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GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published March 13, 2016

When it comes to petunias, I am a sucker for a pretty face, However, while a pretty petunia may pique my interest, I need to know more before I can commit, I need to know if the petunia is both heat tolerant and well-behaved, Can it be counted on for continuous bloom through the season? Will it get leggy in late summer? Is it self-cleaning, not requiring the removal of spent flowers to keep it blooming?

Petunias of yesteryear may have had gorgeous flowers, but they were not impressive once summer heat arrived and flowering slowed to a stop, When the Wave petunias arrived on the market in 1995, I fell in love, They kept on blooming prolifically throughout the summer, producing virtual waves of color, As with any new plant introduction, the available colors of Wave petunias were limited at first, but Ball Seed Company who introduced the Waves soon developed a larger palette of colors.

Since making a big hit with the first Waves, Ball Seed Company has greatly expanded the types and colors of Wave petunias, The original Waves were very vigorous with plants that grew 5″ to 7″ tall and up to 3′ to 4′ wide and worked well for containers and groundcovers, They were followed in 2001 by Tidal Waves, With name a name like that you can imagine these petunias were even bigger, growing up to 5′ wide!

In 2002 Ball introduced Double Waves with double flowers, in 2003 the Easy Waves, and in 2009 Shock Waves with abundant smaller petite flowers. My current favorites are the Easy Waves because of their more controlled mounded-spreading habit, growing 6″ to 12″ tall and 3′ wide, They do not have as much of a tendency to take over a planter and crowd out other flowers, but they still provide plenty of colorful blooms all summer. This year Ball is introducing three new Waves, ‘Easy Wave Pink Passion,’ ‘Easy Wave Silver,’ and ‘Easy Wave Yellow.’ I can not wait to give them a try,

While my first petunia crush was on Wave petunias, there are now other petunias that can turn my head, Supertunias were introduced by Proven Winners in 2006, Supertunias are vigorous, but less aggressive than Wave petunias and do not have the tendency to overwhelm the other plants in a container garden. Supertunias are heat tolerant, blooming throughout the summer, They do not require deadheading, nor do they become leggy late in the season, They vary bit in size, but generally have a compact, mounded habit, growing up to both 2′ tall and wide,

I was thrilled with the ‘Supertunia Raspberry Blast’ that I planted last year, The flowers were a bicolored bright raspberry pink colors, This year Proven Winners is introducing ‘Supertunia Honey’ with flowers that range from yellow, to pinkish-yellow, to an amber honey color, distinctly different from most other petunia colors. Other new Supertunias to check out include ‘Latte’ with creamy white flowers and with brown-purple throats, ‘Picasso in Blue’ with purple-blue flowers with a lime green edges, and ‘Picasso in Burgundy’ along three new members in their charm series with abundant petite blooms.

Surfinia petunias are yet another line of heat tolerant compact trailing petunias and are marketed by Suntory, While Surfinias are the most popular easy-care, heat tolerant petunia in Europe, they have yet to become as popular in the U.S, Suntory touts that their Surfinias do not get leggy like some of the competing trailing petunias and have shorter nodes, larger thicker leaves, and more branching.

Wave, Supertunia, and Superfinia petunias provide summer long color in containers and gardens even during the torrid summer months. I adore them all.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written July 16, 2015


I adore flowering annual plants and have eight large pots lining my patio. They provide delightful color all summer long. However, many annual flowers are not particularly heat tolerant and stop growing and flowering during the hottest part of summer. The trick is selecting only types and cultivars that are heat tolerant.

My top five favorites annuals that do not fail even in hot summer weather are:

Wave Petunias and Others: I admit to being a big fan of Wave petunias and have previously talked about them at length. They still can not be beat for their ability to keep flowering throughout hot summer and early fall weather. I currently favor the Easy Wave petunias because they have a more mounded trailing habit and don’t become as leggy in late summer. They are available in a variety of colors, including pinks, purples, red, burgundy, yellow, coral, plum, and white.

