Washington State University Extension

Garden Tips

Pruning RSS feed


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written November 8, 2015

Two weeks ago we talked about the fall garden chores that should be done once fall arrives and cool weather starts to prevail. Here are some tasks that are “good-to-do” but are not absolutely necessary.

CLEAN UP VEGETABLE GARDEN: In the fall, it is a good practice for vegetable gardeners to clean up the garden by removing plants that are done producing or killed by frost. Plants without any obvious disease problems may be chopped up and composted. However if the plants were diseased, do not use them in a compost pile. Once you have the plants removed, add organic matter to the soil by tilling in finished compost or chopped up leaves.

PRUNING BACK ROSES? If you originally come from a colder area of the country like I do, you are probably familiar with the process of severely cutting back roses in the fall and covering the bushes with soil or a loose mulch for protection from cold temperatures. Because winter temperatures here are usually not bitterly cold, severe fall pruning is not needed and can actually make the plants more vulnerable to cold temperature damage. However, after several hard frosts it is good to prune tall rose shrubs back to a height of about three feet to keep them from blowing about in gusty fall and winter winds and possibly uprooting the plants.

CLEAN-UP FLOWER PLANTERS: Spring is a busy time of year so the more cleanup you do now, the further you will be ahead of the game next season. Take advantage of mild fall days to tidy your flower container gardens. Remove all the plants, roots and all, by pulling or digging. Use a garden knife or a sharp trowel to dig and break up root masses and clumps of potting mix. (If you grew ornamental sweet potatoes, you may find a sizable tuber or “sweet potato” as part of the roots. These are edible, but are most likely not very tasty.)

GARDEN TOOLS: If you put your tools away clean and in good working condition, they will be ready for you next spring when you are anxious to get out and GARDEN! Use a wire brush to clean the soil off your digging tools and then use a flat mill file to sharpen their blades, if needed. Do this by filing away from you using long strokes. If you have not done this before, you can probably find a “how-to” video on-line. For tools with wooden handles, rub the wood with boiled linseed oil. This helps prevent the wood from drying and cracking. If the handle is rough, sand it before applying the oil.

YARD ART: If you have any pottery or concrete bird baths, take time to clean them off and store them in the garage or storage shed. If you leave them out in the yard, any water in them may freeze, causing cracks and chips. I winterize my bird bath by scrubbing out the bowl, wiping it off, and then placing it under the eaves (no room in the garage) with the basin upside down so it will not collect leaves, snow, or rain. If you have a bird bath or fountain that is too heavy to move, drain it, fill the bowl with burlap or blankets to absorb condensation, and then cover it with heavy plastic sheeting to prevent it from filling with moisture. Secure the plastic well to avoid problems with wind. If removable, take fountain pumps indoors for the winter. Also, clean off other types of garden art, like gazing balls and wind chimes, and store them away in the garage.


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


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


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published April 11, 2014


Last weekend I took on the project of pruning my roses, nicknaming myself “Marianne the Merciless.” I showed no mercy to my roses that had not been pruned correctly for several years because I had negligently waited too each spring to get in there and get the job done right.

I pulled on my rose gauntlet gloves, picked up my sharpened loppers and hand pruners, and went to work. It was not an easy task. Roses grow terrifically well in our region and mine had grown to a height of almost six feet last year. When I was done, I had mountains of rose prunings and bushes that hopefully will perform better this summer.

Satisfied with a job well done, I was amazed that I did not look like I had tangled with a vicious animal. I wore long sleeves and my new rose gauntlet gloves. The glove hands are made of leather and the “gauntlet” cuffs are made of canvas that reaches almost to my elbows. They kept my hands and arms free of thorny pokes and scratches.

I purchased my pair at a local garden store, but they can also be ordered on-line. If you have a lot or roses or raspberries, you should consider investing in a pair of all-leather rose gauntlet gloves. My new gloves were quite stiff when I started and a little tight. If you purchase a quality pair of gauntlet gloves, make sure they are the right size for your hands. Many of the companies selling quality rose gloves have size charts to guide you.

The other thing that made my job easier was having sharp pruning tools. It is difficult to cut out thick woody old canes with dull loppers. If you know how to sharpen your tools, do it before taking on your spring pruning chores. If not, find someone who can do it for you.

