catching.

Breeders have also developed other plants with ‘black’ flowers. There are a number of ‘black’ iris varieties, such Superstition and Black Tie Affair, but these are varying shades of dark purple, not truly black. Dahlias touted as having black flowers, such as Arabian Nights, tend to have dark red to burgundy flowers. The day lily called Starling has deep red to cinnamon brown flowers. The Hollyhock called Jet Black or Nigra has very dark red-brown flowers that are almost black.

Gardeners have long lusted for black roses and black tulips, but have still come up short despite the valiant efforts of plant breeders around the world. Black Baccara, a hybrid tea rose introduced by Meilland in 2000, comes close when the buds first show some color, but the dark buds open to a dark blackberry reddish hue. An interesting rose, but not really black. Queen of the Night, a single late spring tulip, has flowers that look black in the right light, but in bright light their deep maroon color is revealed.

The only other successfully black flower that I’ve seen in addition to the Black Velvet petunia are black pansies. One cultivar that truly looks black is Black Magic. These show up in the fall at local nurseries to be paired with orange pansies for making a container garden with a Halloween theme.

I suppose the great quest for black flowered plants will continue, but I still have to wonder, ‘Why black flowers?’

Published: 6/29/2012 2:40 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

After the 1970s houseplants seemed to lose their appeal for many. Now interest in indoor gardening is on the upswing again. A big part of this reinvigorated trend is indoor orchid culture. You can find flowering orchids for sale in garden centers, big box stores, and even grocery stores. They’re no longer just for expert hobbyists with greenhouses. Everyday gardeners are giving them a try.

If you can provide orchids with the right light and conditions, they’re easy to grow and don’t demand much attention. However, repotting orchids often has the everyday gardener stymied. They aren’t like other houseplants with typical root systems growing in regular potting soil. Most of the orchids sold for household growing are epiphytic plants native to tropical and subtropical regions of the world. Epiphytic means they don’t grow in soil, they grow on the bark of trees.

One of the things novice orchid growers need to know is how to repot plants and the right potting mix to use. Orchids growing indoors in pots, require special potting mixes and pots that provide roots with plenty of air like they get in their natural habitat. Excess moisture and a lack of air leads to root and plant death.

Orchids are typically repotted about every 1 to 2 years. Repotting is necessary either because the plant has outgrown its pot or because the potting media has begun to break down and needs to be replaced. It’s best to repot plants in the spring when they start to put new roots out, but can be done other times of year if necessary.

Potting mixes vary depending on the needs of the orchids and the environment in which they’re growing, but good drainage and aeration are the important factors when deciding what works best. Many commercial mixes contain chopped pine or fir bark, coarse perlite, and charcoal. Before repotting, the media should be rinsed and soaked overnight to allow it time to absorb moisture. It’s also good to water the orchids the night before repotting.

The next day ‘unpot’ the plant and gently remove the old potting media from around the roots. Rinse the roots with clean tepid water and cut off any dead roots. Repot the plant, situating it about a half inch from the top of the pot, filling in around the roots carefully with the new mix. A chopstick can be used to carefully push the media in between the roots. You’ll want to use a bigger pot if the plant appeared to be crawling out of its current pot.

Orchids are sensitive to disease so you should sanitize your work surface, pots, and tools before starting the repotting process. Orchid growers use a commercial sanitizer or a solution of one half cup of bleach per gallon of water. Start with clean hands too.

Unsure about the repotting process? You can get your orchids repotted at the Orchid Show in Kennewick this weekend sponsored by the South Central Washington Orchid Society. The show is being held at the Tri-Tech Skills Center, 5929 West Metaline Ave on Saturday from 11:00 a.m. to 5:00 p.m. and Sunday from 10:00 a.m. to 3:00 p.m. The admission fee is $3.00.

Orchids will be repotted by local experts for $5.00 apiece from 1:00 to 2:00 p.m. on Saturday and from 12:00 to 1:00 p.m. on Sunday. There will also be five commercial orchid vendors selling orchids and orchid growing supplies at the show.

As part of the show, there will be a large display of beautiful orchids grown by local experts and three seminars, ‘Is There a Secret to Growing Orchids in Your Home?’ at 2:00 p.m. on Saturday; ‘Potting Media and Pots for Orchids’ at 3:00 p.m. on Saturday; and ‘Mounting and Growing Orchids Au Naturale’ at 1:00 p.m. on Sunday.