Despite my devotion to Wave petunias, I still like to give other petunias a try. The Charm series from Proven Winners also have excellent heat tolerance and a mounded, trailing habit. I am “charmed” because even though the flowers are relatively small, the plants stay covered with colorful blooms all season long. This year I am growing Rose Blast Charm with bright raspberry and soft pink bicolor flowers. Wow!

Sweet Potatoes: These heat loving vines are prized for the colorful leaves. I tend to stick with the older cultivars, Blackie with dark purple leaves and Margarita with lime-green leaves. However, there a number of newer cultivars, including the Proven Winners Sweet Caroline and Sweet Caroline Sweetheart series. The cultivars in these series come in a variety of foliage colors, including light green, dappled green, yellow-green, bronze, dark purple, and reddish green.

Mealy Cup Sage: While they do not make the color impact of scarlet sage (Salvia splendens), I prefer the very heat tolerant mealy cup sage (Salvia farinacea). They make great upright “thrillers” in containers, are very heat tolerant, and have few pests. Plus, they are a magnet for bees and butterflies. I usually plant mealy cup sage cultivars with purple-blue flowers, but this year I came across one with white flowers called Evolution White, so I decided to give it a try.

Lantana: Not that long ago, I told you that I had discovered the beauty of the many newer cultivars of lantana. It seems like the hotter it is, the better lantana grows. In milder climates lantana is a woody perennial, but in our region they are used as annuals. When plant shopping this year I could only find a few cultivars of the Proven Winners Bandana series. They are all lovely with vibrant yellow, orange, cherry, white or pink flower clusters that open as one color and then the center flowers turn a different color. The Bandito and Lucky lantana series from other companies are also very nice.

Coleus: The fifth on my list of annuals are heat and sun tolerant coleus. Coleus of yesteryear did perform well in heat or full sun. A number of new coleus cultivars are sun tolerant, but they do not stand up well in extreme heat. Plant tags must say “heat tolerant” or I will not buy them. I am growing several of the heat tolerant Proven Winners ColorBlaze coleus series, including Lime Time, Sedona with orange-pink-bronze leaves, and Marooned with dark purple leaves.

Those are my top five. What are yours?


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 9/27/13

Some of you may know that year after year I have raved about the super performance of the “Wave” line of petunias. The Waves are still great, but there are many more petunias that are matching and maybe even surpassing them. I am so excited to tell you about the newest petunias on the market or coming to the market soon.

I am enthralled by the mini-petunias, also known as milliflora petunias . These are petunias with small, petite flowers about 1.5 inches in diameter. I tried two of Proven Winners’ Charm series of mini-petunias in my containers this year. I was astounded at the mass of color these little charmers provided. Pink Charm grows 10 inches tall with a trailing habit up to 48 inches long. The soft pink flowers have white throats and cover the plants with a mass of color. The Charm series is heat and drought tolerant and also includes Sangria Charm with rosy purple flowers, Indigo Charm with purple flowers, and Watermelon Charm with red flowers.

New this year to the Proven Winners’ Supertunia line is Picasso In Pink, joining Pretty Much Picasso already on the market. Both these petunias have a striking chartreuse edge around the flowers, but the new Picasso in Pink is more compact and less vigorous with a more mounded habit.

The “Picassos” aren’t the only line of petunias with green-edged flowers. Just coming on the market is the “Kermit” series from Westflowers. This line includes Baby, Piggy, and Rose with unique pink and green flowers. They are touted as being abundantly floriferous and weather tolerant.

The Kermit petunias were bred by a German breeder who has also developed a line of petunias called “Crazytunias.” One of these is Black Mamba, a black petunia that is said to be one of the best black petunias available because the flowers don’t fade or develop stripes. Another Crazytunia is ‘Cherry Cheesecake’ with an intense red and white candy cane star patterned flower. It will be exciting to see others from this line of unusual petunias.