Rich Redekopp, one of our Master Gardener rose experts, told me about another “pruning” tool that I’m considering getting for taking out tough old dead wood or very thick canes. Redekopp recommends the cordless Milwaukee Hackzall Reciprocating Saw fitted with a pruning blade. He pruned some roses outside our office and his saw made quick work of the gnarly old dead growth in these neglected roses.

Roses are very forgiving. You can prune them incorrectly (or not at all) and they will still produce beautiful blooms. However, with correct pruning your shrubs will not grow out of control and the rose blooms will be bigger. Helen Newman, Master Gardener rose expert and Tri-Cities Rosarian, notes that your goals are to remove the “dead, diseased, damaged, and dinky” canes. Experts call them the four “D’s” of pruning roses. You should also remove shoots that are old and gnarled, growing in the center of the shrubs, or crisscrossing each other.

Published: 4/11/2014 11:46 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
Published 4/19/2013

I have restrained myself for a while, but after a visit this past week to one of our local shopping centers, I just can’t stop myself from saying something. Have you seen the awful way that trees are pruned in many local shopping centers and commercial landscapes?

It saddens and angers me when I see parking lot trees that have been mangled with a chainsaw. The mutilation involves chopping back the tops of these young trees. They end up looking more like ugly hat racks rather than beautiful trees. All I can do is wonder why this keeps happening?

Chopping back or ‘topping’ the top of a tree is never recommended, whether a tree is large or small. The stumps of the hacked off limbs will not be able to close over, allowing wood decay fungi to infect the tree. In addition, this radical loss of branches weakens the tree by taking away it’s ability to make carbohydrates, the food it needs for growth. This makes the tree more vulnerable to attack by insects and diseases. It drastically shortens a tree’s effective life. Why did the business even bother to plant the trees? My guess is that they don’t care about trees, but were obligated to plant trees as part of their building plan.

Businesses may have several different rationales for mangling their own trees. One reason is that they want potential customers to see their signs and their building. This is a poor decision for three major reasons. First, while concern over the blockage of signs is valid, the problems could have been avoided before the trees were planted with good planning involving the proper selection and siting of the trees. Later, as trees grow strategic pruning can both maintain their beauty and allow for good views of a business and its signs.

Secondly, when you top a tree, the regrowth will be very twiggy and dense, making it even harder to see a sign or a business. Topping is considered high maintenance pruning because once topped, tree it will need pruning again (and again) every few years. This further weakens the tree and places it on a quicker path of decline.

Yet another reason that topping these trees is ill advised for businesses is the impact it can have on their bottom line. Research indicates that shoppers and patrons respond positively to landscapes with healthy and well-maintained trees. The quality of the landscape reflects on the perception of the quality of goods and services a customer will receive.

Surveys indicate that customers are willing to pay from 7 to 20 per cent more for goods and services from a nicely landscaped business with healthy trees. Good businesses pay close attention to the appearance of both the inside and outside of their buildings. They should be just as mindful of the impression that their landscapes and trees give to customers.

Finally, one very bad reason that businesses have their trees topped or badly pruned is that they don’t know any better. They may ask whatever landscape maintenance company that cuts their lawn and weeds their landscape to cut back the trees for them. They need to become better informed. What they should do is hire a well qualified ISA (International Society of Arboriculture) certified arborist to thin the trees or reduce the size of the crowns. If the arborist can not prune the tree to a satisfactory size, then the business owner should consider removing the tree and planting the right tree in a more desirable location.

I have been spreading the message of ‘Do Not Top Trees’ for years. I wish more people would listen.

Side Bar: April is when communities around the country celebrate Arbor Day. The day was first started 1874 by J. Sterling Morton in Nebraska City, Nebraska. It became a legal holiday in Nebraska in 1885 and has since spread around the country and even many parts of the world. Morton is quoted as saying ‘The cultivation of trees is the cultivation of the good, the beautiful, and the ennobling in man, and for one, I wish to see it become universal.’

Locally, our three cities are also celebrating Arbor Day with official ceremonies and tree plantings. You are welcome to join one or all to celebrate Arbor Day!

Kennewick: Grange Park at 9:00 a.m. on Saturday, April 20th

Pasco: Memorial Park at 10:00 a.m. on Saturday, April 20th

Richland: John Dam Plaza at 1:00 p.m. on Friday, April 26th

Published: 4/19/2013 11:22 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
Published 3/8/2013

Every time you turn around, plant breeders are coming up with new a hydrangea. In the ‘old’ days hydrangeas were beloved, but gardeners had a hard time figuring out how to prune them. That’s because different species are pruned differently. Now with the many new cultivated varieties that breeders are introducing, it’s even more confusing. Thankfully, Tim Wood at Proven Winners has made it much easier.