Published: 5/4/2012 2:30 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

One of the most common lawn problems brought into our local WSU Extension Master Gardener Plant Clinic is creeping bentgrass. Lawn owners note that patches of this grass seem to die or turn brown in the middle of summer but then come back again in the fall. The owners also note that when they pull on patches of the grass, it comes up much like a carpet or a loose piece of sod. We like to see samples of the grass to confirm its identification, but the offending grass is usually creeping bentgrass.

Creeping bentgrass is a low-growing, perennial cool-season grass that spreads out horizontally via above ground stems (stolons). These stolons can root where ever they touch the ground, resulting in circular patches of grass that stick out like sore thumbs in the typical Kentucky bluegrass lawn. That’s because the bentgrass has a finer texture and a blue green color that makes the spots obvious, especially when the bentgrass goes dormant and brown during the heat of summer. Walking on large areas of creeping bentgrass feels like you’re walking on a soft carpet. That’s no doubt why another common name for creeping bentgrass is ‘carpet bentgrass.’

Creeping bentgrass is an invasive grass that often shows up in older lawns, especially ones that are watered and fertilized heavily and mowed too short. You might wonder how creeping bentgrass first invades a lawn. Bentgrass can get started via seed in irrigation water or even as a contaminant in the original lawn grass seed. Because creeping bentgrass also reproduces via pieces of the stolons, it can be spread by mowers and other lawn equipment used on bentgrass infested lawns.

When it comes to control of bentgrass Jenny Glass, WSU Plant Diagnostician, notes that ‘there are no “magic bullet” herbicides available for removing one unwanted grass species from the desired types without hurting the wanted turf.’ Because creeping bentgrass has very shallow roots, one approach is to cut small patches out of the lawn using a spading shovel, digging down one to two inches to remove the both the grass and roots. The resulting hole is filled with clean soil and reseeded with grass that matches the rest of the lawn. However, one is seldom able to remove all pieces of bentgrass with digging and it will eventually return in that spot.

The other alternative is treating the bentgrass patches with glyphosate. Glyphosate, the active ingredient in Roundup and other non-selective grass herbicides, kills perennial grasses including the desirable lawn grass. When trying to kill a patch of creeping bentgrass in a lawn with a glyphosate product, the patch as well as an area six inches beyond the patch should be treated. The effective time for treatment is when the grass is green and actively growing in spring or fall, not when it’s brown and dormant in mid-summer. Once the grass in the treated area is dead, rake it out and reseed the spot.

If a creeping bentgrass infestation involves large areas of lawn, not just a few patches, you will need to renovate the entire lawn by killing all the grass and starting over… or you may decide to just live with it.

As with many yard and garden problems, your best defense against a bentgrass infestation is keeping the lawn in a healthy condition with deep, infrequent irrigation, proper fertilization, and mowing the lawn regularly at a height of 2.5 inches.

Need help with a lawn or garden problem? Call the WSU Extension Master Gardener Plant Clinic at 736-2726 Monday through Friday from 9 to 12 and 1 to 4. You can also stop by their table at the Pasco Farmer’s Market on Saturday mornings.

Published: 5/11/2012 2:19 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

When I was growing up, gardeners often grew red zonal geraniums in clay pots on their back stoop. Garden geraniums are more correctly called pelargoniums, but since we’re used to calling them geraniums that’s what I’ll stick with here.

Our garden geraniums are primarily native to South Africa where they’re tender evergreen perennials. However, in our temperate climate they’re grown as annuals, but some gardeners will keep them growing by taking them indoors for the winter.

The zonal geranium is familiar to most gardeners and is popular because it’s both heat and drought tolerant. Thanks to the vigorous hybridizing efforts of plant breeders it has come a long way from the ho-hum back-stoop geranium that our mothers and grandmothers grew.

The still popular zonal geraniums are characterized by the circular zones of color on their leaves ranging from dark green to red to white. The flowers no longer only come in red but are available in a range of different reds, pinks, salmon, purple, orange, and white. Once the only zonals that performed well for gardeners were grown from cuttings, but now a wide variety of magnificent zonals are grown both from seed and cuttings.