It took a while for plant breeders to come up with some truly nice yellow petunias, but what about orange? Danziger just might have it with their Cascadias Indian Summer. It’s a vigorous semi-trailing petunia with blooms that open to yellow and then turn to a peachy orange.

First new colors and sizes in petunias and now there is a new shape too! “Sparklers,” the first star-shaped petunias, were introduced by Thompson & Morgan. They recently introduced ‘Sparkler Mixed’ with star-shaped flowers with both pointed petals and leaves. This mix contains flowers in pastel and jewel toned pinks and purple. The plants have a 12″ tall mounding habit and a spread of 14 inches.

I can’t wait to try some of these new petunias and this season isn’t completely over yet!

Published: 9/27/2013 2:10 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
Published 11/9/2012

From time to time I like to check my ’email box’ and share the interesting items I find there. One of the first items I noticed this week was Cool Wave pansies.

Many of you know I am an ardent fan of Wave petunias. Now there are Cool Wave pansies from PanAmerican Seed, the same folks that brought us the Wave petunias. This new line of spreading pansies is the first non-petunia that PanAmerican Seed has judged worthy of their ‘Wave’ brand.

Cool Wave pansies are vigorous spreading pansies that grow to a height of 6 to 8 inches and trail from 24 to 30 inches. The tough well-branched plants are covered with bright 1.5 to 2 inch flowers and stand up well to rain and rough weather. To keep the plants growing and blooming well, they should be fertilized at planting time and regularly through the season.

While many gardeners will probably use Cool Wave pansies in containers as cool-season spring or fall annuals, they’re rated as Zone 5 plants and are hardy enough to overwinter and return the following spring.

The current Cool Wave colors include Yellow (bright golden yellow), White, Frost (white tinged with blue), and Violet Wing (violet and white). Lemon (light yellow) is also available in Cool Wave mixes. These pansies will make great companions for spring flowering bulbs or with flowering kale and mums in fall planters.

Look for Cool Wave plants at your local nurseries. Seed for Cool Wave pansies are available from Park Seed Company at

Another email that caught my attention was about garden clogs. Several months ago I related how important it is to wear garden gloves when working out in the landscape. A gardening friend related that the same goes for wearing the appropriate shoes to keep your feet safe.

While many local gardeners favor simple garden clogs, some with holes that allow for air movement, a sturdier type of garden shoe or clog can provide better protection especially from foot endangering gardening chores like digging, hoeing, mowing, or weed trimming.

Gardengrips are clogs designed for both men and women to protect their feet in the garden. Made by Lawngrips, they have full grain leather uppers with a rubber overtoe to resist water. Their ‘patented Grip-N-Go outsole provides traction on wet grass’ and they have ‘a tough butyl rubber sole that holds up to shovel work.’

Because garden clogs aren’t generally considered stylish, female gardeners might prefer a slightly more attractive clog. Lawngrips also makes an ultra‑light weight gardening clog called the Nimbus and comes pink, purple, or orange. The Nimbus has many of the same features of the Gardengrips and they have a removable, washable and anti‑microbial insole. These ‘provide support and comfort for all‑day gardening.’

So if you’re in the market for a top quality garden clog that protects your feet and keeps them dry when it’s wet out, check out Gardengrips available from and other sellers. Protect those toes!

Published: 11/9/2012 11:39 AM


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

Which is better, Wave petunias or Supertunias? It’s almost like the shoot out at the O.K. Corral, the dueling lines of vigorous hybrid petunias available to gardeners. Neither line of petunias resembles the wimpy petunias of the past that typically faded away as soon as scorching hot summer weather arrived. Both Wave petunias and Supertunias are heat tolerant, blooming all summer long even during hot weather. Both grow best in full sun with evenly moist, well-drained fertile soil. Neither requires deadheading to keep them blooming. Both are vigorous growers that produce oodles of flowers, outperforming the petunias of yesteryear.

Both Wave petunias and Supertunias need a steady supply of nitrogen as they grow. This may be supplied with slow-release fertilizer added to the soil or potting mix before planting or by regular feeding with water soluble or light applications of granular fertilizer.

