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NEW AND IMPROVED SHRUBS FOR HOME LANDSCAPES

GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published May 8, 2016

Flowering shrubs were once a staple of home landscapes, but over time they have lost their fan base. Reasons for this loss of popularity may have been their large size and limited seasonal interest. I can recall the Vanhoutte spirea (S. x vanhouttei) in the front of the house where I grew up. In spring it was magnificent when covered with clusters of small white flowers, but the rest of the year it was unremarkable except for its huge size, growing 5′ to 8′ tall and 7′ to 10′ feet wide.

Today, plant purveyors are continually working to offer new flowering and evergreen shrubs for the home landscapes. Many of these are more compact and have multi-seasonal interest, such as springtime flowers, bright fall color, or interesting bark. Other desirable traits include prolonged or repeat bloom, remarkable foliage colors and textures, low maintenance requirements, and pest resistance. Every year I get excited about all the new shrubs being introduced to gardeners and this year is no exception. Here are just a few.

First Editions® Spring Lace Viburnum is being offered by Bailey Nurseries. Viburnums are one of my favorite shrubs, but most tend to be too large for my landscape. However, I might consider planting Spring Lace because it grows only 5′ tall and wide, has dark green leaves that turn dark red in fall, and is covered with flat clusters of fragrant white blooms in spring. Bailey Nurseries says it appears to be fruitless.

I also fondly remember a yellow climbing rose that grew in my grandparents’ yard. It grew very tall and bloomed only once in early summer. Ball Ornamentals is introducing a new series of climbing roses, the Starlet Beauty™ Series, for use in small garden spaces and in patio containers. Ball describes this series as the “elegant little sister of the large-flowered classic climbing roses.” Mauve, pink, ruby or tangerine colored double blooms are produced all season long. Ball touts that the plants are well branched growing 8′ to 10′ tall and 3′ to 4′ wide and can be trained to grow vertically or horizontally on a trellis.

When it comes to boxwood, I am not a big fan because of its odiferous foliage and vulnerability to winter sunburn damage. However, its compact growth works well in more formal landscapes and gardens. Monrovia is introducing Petite Pillar™ Dwarf Boxwood. It is a dwarf columnar boxwood that grows only 2′ to 3′ tall and 2′ wide at the base. Monrovia notes that Petite Pillar can be utilized effectively in containers, in limited space landscapes, or for creating small hedges. It does not need regular shearing to keep it neat and compact.

Every year Proven Winners introduces a bunch of interesting new shrubs. This year one new introduction is a cute little viburnum that will fit into any landscape. ‘Lil’ Ditty’ is a fragrant dwarf viburnum that only grows up to 2′ tall and wide with a mounded form. The creamy white flowers are produced in late spring and may yield a crop of showy black fruit if a pollinator is nearby. Speaking of small, Proven Winners also markets a diminutive forsythia, Show Off® Sugar Baby. It is perfect for the smaller spaces in today’s home landscapes, growing only 18″ to 30″ tall and wide with a mounded form and covered with bright yellow flowers in the spring. It does not require heavy annual pruning.

KEEP SPRING FLOWERING SHRUBS BLOOMING WITH PRUNING

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – MAY16, 2014

KEEP SPRING FLOWERING SHRUBS BLOOMING WITH PRUNING

Last weekend I took advantage of the nice weather to prune my forsythia that was seriously crowding nearby plants. I hadn’t pruned it much for the last two years and it was becoming unruly. It put on a beautiful show of blooms this spring, but I knew that if I didn’t get in there and remove some of the old wood it probably would not have as many flowers next year.

My approach was to go in and remove one-third to one-fourth of the older (thickest stems with side shoots) stems down to the ground. A healthy forsythia is a vigorous shrub that sends up new stems each year that bloom the following spring. Removal of the oldest stems should be done right after flowering because the flower buds for next spring are formed on the new wood by early summer. Pruning later in the season or in winter will reduce the potential flower display next spring.

Occasionally, one or more forsythia stems grow rather long, giving the shrub a rangy, wild appearance. If not an older stem that should be removed, I cut the stem back to a side branch to shorten it.

A weigela was one of the plants being crowded by the forsythia. I planted it in early summer two years ago and initially it benefitted from the shade the forsythia provided, but now it needs more light. I also have two mature weigela shrubs elsewhere in my landscape.