Another popular geranium is the Ivy or Ivy Leaf geranium. The name is fitting because they have both ‘ivy’ shaped waxy leaves and tend to have trailing stems which makes them good choices for hanging baskets. Older varieties were difficult for area gardeners to grow because they didn’t do well under hot summer conditions. More recently, breeding efforts using single-flowered European varieties have yielded ivy geraniums with greater heat tolerance. However, these newer ivy geraniums are still not as durable as the zonals and should be kept in cooler locations where they get morning sun and late afternoon shade. Sensitive to widely fluctuating soil moisture, they do best with moderate, even soil moisture.

Martha Washington or Regal geraniums have dark crinkled leaves and beautiful showy pink, burgundy, to lavender flowers. Regals prosper outdoors in climates where summer nighttime temperatures don’t go above 60 degrees. In our region, they’re great as flowering gift plants, but aren’t a wise choice for growing in the garden or outdoor containers because they don’t do well in high heat or sun.

There are also some newer groups of geraniums:

Stellar: Basically these are just zonals with fancy star-shaped multicolored variegated leaves and star-shaped flowers.

Fancy-leaf: Again, these are zonals with ‘fancy’ leaves with bright color zones. They’re grown both for their striking foliage and their flowers.

Scented: It’s not the flowers that are scented, it’s the leaves! You can find scented geraniums with leaves that smell like roses, citrus, mint, coconut, chocolate, nutmeg, apple and spice. Most scented geranium flowers are not spectacular, but these geraniums come in a variety of plant and foliage forms that add interesting texture to container gardens.

Expert Tips for Growing Gorgeous Zonals

1. Grow in full sun.

2. Whether growing in the ground or pots, moderate moisture and good drainage is essential. Geraniums don’t like ‘wet feet.’ When planted in containers, the potting mix should be well aerated. Once established in containers, water only after the top inch of soil becomes dry.

3. Provide adequate nitrogen all season long using a slow-release fertilizer in the potting soil or a water soluble fertilizer every two weeks.

4. Remove spent blooms to encourage new ones and ‘pinch’ stem ends to stimulate bushy side growth.

Enjoy your pelargoniums!

Garden Alert!

Cherry fruit flies and codling moths have emerged and will be starting to attack the fruit of cherries, apples, and pears. Now is the time to start applying regular applications of pesticides to keep your fruit from becoming wormy. For information on what materials can be used, including organic pesticides, go to‑franklin/gardening/plant for the Backyard Fruit Tree Pest Management Charts.

Published: 5/18/2012 2:06 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

The National Garden Bureau has named 2012 as the ‘Year of the Herbs.’ Each year the National Garden Bureau names one vegetable, one flower, and one perennial to be showcased. The honored plants are selected because they’re popular, easy-to-grow, and widely adapted to gardens across the country.

I love garden herbs, but what’s the technical definition of an herb? Holly Shimizu, director of the U.S. Botanic Garden says ‘Herbs are defined as plants valued historically, presently, or potentially for their flavor, fragrance, medicinal qualitites, insecticidal qualities, economic or industrial use, or in the case of dyes, for the coloring material they provide.’ I consider garden herbs to be annual or perennial plants used for fragrance or in flavoring savory or sweet dishes.

Many of the garden herbs that area gardeners can grow prosper in full sun and a well drained soil that’s slightly acid to slightly alkaline. Some herbs like sage, thyme, and lavender thrive under our hot, dry summer conditions. Most herbs don’t grow best in soils high in organic matter or nitrogen, but will benefit from some added compost if the soil is very sandy, compacted or infertile. When it comes to soil moisture, certain herbs like sage, thyme, lavender, and oregano prefer dryer soil conditions and others like lovage, parsley, basil, and cilantro prefer evenly moist soil.

One of my favorite herbs is garden sage (Salvia officinalis). Sage is a strong seasoning used when cooking poultry, sausage, and stuffing. However, it’s flavor is not why sage is my ‘favorite.’ I hold this herb in high esteem because it does double duty for me as a flowering perennial. It dependably produces pretty purple flower spikes that attract birds, bees, and butterflies. The blue-gray sage foliage provides a pleasing contrast to the bright and dark green leaves of plants.

Another perennial herb that I like to grow is rosemary, Rosmarinus officinalis. Rosemary, also a savory herb, is easy to grow. Some cultivars grow into woody shrubs that are trained into large decorative topiary. Unfortunately, most cultivars of rosemary aren’t hardy in our zone. An exception is ‘Arp’ which is quite hardy. Arp grows from three to five feet tall and has tiny light blue flowers.