Developed in Japan by the Ball Horticultural Company, the Wave series of petunias were the first vigorous, heat tolerant hybrid petunias to arrive on garden store shelves over 15 years ago. Low growing and spreading, they were initially developed to be a groundcover type petunia. Propagated from seed, they generally have a sizeable root system.

The Waves are great for use as groundcover type bedding plants or in containers. However, most cultivars are extremely vigorous and can overwhelm and crowd out other plants in container gardens. Because they’re so vigorous, they can become a little leggy in late summer. If they do, cutting them back in early August will renew their appearance for the remainder of the season.

There are now about 55 different cultivars and five main types of Wave petunias. The classic Waves are five to seven inches tall and three to four feet in width. The Easy Waves form one foot tall and three feet wide mounds of color. The Tidal Waves with big flowers reach a height of two feet and a width of five feet and make excellent groundcovers. The Shock Waves are newer additions to the Wave line with smaller flowers and more restrained growth. They’re better suited for smaller spaces. The Double Waves have double flowers and work well as ‘spillers’ in containers and hanging baskets.

Marketed by Proven Winners, the Supertunias are newer arrivals at the garden store. There are about 30 Supertunia cultivars, most growing from six to ten inches tall and trailing to two to three feet in length. The Supertunia Vistas have a mounding, cascading growth habit, growing to two feet both in height and width.

The Supertunias are sterile and are propagated vegetatively from cuttings. They’re not as excessively vigorous as the Waves and work well in hanging baskets or mixed with other plants in containers. They’re less likely to overtake and crowd out other plants.

My favorite Wave is probably one of the originals, Wave Purple Classic. I also like the more restrained Shock Wave Pink Vein (light pink with dark pink-purple veins) and Shock Wave Denim (multi shades of denim blue-purple). Amongst the Supertunias, I especially like the SupertuniaVista Bubblegum (bright pink bubble gum), Supertunia Citrus (bright pastel yellow), and Supertunia Raspberry Blast (striped bright and lighter raspberry pink). One very unique Supertunia is Pretty Much Picasso with violet purple flowers edged with lime green.

So when it comes to a showdown between the Waves and the Supertunias, I can’t decide which is better. It’s up to you to decide who’s the winner for your garden. Look for both types at your local garden store this spring.
Published: 3/16/2012 11:49 AM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

A long time ago I wasn’t a big fan of petunias. The ones I planted tended to do well early in the season, but became leggy and stopped flowering with the heat of summer. It wasn’t until I was given some Wave petunias that I started to consider petunias worthy annual flowers for creating container gardens for high heat situations. The problem with the traditional types of petunias is that they aren’t heat tolerant for the conditions of full sun and high heat found in our region. I appreciate their glorious blooms, but their performance just didn’t encourage me to use them in my planters or garden… until the Wave family of petunias came along.

Wave petunias were developed by the Kirin Brewing Company in Japan and were introduced to US gardeners in 1995 by the Ball Horticultural Company. Plant breeders developed this amazing petunia using a wild petunia native to southern Brazil. Wave Purple was the first of this multi-series family of petunias to reach American gardeners.

Wave petunias are known for their generally aggressive growth and trailing habit. What I like most about the Waves are their tolerance of intense sun and high heat. Waves thrive in heat and full sun, if they have enough water and fertilizer. As I’ve mentioned before, last summer I used Wave Purple petunias in the planters in front of my home. Because the front of the house faces south-southwest, the location is very sunny and hot. The high heat is exacerbated by the surrounding paving and brick. My Wave Purples were glorious, blooming freely from late spring until frost in the fall.

There are many varieties in the five series in the Wave family:

– The Wave Petunia Series have a spreading habit and grow 4 to 6 inches tall and 3 to 4 feet wide. They’re great in gardens as a flowering annual groundcover and in planters. There are six colors: Purple, Blue, Misty Lilac, Lavender, Pink, and Rose.