All you need to know is the size and color of the flowers to know which hydrangea is which species… and then you can figure out how to prune it. If your plant has big pink or blue flowers, it’s a bigleaf hydrangea (Hydrangea macrophylla). Hydrangeas with round white or pinkish flowers are smooth hydrangeas (Hydrangea arborescens). Hardy hydrangeas (Hydrangea paniculata) have white, greenish, or pink conical flowers. That makes pruning much easier… if you know what the flowers look like.

According to Wood, bigleaf hydrangeas don’t need much pruning. Prune out a few of the oldest stems down to the ground each year, removing no more than one-third of the total stems in one year. Do this right after they flower in the summer. Don’t prune these in late winter or spring. Bigleaf hydrangeas flower on older wood, so pruning before flowering removes the flower buds.

The smooth hydrangeas bloom on new wood or the wood that will develop in the coming season. These should be pruned back to a height of one to two feet in late winter. This helps encourage stronger stems that are less likely to droop over with the weight of big flower heads.

The hardy hydrangeas are pruned back to the ground or, if you want taller plants, prune back to within one to three feet from the ground.. They also bloom on new wood.

Many of the new hydrangeas on the market originally come from Spring Meadow Nursery that specializes in the propagation of ‘new and superior ornamental flowering shrubs’ and introduces them to gardeners through the Proven Winners marketing program.

To make things even more confusing Spring Meadow Nursery has developed a line of ‘reblooming’ largeleaf hydrangeas. Their line of ‘Let’s Dance’ hydrangeas bloom on both new and old wood. Right after flowering, deadhead spent flowers by cutting back to the first set of leaves beneath the flower head. After bloom, prune out any dead, thin or weak wood down to the ground.

New to the ‘Let’s Dance’ line this year is Let’s Dance Diva. Diva has a huge flower head made up of flowers with baby pink petals (actually sepals) as big as the size of your hand. Another new Spring Meadow rebloomer is Paraplu with large candy pink to hot pink mophead flowers. The individual flowers (called florets) are double, giving it a unique softer look. Paraplu supposedly holds up well in summer heat. It also has a compact habit reaching only two and half to three feet tall and wide, making a neat little hydrangea shrub.

In my landscape I have Incrediball, a Spring Meadow introduction. It’s a smooth hydrangea with gigantic white flower heads that can reach one foot in diameter. One flower looks like an entire bouquet. The round flower heads are definitely incredible. The shrub grows to 48-60 inches tall and wide.

I’m anxious to try some of the reblooming hydrangeas. How about you? Look for these and other great new hydrangeas at your favorite nursery.

Published: 3/8/2013 10:54 AM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

Most of you know I love trees and I’m zealous about pruning trees correctly. I’ve decried the topping of trees as chain saw massacres. I’ve been known to lay awake at night worrying about the fact that anybody can take a chainsaw and sentence a large shade tree to terminal ugliness and an early demise. However, I haven’t lost sleep worrying about the smaller types of trees planted in many home and commercial landscapes. That was until last week. I was driving around town and noticed that these smaller trees were also falling victims to unskilled crews with loppers, power hedgers, and chain saws.

I have to admit to being puzzled. I understand that landscape maintenance firms need to work. What I don’t understand is why someone would think pruning small trees by hedging them is a good idea. Concern for the trees, gave me the courage to go in and talk to the managers of several Tri-City businesses. It’s their prerogative to have the trees pruned any way they choose, but I really wanted to know why they had their trees pruned that way. Knowing their reasons, would help me educate the community on why it was wrong.

REASON 1: The Trees Were Growing Too Wide and Too Dense

One manager had wanted a tree that was more pyramidal and narrower in shape. The best time to address this situation is when a tree is selected. It’s important when selecting trees to pick ones that grow to the mature size and shape you want for your landscape. Just like there are different cultivated varieties (cultivars) of tomatoes, there are also different tree cultivars. There are many named cultivars of trees. When you select one at your local nursery, find out what size and shape they will grow into. For example, one red maple (Acer rubrum), ‘October Glory,’ grows to 40 feet tall with a broadly oval to round crown when mature. The ‘Scarlet Sentinel,’ also a red maple, grows to 40 feet tall, but it has an upright and narrow crown when mature with a strong upright branching pattern, making it especially good for along streets and parking lots. They’re both red maples, but they grow into two very different forms.