One of these weigelas is ‘Wine and Roses’ with dark burgundy leaves and dark pink flowers. It has prospered in its spot but now it has become a bit bedraggled and there are a number of dead twigs and branches throughout. Since weigelas are prone to winter dieback, this may have been caused by the sudden cold snap last fall. The dieback could also be related to the increasing amount of shade provided by two trees on that side of the yard. Weigelas do best in full sun and will become straggly if located in shade or crowded by other plants.

Perhaps I should just remove it and plant a more shade tolerant shrub, but I think I will see if I can revitalize it first. As soon as it is done blooming, I am going to prune out the thickest, oldest stems along with any of the dead branches and twigs. To shape it up a bit, I plan to selectively prune back any overly long stems to a side branch, being sure not to remove more than one-third of the stem.

Most other multi-stemmed spring-flowering deciduous shrubs are also pruned right after flowering. This is because they too flower on wood produced the previous growing season. These shrubs include forsythia, weigela, lilac, viburnum, honeysuckle, mock orange, Nanking cherry, flowering quince, white-flowered spireas, beautybush, and deutzia. Like forsythia and weigela, one-fourth to one-third of the oldest wood should be removed back to the ground each year.

As part of your pruning tasks, you should also “deadhead” or snip off the spent flowers or seed-heads from the stems you don’t remove. This will give the shrub a tidier appearance and allow its energy to go into plant growth rather than seed development.

It really does not take much time or effort to keep spring flowering shrubs looking their best. Give it a try. Sometime soon we can chat about pruning summer flowering shrubs.

Published: 5/16/2014 11:48 AM

NOW IS A GOOD TIME TO CONSIDER LANDSCAPE CHANGES

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 2/28/14

I was so excited when dwarf re-blooming lilacs were first introduced. I planted several in my yard. They grew well and bloomed, but their display was never remarkable and the shrubs were unattractive. Last year I took out all but one and plan to remove the remaining one this spring. This leaves me still yearning for a pretty, fragrant lilac that doesn=t get too big.

Maybe I should try one of the hybrid lilacs in the >Fairytale= series. Unlike the standard lilacs that grow to a height of 10 to 15 feet tall, Bailey Nurseries has introduced several dwarf hybrid lilacs. The one in the series that has piqued my interest is >Sugar Plum Fairy=. The most compact in the Fairytale series, it grows to a height and width of only 4 to 5 feet and produces fragrant rosy-lilac flowers. Other Afairies@ in the series includes Thumbelina, Tinkerbelle, and Prince Charming. All are very hardy and require full sun for good bloom.

I have always wanted to give mockorange (also known as Philadelphus) a try because when it blooms it is covered with pretty white flowers that give off a wonderful sweet orange fragrance. However, the large size (10 to 12 feet tall) of the traditional mockorange shrubs has held me back. The First Editions Program introduced >Snowwhite Fantasy= in 2011. It is a smaller mockorange, growing to a height of 5 to 6 feet and blooming both in spring and again in summer, producing pretty blowsy 2-inch double flowers.

While smaller than the traditional mockoranges, >Snowwhite Fantasy= is still too big for my landscape. A better fit would be >Miniature Snowflake

, a dwarf mockorange that only grows to a height and width of 2.5 to 3 feet with a compact, mounded habit. The double white flowers are produced in early summer.

There are other small shrubs to consider. I am drawn to the smallest dwarf shrubs being introduced by Spring Meadow Nursery. They are great for tucking into smaller landscapes or even perennial flower beds. >Tiny Wine= is one of these. This is a new dwarf ninebark (Physocarpus) that reaches a height of only 3 to 4 feet. It is the smallest ninebark available and is a compact bushy shrub with dark bronze-maroon leaves and dainty white flowers. Also in the Atiny@ category is a mountain hydrangea called Tiny Tuff Stuff . It grows to a truly tiny 1.5 to 2 feet tall and wide. The lace-cap flowers range in color from a soft lavender blue, to pink, to white.

Also in the diminutive category is Spring Meadow=s Lo & Behold >Pink Micro Chip= a new butterfly bush (Buddleia) that grows to a height of only 18 to 24 inches and gives forth an abundance of flower spikes full of tiny pink blooms. This compact little bush is non-invasive, drought tolerant, heat tolerant, and long blooming. The flowers attract butterflies, hummingbirds, and bees.