My other favorite herb is common sweet basil, Ocimum basilicum. Both the flavor and fragrance of basil is heavenly. Because it’s an annual, I like to grow basil in a large pot on my patio. One thing I don’t like about basil is its propensity to go to flower or ‘bolt.’ Once it starts to flower, the production of useful leaves declines along with its flavor. You can keep pinching out the flowers, but it’s usually a losing battle. Your best bet is to select a cultivar that’s slow to ‘bolt.’ Many gardeners favor the Genovese cultivar because of its flavor and it’s slow to bolt.

For the last two years, I’ve also planted ‘Pesto Perpetuo,’ a decorative basil that doesn’t flower, so no pinching is required. ‘Pesto Perpetuo’ grows into a dense, columnar plant reaching a height of two to three feet and a width of only one foot. The bright green variegated leaves contrast well with the darker stems. It has typical sweet basil flavor with a hint of lemon. This coming season I plan to use it in the center of my large flower planters for height.

So now that you know this is ‘The Year of the Herbs,’ honor these flavorful plants by planting your favorites this year.

Published: 1/27/2012 1:24 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

Eager first-time gardeners may be so anxious to start their garden that they fail to take the time to adequately prepare the soil. The key to garden success starts with the soil. If you have bad soil, your success will be limited.

So what’s considered a ‘bad’ soil? Soils that are compacted, or don’t drain well, or drain too well and don’t retain moisture, or don’t contain nutrients are bad soils that need help to become productive.

Organic matter is the magic potion for creating a better soil from bad soil. Organic matter (OM) improves the drainage of compacted or heavy soils by increasing the porosity. It helps sandy soils retain water and nutrients. OM also acts as a slow-release fertilizer over time, releasing nitrogen, phosphorus, and sulfur.

However, OM can turn into ‘bad magic’ if you add too much. Don’t overload the soil by applying more than one to two inches of organic matter before tilling it into the soil. Fall is a good time to add uncomposted OM to your soil, especially when starting a new garden.

The wrong types of OM will can also spell trouble. The microbes in the soil responsible for breaking down organic matter need nitrogen to reproduce. Materials with a high carbon to nitrogen (C:N) ratio will tie up all the available nitrogen. The garden plants will suffer because they can’t get enough nitrogen from the soil for healthy growth. That’s why it’s best not to use straw, straw bedding, sawdust, wood chips, or bark as the source of organic matter because they all have a very high C:N ratio.

Organic matter with a low C:N ration, such as fresh manure and grass clippings, are a good source of nitrogen, but usually aren’t as good in building the soil. Materials with a moderate C:N ratio, such as chopped tree leaves, compost, and cover crops, don’t provide as much nitrogen to plants, but do a better job of adding OM to the soil.

More Bad Magic: When adding manure from a feed lot or dairy barn, be aware that these materials may be high in accumulated salts because of animal urine. Fall is a good time to on to apply manure so winter precipitation can leach salts away.

Health Alert!… More Bad Magic: When adding manures to your vegetable garden, you risk exposing you and your family to E. coli bacteria and other pathogens in the manure. To reduce the risk, WSU recommends against using fresh manures on your garden. If you do use fresh manure on the garden, they recommend waiting 120 days after application before harvesting high risk crops and 90 days before picking harvesting for low risk crops.

High risk crops are those in direct contact with the soil and that are often eaten raw. This includes leafy greens, such as lettuce and spinach; as root vegetables, such as carrots and radishes; and vining crops left to sprawl on the ground, such as melons or cucumbers. Low risk crops are those that don’t touch the ground or that are typically cooked before eating, such as sweet corn, squash, and eggplants.

To minimize the risk it would be best to apply fresh manure to the garden in the fall of the year or use professionally composted manure from a commercial facility where hot composting was practiced.

Keep in mind that organic matter can be the magic potion that transforms a bad soil into a good, but be sure to apply the right kinds of OM, don’t add too much, and be careful when using manures.

UPCOMING CLASS: Marianne Ophardt, WSU Extension Regional Horticulture Specialist, will be teaching a Backyard Composting Workshop on Saturday, April 28 from 9:30 a.m. to noon inside the Highland Grange Hall, 1500 S. Union Street. Participants registering for this free program will receive a free composting bin and book for attending. Seating is limited. For more information or to register, call 735‑3551.

Published: 4/6/2012 9:38 AM

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