REASON 2: The Tree Wasn’t the Desired Shape.

Again, this could be avoided with proper tree selection and knowing how a certain cultivar will perform once its mature. Trees are often somewhat pyramidal when young and develop a more oval to rounded shape with age. You should not “hedge” or “round off” the tree to get a desired rounded or oval shape. This type of pruning is called “tipping.” Tipping is similar to topping, but not as severe in appearance since only the smaller branches around the surface of the canopy are involved.

Tipping is bad because it upsets the natural growth pattern of the tree. Branches are cut off mid-branch, irrespective of the location of side branches or buds. This results in the development of numerous weakly attached sprouts near each cut. These sprouts will be prone to breakage from wind as they grow larger. It also makes the branch and the entire tree vulnerable to attack by insects and disease and can lead to the eventual death of that limb and the tree.

If the tree had been shaped using thinning cuts, the natural balance would have been maintained and the resulting growth would be more restrained. With thinning cuts branches are pruned back to branches at least one-third the diameter of the branch being removed. The entire branch is removed and heading cuts in the middle of the branch are not used. Thinning cuts are also the best way to reduce tree size and density, the first reason cited for tipping.


Once hedging or tipping is done to a tree, an owner is locked into repeating the process year after year. This creates a hedged tree whose canopy of leaves develops mostly at the ends of the branches and shades out the inner limbs. Because the canopy is reduced, the production of carbohydrates is also reduced. This results in slower root growth and stresses the tree. As a result, it is less able to tolerate drought, heat, and attack by insects and disease. The life of the tree is shortened. Once a tree has been hedged, a trained arborist can come in and correct the structure. However, it requires several detailed prunings over a span of years to correct a tree’s structure. This takes time and money.

So help me get the word out. Tipping is just as bad as topping. Don’t shape trees by hedging or tipping them. Use thinning cuts to shape and reduce the size of a tree. Better, yet research the trees you’re planting so you won’t have to prune to keep the tree’s size restricted or try to change its shape.

Published: 3/14/2009 3:04 PM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

I often get asked a wide variety of questions related to horticulture. It’s part of what makes my job so much fun. I’m a person who doesn’t like to “shoot from the hip” so when I don’t know the answer to a question, I take the time to do a little research. I’d prefer to give a correct answer so both the inquisitor and I can learn something. Here are four questions that I received in recent weeks…. with answers that I needed to look into.

QUESTION 1: Who is correct, the British or the Americans when it comes to referring to sweet corn as “corn” or “maize”? The British apparently use “maize” to refer to what we call “corn”.

The name “corn” is an old Anglo-Saxon word used as a general term to refer to any kind of cereal grain, but sometimes has been used to refer to wheat. In Australia, the use of “corn” is restricted primarily to sweet corn. In England “maize” is used to refer to sweet corn. In most other English speaking countries “corn” is not used as a general term to refer to what we call sweet corn, pop corn, or field corn. The word “maize” is used as a general term to refer to them. “Maize” is a native American word that is used more universally to refer to what we know in this country as corn.

This points out the difficulty in using common names to refer to any type of plant from country to country or region to region. What means “corn” in one place means something else in another place. The scientific name of corn is Zea mays L. ssp. mays. There are a number of important agricultural groupings of Zea mays L. subsp. mays including the Saccharata Group (sweet corn), the Everta Group (popcorn), the Indentata Group (dent corn), the Indurata Group (flint corn), and the Amlacea Group (flour corn).

Maize or “corn” is a native American plant. Scientists believe that primitive forms of maize first grew only in the Andes region of Peru. These forms mutated and crossed with other close relatives before and after the Peruvians transported it to Central America. By way of the Central American natives, these new types of maize found their way into what we now identify as the southwestern United States and then to northern and eastern parts of the country.

Maize eventually became a common crop of most Native American tribes. While the sugary characteristic of maize probably arose through mutation a number of times, it was not favored by most tribes. It wasn’t until the arrival of the Europeans in North America that sweet corn became desirable.

Which is right, corn or maize? I’m not sure, but some U.S. gardeners are starting to switch to the term of maize when talking about what the rest of us call corn. It’s less confusing when communicating with gardeners around the world.