With spring right around the corner, now is a great time to consider changes to your landscape plantings. What doesn=t work for you? What would you like to try? It may be hard to decide a plant must go, but why stick with an eyesore or a maintenance headache? Removal gives you the chance to try something new that will hopefully add to the beauty of your landscape.

REMINDER: Gardeners with spring fever should consider attending the WSU Extension=s Spring Garden Day workshop on March 8th. The day-long program starts with keynote presentations about butterflies and bees. These will be followed by a variety of gardening classes presented by WSU Master Gardeners and other local gardening experts. The cost of the program is $20. If you are interested in attending, call 509-735-3551.

Published: 2/28/2014 10:08 AM

YELLOW LEAVES ADD PIZZAZZ

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

I’ve found that over time personal likes and dislikes can change. I used to dislike any plants with “abnormally” colored foliage. In my opinion landscape plants were supposed to have dark green leaves during the growing season, not chartreuse, yellow, purple, brown, red, or orange leaves. Now I’m starting to change my mind.

Except for repeat bloomers, flowering shrubs provide color interest in the landscape over a relatively short period of time. The rest of the season they don’t provide much pizzazz unless they have a contrasting leaf color, interesting texture, or bright fall color.

Last year, I planted a Sutherland Gold elderberry (Sambucus racemosa) with bright golden yellow, finely dissected leaves. It’s on the northeast side of the house and it seems to glow in the shade with it’s cheery foliage. An elderberry with dark purple leaves or a Japanese maple with red leaves would not light up the bed like that cut-leaved golden elderberry does. This plant was developed in Canada and will probably perform best in our area if protected from afternoon sun and heat. I can’t wait for it to get a little larger and start producing bright red berries.

In another bed with full sun and a southwestern exposure, I have a number of plants with plain green leaves. To liven it up a bit, I planted one Emerald

n Gold wintercreeper (Euonymus fortunei) with green and gold variegated leaves. For more contrast in the bed, I’m replacing a plant that died over the winter with a new spirea, Double Play Big Bang (Spirarea japonica). When it first leafs out in the spring the leaves are tinted orange, turning to bright yellow in the summer and then to gold in the fall. It also produces large pink flower clusters in summer.

Hopefully, Double Play Big Bang (2-3

) will be able to endure the heat and sun in that location. There’s also the smaller Double Play Gold (16-24″) with yellow leaves and pink flowers that I could consider. These are two of the newest additions to a number of other yellow to gold leaved spiraea already available, such as Golden Elf, Golden Globe, Goldmound, Goldflame, and Golden Sunrise.

I considered planting a yellow leaved Caryopteris (Caryopteris incana), also known as bluebeard or blue mist, but I have two other Caryopteris in the same landscape bed. They have green leaves and their bright blue flowers add a note of color to the landscape late in the season. They’re very easy care plants with pruning them back almost to the ground every spring. Sunshine Blue (3-4

) and Lil’ Miss Sunshine (3

) with bright yellow leaves and deep blue-purple flowers are the newest of the yellow leaved Caryopteris, improvements over the older Worcester Gold.

There are other shrubs and perennials which can liven up landscape and garden beds with yellow, golden or chartreuse foliage. Check to see which ones at your favorite local nursery appeal to you. Before you buy, I have two cautions for you. First, some of these plants may not bear the intensity of exposure to full sun in our area. Check with the nursery to see if the plants you’re considering fit well with your situation. Second, a little splash of yellow can go a long way. Too many yellow, chartreuse, or differently colored plants will create a busy landscape that looks a little sick.

Published: 5/22/2010 1:43 PM

STOP AND GO, GO, GO FOR GARDENERS THIS SPRING

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

Go. Go. Go. Stop. The very mild spring weather that we have experienced over the last month has plants and gardeners getting ready to go, but some recent cold nights may be putting the breaks on a bit. I’m always wary of early warm spring weather, because weather has a way of changing very abruptly. However, the tenuous forecast for the remainder of the month indicates daytime temperatures in the 60 degree range and nighttime lows above freezing. Based on this forecast, gardeners can get going.