– The Easy Wave Series have a mounded, spreading habit and grow 6 to 12 inches tall and about 3 feet wide. They work well in containers and garden beds. There are nine colors: Pink, Coral Pink, Shell Pink, Salmon, Mystic Pink, Rosy Dawn, Red, Blue, and White, as well as several selected mixes of these colors.

– The Double Wave Series have a spreading habit and grow 4 to 6 inches tall and 1.5 to 2 feet wide. This is a slightly more compact Wave series with frilly double flowers and dark green leaves. They’re great in hanging baskets and containers. There are eight colors: Blue Vein, Blue Velvet, Lavender, Misty Lilac, Pink, Purple, Rose, and White.

– The Tidal Wave Series needs lots of room to grow with a spreading, upright habit they grow 1.5 to almost 2 feet tall and 2.5 to 5 feet wide. They can be used for a spectacular groundcover, for a large container planting, or even for creating a low flowering hedge. There are four colors: Cherry, Hot Pink, Purple, and Silver along with two color mixes.

– The Shock Wave Series is the newest series of the Wave family and were introduced last year. The plants grow from 7 to 10 inches tall and spread 2.5 to 3 feet wide. Take note that this series has much smaller flowers and more restrained growth. Shock Wave petunias are best used in small baskets or mixed containers, as well in garden beds where space is limited. They come in five colors: Ivory, Pink, Rose, Pink Vein, and Purple and two mixes.

Wave petunias are very easy to grow, but still require some attention from gardeners. They will perform best if they receive at least six hours or more of direct full sun. They don’t like wet feet, so the soil or potting mix should be well drained and not kept excessively wet.

Because Wave petunias are such vigorous growers they’re also “heavy feeders” requiring a steady supply of nitrogen fertilizer. A weekly application of water soluble fertilizer will work or you can provide for their needs with a slow-release fertilizer used according to the label directions. There is no need to “deadhead” or remove spent flowers. Wave petunias usually don’t need to be cut back late in the season, but if they do become too long or a bit leggy they respond well to some trimming.

One problem I do have with the Waves are the colors. To me, their “blue” flowers look purple, their “purple” flowers look fuchsia, their “lilac” looks lavender, and their “lavender” looks pink so don’t buy them based on their color names. Before you buy, check out the flower colors at

The biggest problem I have with Wave petunias is getting the types I want. Big box garden centers and local garden stores don’t carry a wide selection of the many different Waves available and the newest types take a long time to reach us here in Washington. However, I was browsing through my seed catalogs and noticed that Burpee and Park (Geo. W. Park Seed Co., at 800 845-3369 or have seeds of many different Wave petunia varieties. Burpee (W. Atlee Burpee, at 800 888-1447 or also sells plants of some.

Published: 2/7/2009 11:43 AM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

It’s about the time of year when we gardeners start thinking about how our plants will stand up against the winter cold. Will my roses make it through the winter? Will my tender perennials survive? Will my cedar come through the winter unscathed once again? It’s no wonder gardeners talk a lot about the weather, it’s so important to our gardening success. I’ve heard that some long range forecasters are predicting a fairly mild winter with temperatures slightly above normal for our part of Washington, so perhaps we don’t need to worry… but those forecasters might be wrong!

Plants are said to be “hardy” in a region if they can withstand the average minimum temperatures commonly encountered there. The main factor involved in a plant’s survival is its inherited ability to withstand winter cold. It’s in their genes.

Hardy plants go through physiological and biochemical changes during the fall that allow them to survive cold temperatures during the winter. These internal changes are induced by two environmental cues that occur in late summer and early fall… shorter days and cooling temperatures.

Scientists call the internal process a plant goes through to achieve hardiness “acclimation”. As the days grow shorter and the temperatures gradually lower, a plant acclimates and achieves its “maximum hardiness” in mid-winter. In late winter, plants lose hardiness through a process called “deacclimation”. Deacclimation occurs in response to lengthening days and warmer temperatures.