Crabgrass Preventer or Pre-emergent Herbicide: The time to apply these “preventer” type materials is before crabgrass germinates. When crabgrass germinates is dependent upon the temperature of the top inch of soil. Germination occurs when the daytime and nighttime soil temperature reaches 55 to 60 degrees and stays there for about a week.

We often tell gardeners to wait until area Forsythia is in bloom for several weeks before applying a preventer material. However, this bright yellow flowering shrub is what’s called a phenological indicator. It blooms when soil temperatures are approaching that 60 degree range. An inexpensive soil thermometer is a more accurate way to determine if it’s “time”.

So why do we dither so much over when it’s time to apply “crabgrass preventers” every spring? University research indicates that crabgrass may start germinating when the soil warms up to 60 degrees, but it can continue to germinate over the next 12 weeks. If you apply your preventer material too early, it may dissipate before all the crabgrass germinates later in the summer.

Forsythia is also an indicator that it’s time to prune your roses. Local Tri-City Rosarians recommend pruning your roses when Forsythia is in bloom. Now is the time. As you prune, you may find that last December’s severe cold spell caused some injury to your roses. Prune canes back to where you find white centers. Remove portions of canes where the centers are brown, tan or beige.

It’s warming up fast, so if you haven’t planted your early cool season crops, you’d better get going. Gardeners often like to plant their peas on St. Patrick’s Day. Peas will germinate as soon as the daytime temperature reaches 45 degrees, but grow best when temperatures are between 50 and 60 degrees. If you haven’t planted your peas, lettuce, and cool season spinach, you should. Also, get ready to plant your broccoli, cabbage, cauliflower, carrots and beets soon.

Now is also the time to cut back your ornamental grasses that have died back to the ground over the winter. Cut the grasses back to about 4 to 6 inches from the ground. Some of the cool season grasses have already started to grow, so be careful not to cut back into new green growth. Start by tying all the stems in the clump together using rope or a bungee cord. Use a hedge trimmer or small chain saw to cut across a clump of tough- stemmed grasses. Soft or fine stemmed grasses can be cut with a serrated knife or hand sickle. Clean up evergreen grasses, by gently combing the grass with your fingers using a gloved hand.

So for now it’s go, go, go, unless it snows.

Published: 3/13/2010 11:23 AM

A ROSE IS A ROSE, INCLUDING LANDSCAPE ROSES

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

Just like the tomato is the staple crop of the home veggie garden, the rose has been the universally favored flower of the garden. I know many gardeners who have ten rose bushes or more. However, I’ve noticed that fewer gardeners today are indulging in their passion for roses on a large scale. The reasons? Modern hybrid teas and floribunda shrubs are a lot of work, requiring regular pruning, deadheading, and pest control. Also, with the emerging trend of smaller yards, gardeners don’t have the room to overindulge in their love of roses.

To meet the changing needs of gardeners, rose breeders have worked at developing roses that are more compact and have good repeat bloom. They’ve also endeavored to create roses that are hardy, don’t sucker, are resistant to disease and insects. Many of the new roses that meet these criteria are placed in the general category of “shrub roses.”

However, the “shrub rose” category is a bit murky and seems to be a catch-all term for roses that don’t fit in anywhere else in the traditional categories, such as hybrid teas, floribunda, climbers, or miniatures. A rose classified as a “shrub rose” may be compact and easy to fit into a garden with other plants or it may be as tall as six feet or more. In retail catalogs, some growers have decided to aptly name the improved modern shrub roses, “landscape roses.”

Meidiland Landscape Roses, developed by French breeders, were perhaps the first of the newer shrub roses to catch the fancy of American gardeners with 1987 All America Rose Selection (AARS) winner, Bonica. It’s a vigorous shrub rose growing to five feet tall and wide with clusters of single soft pink flowers. Members of the Meidiland Landscape Rose family are known for their easy maintenance and abundant bloom.

The Knockout series of landscape roses, developed by Bill Radler is a well known line of modern landscape roses. In 2000, Radler introduced the first of the series, ‘Knockout,’ another AARS winner. Now called a “classic,” ‘Knockout’ was the first in this illustrious series. It filled the criteria for the modern shrub roses with compact growth (height and width of 3-4 feet), great hardiness, disease resistance, and even drought tolerance.

The Carefree series is another popular named series of roses launched in 1991 with

Carefree Wonder

. It has semi-double hot pink and white flowers and grows five feet in height. This year ‘Carefree Spirit,’ with single bright red flowers is a 2009 AARS winner.

Pruning and deadheading are two of the most onerous tasks of modern hybrid roses, but the attractive feature of many of the landscape roses is that they don’t require as much detailed pruning. All that’s needed are hedge shears to prune shrubs back to half their height in late winter. For those who feel they must, the shrubs will also benefit from pruning out some of the oldest canes and any dead or weak growth . Deadheading is easy, especially since many landscape roses are self-cleaning, not requiring pruning to remove spent blooms to prompt re-bloom. If they’re not self-cleaning varieties, all that’s needed is hedge shears to shear off the spent blooms.

If you love roses, but don’t want all the hard work that can come with growing them, consider planting a few of the new landscape roses. After all, a rose is a rose, these are just easier to grow.

Published: 11/21/2009 12:49 PM

BEAUTIFUL MAGNOLIAS

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

When homeowners want to plant a small spring flowering tree in their yard, their thoughts tend to gravitate towards flowering dogwood, plum or cherry trees. These are quite pretty trees, but in my opinion the hybrid magnolias are even more worthy of their attention.

On the top of my list are the Loebner magnolias. It’s likely you haven’t heard a lot about them, but they are an awesome, extremely beautiful spring flowering tree. I tend to gravitate towards trees with fall color over trees with spring flowers, but the Loebner magnolias are an exception. They are a cross between Magnolia kobus (Kobus magnolia) and Magnolia stellata (star magnolia).

With one parent being shrubby in habit, these hybrids typically top out at a height of 20 to 30 feet and a width of 20 to 35 feet, a respectfully small tree for home landscapes. The large fragrant flowers open in early spring. Their flower color varies from rosy pink to white depending on the cultivar.

The leaves are deciduous and from three to five inches in length. Their yellow-brown fall color is unremarkable. As this small tree matures, the light gray bark and low, dense branching structure give the tree an attractive sculptural habit. The tree has a moderate rate of growth, forming a rounded to broadly rounded crown when it matures. It’s hardy to USDA Zone 5.

My favorite cultivar of the Loebner magnolias is

Leonard Messel

, a not so pretty name for a gorgeous tree. This was a chance hybrid raised by Colonel Messel in Sussex England. The outside of the blooms are fuchsia to magenta and the inside of the flowers are pinkish white. Renowned woody plant expert Dr. Michael Dirr, says that ‘Leonard Messel’ is “truly one of the great magnolias, lovely fragrance, cannot resist picking a flower and savoring the fragrance.” A chance seedling from ‘Leonard Messel’ with deeper flower color is called ‘Raspberry Fun’

Another common Loebner cultivar is ‘Merrill

. It’s a vigorous grower with a somewhat more upright habit. It’s a profuse bloomer with fragrant large white flowers with a hint of pink produced in early spring. Other white-flowered cultivars include ‘Ballerina’ with pure white flowers that are similar to those of the star magnolia and ‘Spring Snow’ with creamy white flowers with a rounded outline that are produced a little later than the other Loebner magnolias.

While these magnolias would prefer a slightly acid soil, they seem to tolerate neutral to slightly alkaline soils without any trouble. They will flower best when planted in full sun, but will tolerate partial shade. Protection from the wind is advised. They do best in a well drained soil that is kept moderately moist and not excessively wet or extremely dry. Mulch with several inches of bark to keep the shallow roots cool and protected.

If you have never seen one of these magnolias, plan a trip this weekend to the Master Gardener Demonstration Garden in Kennewick (1620 S. Union behind the Mid-Columbia Library.) You’ll see a beautiful

Leonard Messel

near the Japanese Garden. On your visit you’ll also appreciate the many pretty spring flowers in bloom.

I’m planning to plant a

Leonard Messel

in my backyard as soon a I can find one!

Published: 4/11/2009 2:34 PM

ATTRACTING BUTTERFLIES

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

“Build it and they will come.” I know you’ve heard that quote from the movie “Field of Dreams” applied to a variety of situations and I’m shameless enough to use (or misuse) it too. However, I’m going to modify it to “plant it and they will come.” If you plant the right plants, you can attract butterflies to your yard and garden.