Damage to plant tissues or “winter injury” can occur due to abnormal or untimely temperature fluctuations… or due to a gardener’s ill-advised plant selection or poor gardening habits. Severe cold temperatures in the fall, before plants have been able to achieve their maximum winter hardiness, may cause injury. This occurred in our region in October of 2003 and also in October of 2002. Some plants sustained injury from the severe cold because the temperatures dropped to single digits immediately after a spell of very balmy fall weather… long before the plants had become acclimated and able to withstand such low temperatures. English walnuts and flowering cherry trees were two plants that sustained severe damage.

Plant selection is important too. Plants are said to be “hardy” in an area if they can withstand the average minimum low temperatures for that region. The USDA has developed a map with hardiness zones based on average minimum temperatures. Plants are then rated as to the coldest zone in which they can be grown without worry of winter injury. Our area is primarily in USDA Zone 6 with an average minimum temperature of 0 to -10 degrees Fahrenheit, although there are some warmer spots that are in Zone 7 with a minimum of 1 to 10 degrees Fahrenheit. Nursery care tags will often indicate a plant’s hardiness by providing the USDA Zone information. There are also numerous references that provide hardiness zone designations for specific plants… trees, shrubs, and perennials.

The Sunset Publishing Company (Sunset Western Garden Book and Sunset Magazine) also rate plants for their planting suitability in areas and place them in zones. However, their “climate” zones are based on minimum and maximum temperatures, soil conditions, precipitation, and other environmental growing conditions. Our region is located in Sunset Zones 2 to 3.

Gardeners should also be careful not to stress plants or stimulate plant growth late in the season. Plants stressed from drought, heat, insect infestations or disease are more susceptible to cold temperature damage. Plants stimulated to grow by pruning, fertilizing, and watering heavily late in the growing season will not acclimate well and will be more vulnerable to injury.

So what can a gardener do to protect plants from low temperature damage during the winter? Here are some tips.

1. Select plants that are fully winter hardy in our region… Zone 6. A “borderline” plant that’s only hardy to Zone 7 or 8 may survive several mild winters that might occur in succession. However, it will eventually succumb to damage that will occur in one of our colder winters. Exceptions can be found if plants are situated in milder micro-climates that occur in some spots due to topography, proximity to the river, and exposure in the landscape.

2. Don ‘t fertilize your trees, shrubs, and perennials in late summer or early fall. This stimulates growth that won’t be ready for winter. Note: If tree and shrub roots are located in the lawn area and you’re applying the recommended fall fertilizations for your lawn, you’re probably unwittingly also fertilizing your trees and shrubs.

3. As weather cools and water demands on plants decrease in late summer and early fall, be sure to reduce your watering. Heavy watering in early fall can delay the acclimation process.

4. It’s okay to remove dead, injured, or diseased portions of the plant at any time, but don’t prune your plants heavily in the fall. If you need to do considerable shaping or removal of healthy, live portions of the plant, wait until the plant is dormant. For roses, it’s okay to shorten extra long canes to avoid damage in windy weather, but any extensive pruning should wait until spring.

5. Tender perennials, roses, trees, and shrubs can be mulched to insulate their roots from severe cold temperatures, but don’t apply the mulch too early. Plants need to be exposed to cooler soil temperatures as part of the acclimation process. Don’t apply protective mulches until at least the middle of November.

6. Winter drought can also be a problem in our region. Overcast and sometimes foggy weather can give the illusion of moist conditions. However, we often experience mild, dry, and windy weather that can lead to winter drying and drought stress. If conditions remain dry and mild, it helps to water trees, shrubs, roses, and perennials every three to four weeks.

I don’t know if the weather forecasters are right, but it’s always good to be prepared for cold weather… although I’d much prefer a mild winter! How about you?