The butterfly bush is one plant that is truly a butterfly magnet. The butterfly bush attracts various butterflies with its many spikes of purple to pink flowers. This shrub is not a particularly neat plant and perhaps not well suited to smaller landscapes and gardens. Buddleia davidii is the most common species of butterfly bush grown by local gardeners. It grows into a large arching, somewhat rangy shrub, 5 to 10 feet tall. During our milder winters it survives intact, but during more severe winters like this past winter, they usually die all the way back to the ground. Even if the winter doesn’t take them back to the ground, many gardeners prune them back to just above ground level to maintain their shrubs at a smaller, more manageable size. This doesn’t cause a problem since the flowers form on the new wood that grows each spring.

Buddleia davidii is easy to transplant and grow. It thrives in well-drained soils, but will also grow in alkaline soils and other rather tough or polluted situations. Butterfly bush needs full sun for the best growth and flowering. Buddleia davidii has purple-lilac colored flowers, but there are also various named cultivars of it with deep pink, mauve, lilac, blue, reddish-purple, or deep purple flowers. It has few pest problems with mites and earwigs sometimes causing minor trouble.

While Buddleia davidii is the most common form of butterfly bush, there are over 100 species and cultivars in the Buddleia genus. Some species bloom earlier in the season on the previous year’s wood, such as Buddleia alternifolia, B. asiatica, B. colvilei and B. globosa. They’re pruned when flowering is over in the middle of summer, not in late fall or early spring. Prune these types to maintain shape and remove the oldest wood. Blooming earlier in the season, these species provide for butterflies that also make an early summer appearance.

The different species are a bit different than Buddleia davidii. B. alternifolia has small lilac color flowers on drooping branches with willow-like leaves and grows to 12 to 15 feet tall.

B. asiatica has white flowers and big and grows to 15 feet. B. colvilei has big, tubular, dark pink flowers and grows to 15 feet tall. B. globosa has round clusters, instead of spikes, of orange flowers. The leaves are big and leathery and the plant grows from 10 to 15 feet tall.

There are also other species and numerous Buddleia hybrids being offered by the nursery trade. Buddlleia davidii and many of the Buddleia species are native to China, but B. globosa is native to Chile. Horticulturists and plant breeders are still seeking out new species and trying to develop new cultivars and hybrids. I recently purchased a yellow-flowered butterfly bush to serve as a companion to my Buddlleia davidii cultivar ‘Harlequin’ which has variegated leaves with a creamy white edge and red-purple flowers. By the way… I thought my ’Harlequin’ was dead this spring and was prepared to dig it out. My patience (or procrastination) was rewarded when it started to sprout at the base and grow new shoots in late spring.

As much as many gardeners appreciate the ability of Buddleia davidii to attract butterflies and bees there is concern that it’s become a weed problem and it has even been declared a noxious weed in Oregon. Tim Butler, supervisor of the Oregon Department of Agriculture’s Noxious Weed Program, notes that this popular ornamental “has extreme invasive qualities. Like other noxious weeds, it is very competitive with native plants .” Buddleia davidii has been placed on Oregon’s “B” list of noxious weeds. Washington’s Noxious Weed Board is also considering declaring butterfly bush a noxious weed because it has become invasive, displacing native plants in a variety of natural areas such as coastal forests, roadsides, abandoned railroads, streams and river banks.

Butterfly bush is a tough plant that can even get started in the cracks between sidewalks. The many little flowers produce an abundance of seeds that seem to find their way about on the wind. Many local gardeners have not noted that their buddleias are invasive, but the bushes located in the Bird and Butterfly Garden in the Master Gardener Demonstration garden located in Kennewick, have been know to sow their seed in nearby parts of the garden. While many gardeners still want to include this plant in their gardens to attract butterflies, we should take care not to let them become weedy. This can be accomplished by removing the fading flowers as they fade and before they shed their seed and by destroying “volunteers” that come up from seed.

There are also other less invasive garden plants that we can use to attract butterflies. Some of these are daylily, petunias, lavender, phlox, aster, cosmos, zinnia, yarrow, lilac, thyme, ornamental milkweed, and liatris.

Published: 7/10/2004 2:20 PM

PRUNING FLOWERING SHRUBS

written by Marianne C. Ophardt WSU Extension Faculty for the Tri-City Herald, Kennewick, WA About this time of year, gardeners become pretty anxious to get out in the garden ad DO SOMETHING! Despite some spells of very mild weather, we must remember that it’s still winter. However, pruning is one gardening chore that gardeners can do now. Before you get ready to snip, cut, and lop, there are a few things you should ask yourself. Why are you pruning? You shouldn’t prune just for the sake of exercise. Have a reason for pruning. Is the plant too big for its space? Does it look lopsided and need a little shaping? Do you want to increase the flowers on a flowering shrub? Does it have dead or broken branches? Do you want to open up crowded growth? Does it obstruct a path or view? All are valid reasons for pruning, but before you make your first cut, find out the best way to accomplish your pruning goals. Too often gardeners, even experienced gardeners, don’t know the correct way to prune and don’t understand how plants will respond to their pruning cuts. For example, hedging or shearing of shrubs results in a profusion of twiggy growth at the ends of the branches. Done year after year, this leads to thick growth on the outside of the shrub. This thick growth shades the inside of the plant, eventually causing thin, sparse growth at the base and inside the shrub. On flowering shrubs, shearing reduces blooming. Today let’s talk about pruning shrubs. The best way to prune most multi-stemmed flowering and non-flowering deciduous shrubs, is by renewal pruning with thinning cuts. This involves removing one third of the oldest stems down to the base. The thickest and barest branches should be removed first. This opens up the inside of the shrub up to light and gives the younger stems space to grow. Stems that are not removed can be trimmed with selective thinning cuts to maintain a desirable shape and size. Multiple-stemmed shrubs that are candidates for renewal pruning include lilac, forysythia, kerria, deutzia, kolkwitzia, lilac, spring-flowering spirea, mockorange, and weigela. I like to prune these in late winter when the leaves aren’t present. It makes seeing and finding what needs pruning much easier. However, many gardeners prefer delaying pruning until after flowering, so they don’t lose any flowers in the spring. While some references indicate a need for annual renewal pruning on multi-stemmed shrubs, the slower growing shrubs need it less frequently and some don’t need regular pruning at all. Plants that need only periodic pruning to correct shape or remove injured wood include cotoneaster, winged euonymus (also known as burning bush), flowering quince, deciduous barberry, magnolia, photinia, potentilla, sumac, viburnum, and witch hazel. Pruning multiple-stemmed shrubs that flower from mid to late summer on the current year’s wood are pruned differently. A general rule is to cut all the canes or stems of these shrubs back to near the soil line in early spring. This includes butterfly bush, Rose-of-Sharon, callicarpa, caryotperis, perovskia (Russian sage), and summer-flowering spirea. Of course, after severe winter cold, some of these die back to the soil line and this easily dictates where pruning should occur. Of course not all shrubs are multi-stemmed. Some are pruned and trained when young to resemble small shrubby trees with only one or a few trunks. Other shrubs grow that way naturally. Their branches should not be pruned back to the base. Instead, selective thinning cuts are used to thin crowded growth if needed. Several times I’ve mentioned ‘thinning.’. Thinning cuts are ones that remove an entire branch or stem back to it’s origin. In many cases this is back to a larger branch or trunk, and with multiple-stemmed shrubs it’s back to the ground. When a thinning cut is made there is no stub or portion of the branch left. Heading cuts are in contrast to thinning cuts. Parts of branches removed with heading cuts are removed by pruning back close to a healthy bud on the stem, reducing the length of the branch. Heading cuts are made to an outward facing bud. This directs the new growth outwards, rather than inwards towards the center of the plant. Finally, before you get started pruning, make sure your tools are nice and sharp. Whether it’s hand pruners, loppers, or pruning saws, the job will be easier if the blades are sharp. It also causes less injury to your shrub or tree. Hand bypass pruning shears with scissor type blades are great for cutting wood up to about three-quarters inch in diameter. If you lack hand strength or have weak wrists, look for ratchet pruners that use a ratchet action to give you more leverage. Most ratchet pruners have anvil type blades that don’t make as clean a cut as do bypass pruners. If you need to cut larger branches that are over three-quarters inch in diameter, you’ll need a pair of loppers. Again the bypass types will give you the cleanest cut. Ratchet loppers compensate for gardeners with weaker upper body strength. If you really have some big pruning jobs to do on wood larger than 1.5 inches in diameter, invest in a quality pruning saw. Good tools will make the job of pruning easier. Pruning Note: Roses are inarguably the most popular multi-stemmed flowering shrubs… but they should not be pruned now. The Tri-City Rosarians recommend waiting until forsythia (the yellow flowered shrub) blooms, even if their buds are starting to swell now.