Published: 11/6/2004 2:13 PM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

I have raved about Wave petunias since they first arrived on the garden scene in 1995. The first series of Waves caught the eye of gardeners like me because they were vigorous, easy to grow, and outperformed traditional petunias by leaps and bounds… especially during the heat of summer.

PanAmerican Seed company is responsible for the Wave petunias. PanAmerican Seed is an international breeder and producer of F1 and open-pollinated flower seed for bedding plants, pot crops and cut flowers. The first in the Wave series was Wave Purple. It was introduced in 1995 when it was selected as an All-America Selections winner. A single plant of Wave Purple was capable of spreading out to a width of four feet while staying only four to six inches tall. At the time, plants of standard petunias only spread out about a foot or so. Purple Wave’s vigor and prolific production of three-inch purple flowers all season long amazed gardeners. It also stood up well to the hot, stressful conditions of our region.

I had never had much luck with petunias in container gardens or as ground covers, until Wave petunias. Wave petunias are great in hanging baskets, wine barrel planters and other large containers, raised beds, window boxes, and flower beds too. The different Waves include Blue (looks light purple to me), Lavender (purply-pink), Misty Lilac (light lavender), Purple (dark fuchsia with a purple throat), Pink, and Rose. Wave Purple, Lavender, and Blue have all been All-America Sections winners!

The Easy Wave series is a sister to the original Wave series. Outstanding petunias, the Easy Waves are a little more controlled than their “wild” sibling. Still vigorous and easy to grow, the plants quickly reach a spread of three feet in the garden and are a little more mounded in their growth habit, reaching a height of eight to ten inches tall. Abundant large flowers, about three inches in diameter, are produced late into the growing season. The Easy Wave series includes Rosy Dawn (rosy pink with a white throat), The Flag Mix (red, white, and “blue”mix), O Canada Mix (red and white mix), Pink (strong pink), Shell Pink (pretty delicate pink pastel), White, Salmon, Red, Blue (deep purple).

For gardeners who like double petunias, there is the Double Wave Series. They have the same Wave traits of heat tolerance, vigor, and low maintenance, but they also offer glorious double flowers. The plants grow to a spread of two to three feet and a height of four to six inches. The Double Waves include Blue Velvet (a gorgeous deep purple), Blue Vein (a dark lavender with darker purple veins), Lavender (purply pink), Misty Lilac (pink), Pink (an outstanding pink with darker pink veins), Purple (fuchsia), Rose (dark pink with darker pink veins), and White.

Finally there is also the boisterous over-achieving sibling, the Tidal Wave series. Talk about vigor, these petunias have been dubbed “hedgiflora” petunias for their taller growth habit and extreme vigor. When planted two feet apart they will form a ground cover, but when planted even closer together they form a dense mounded “hedge.” The plants first grow outwards and then upwards. They also will supposedly “climb” like a vine if planted in a restricted space with support. The Tidal Waves include Cherry, Hot Pink, Purple (fuchsia), and Silver (white with a purple-veined throat.)

This year there is a new Easy Wave series’ member and two new Easy Wave mixes. The newest member, Coral Reef, is a deep coral color with a small white throat. It’s been mixed with Easy Wave Blue and Shell Pink to create the Beachcomber Mixture. The Easy Wave Tropicana Mixture combines Easy Wave White, Shell Pink, and Rosy Dawn.

Tips on Growing Waves

Grow them where they will get plenty of sun. Six or more hours of direct sunlight are needed for good bloom performance.

Keep the soil evenly moist, being careful not to stress them by letting them go dry or wilt.

Vigorous growers, they need nitrogen for good growth. In planters, you’ll want to use a slow-release fertilizer or a water soluble fertilizer. Apply as recommended on the product label. If the leaves of the petunias start to turn yellow, first check to see if the soil is excessively wet. If saturated soil isn’t the problem, the yellowing may be due to a lack of fertilizer. If this happens in mid to late summer, it probably means your fertilizer has been exhausted. Add a moderate dose of fertilizer to carry the plants through until frost.

Published: 1/27/2007 10:45 AM



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