Published: 1/29/2005 2:00 PM

HYDRANGEAS WORTH A TRY

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
It’s nice to see a resurgent interest in flowering shrubs. The flowering shrubs in our grandmothers’ gardens were often pretty only for the short time that they were in bloom. The rest of the growing season, at best they provided a backdrop for flowers planted in front of them and at worst they were big, ugly and ungainly.

In recent years, plant breeders have been developing new flowering shrubs that are better behaved and that provide multi-seasonal interest. Last week I talked about big leaf hydrangeas… a plant generally not considered well suited to our hot summers and sometimes severely cold winters. However, gardeners have some viable options with different types of hydrangeas. Plant breeders have been tinkering with these other hydrangeas to develop plants that meet the differing needs of gardeners across the country.

Hardy hydrangeas (Hydrangea paniculata), also known as panicled hydrangeas, is one of these other types getting attention from plant breeders. These hydrangeas are very winter hardy and have a conical or plume-like flower head that are different than the flat-topped lace-cap or mophead clusters of the big leaf hydrangea. In cold climates the hardy hydrangeas are able to bloom reliably because they form their buds in the early summer right before they bloom in mid-summer.

Our grandmothers grew the standard hardy hydrangea cultivar ‘Grandiflora’ known as Pee Gee. The large flowers of Pee Gee were noteworthy, but the stems weren’t strong enough to support them. Newer cultivars stand on their own, supporting their big flowers without collapsing or bending over. One of these is ‘Limelight.’ The six to twelve inch flower heads are at first a bright green and later turn to white, pink, and then deep pink in the fall. ‘Limelight’ is a bit tougher than the bigleaf hydrangeas and is able to perform better in sun and heat. However, in our region it’s a good idea to protect it from mid-afternoon sun. A mature height of eight to twelve feet is pretty big for many yards, but it can be kept to a shorter height with pruning.

‘Pinky Winky’ is another new hardy hydrangea with exceedingly large two-toned pink and white flower heads. Blooming from mid-summer to fall, the gargantuan 12 to 16 inch long flower heads are held upright on strong stems. This hydrangea isn’t as fussy as most hydrangeas, adapting to different soil types plus they’re somewhat tolerant of drought. The shrub grows to a height of six to eight feet.

‘Little Lamb’ is a smaller version of panicled hydrangea. It only grows to a height of three to four feet and has smaller white flower heads produced from mid-summer to fall. In fall the blooms turn pink. Easy to grow, this is a hydrangea that gardeners with small yards should try.
Another new hydrangea is ‘Quickfire.’ It dependably produces blooms from early summer into fall. The flowers start out white and turn to pinkish red.

Many gardeners aren’t familiar with the climbing hydrangea (Hydrangea anomal subsp. petiolaris). It’s a native to Japan and the coast of China. The showy six to ten inch diameter flower heads are airy lacecaps. The vine climbs by aerial tendrils and has glossy heart-shaped leaves along with exfoliating brown bark. Renowned and opinionated woody plant expert Dr. Michael Dirr favors it with praise as the ‘best vine.’

Climbing hydrangea is not overly vigorous when young and it’ slow to establish. After several years it will pick up the pace and eventually grow to 50 to 80 feet tall. Since it climbs with aerial rootlets it needs a rough surface to climb on, such as brick and stone walls or tall tree trunks. Two newer climbing hydrangeas are ‘’Skyland’s Giant’, a large flowered selection and ‘Firefly’ with variegated leaves. Climbing hydrangea does best in a well-drained organic soils mulched with an organic mulch.

So if you are a gardener that loves hydrangeas and haven’t been able to successfully grow the bigleaf type, you might find your luck will change if you try one of the hardy hydrangeas.

Published: 11/17/2006 2:28 PM

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