QUESTION 2: What is crocosmia? My friend said I should put it in my flower garden.

Crocosmia is a member of the iris family and is native to South Africa. It’s also known by its common name of monbretia. There are different species and cultivars, some with small flowers and others with large flowers produced in multiple spikes from mid summer to autumn. Flower colors range from yellow to orange to red. The leaves are grass-like and similar to those on flowering iris.

These easy-to-grow plants do best in a well drained soil and are very drought tolerant. They require little fertilizer and do well in sunny sites, but might benefit from some shade with our hot summer conditions. Crocosmia flowers open a few each day, from the bottom of the flower stalks to the tip and are excellent as cut flowers.

Crocosmia are perennials and are hardy in USDA Zones 6 to 7. A mulch should be applied for protection from the cold in late fall, especially the first year after planting, In colder areas, they’re only considered semi-hardy and are grown in containers. Croscosmia arise from corms and tend to be fast establishing and multiplying. Some of the older cultivars such as ‘Lucifer’have been known to become too crowded within a year of planting and fail to flower the second year due to overcrowding.

Cultivars include ‘Meteor’ with small yellow flowers tinged with orange; ‘Red King’ small red flowers with orange-yellow centers;

Emily McKenzie

with large orange flowers; ‘Lucifer’ with large tomato red flowers; ‘Jenny Bloom’ a hybrid with orange buds that open into golden-yellow flowers; ‘Solfaterre’ a hybrid with chocolate brown leaves and apricot yellow flowers that is slower to multiply than other cultivars; and ‘Star of the East’ a hybrid with large bright orange flowers with starry centers of cream and maroon. This plant spreads more slowly than older cultivars.

QUESTION 3: When should I prune my hibiscus?

Do you have a rose-of-Sharon shrub or hardy hibiscus? Rose-of- Sharon (Hibiscus syriacus), a hardy shrub, is pruned in late winter or early spring before new growth begins. Prune out spindly canes and one-third of the oldest growth. The rose-of-Sharon blooms in the summer on new wood.

Hardy hibiscus (Hibiscus moscheutos) usually die back to the ground in the winter and are treated like a flowering perennial. After the tops die back in late fall or winter, trim the plant back to about twelve to eight inches above the ground. When new growth begins in the spring, you can encourage branching by pinching the stems back early in the growing season. While the rose-of-Sharon is a tall shrub, growing from six to eight feet tall, the various cultivars of the hardy hibiscus range in size from two to eight feet tall and two to six feet wide.

QUESTION 4: Is there something wrong with my sycamore tree? Lots of big pieces of bark came off of the trunk and main branches early in the summer. What’s up?

It’s natural for trees to shed bark as they grow, but usually the amount is very small and goes unnoticed. However, certain types of trees such as sycamore, London plane, and silver maple slough off their bark in larger pieces. Some years this shedding is particularly heavy and causes concern… and extra work cleaning it up. There is no need to worry if the bark only uncovers more bark beneath and not bare wood. With sycamore, the patch of bark underlying the shed portion is bright to olive green that later turns to a normal gray color.

Published: 12/25/2004 2:09 PM


written by Marianne C. Ophardt WSU Extension Faculty for the Tri-City Herald, Kennewick, WA Well spring is right around the corner and anxious gardeners are trying to take advantage of the nice days to get some early spring gardening tasks checked off their “to do” lists. Number one on many gardeners

lists is pruning. This is a good time of year to prune fruit trees and ornamental trees and shrubs in the yard. The lack of leaves makes it easier to see what you

re doing, plus you don

t have a bunch of leaves to haul away or chop up for the compost. Once out in the yard, it doesn

t take long to notice that the severe cold temperatures in early January did not treat some broadleaf evergreen shrubs, such as English laurel, holly, euonymus, and photinia, very kindly. These evergreens and semi-evergreens have come through the milder winters of the past few years with little damage, but this year is a different story. Brown leaves are evident on many of these broadleaf evergreens, especially those in more exposed situations or with sunny southwest exposures. Right now, many of these plants are looking like “goners”, but don

t be too quick to pronounce them dead and start pruning severely to remove all the ugly brown leaves. It

s best to check to see if the twigs and branches are still alive. It may only be the leaves that were injured by the cold temperatures. You can check for signs of life by using a pocket knife or a fingernail to carefully scrape off the bark on twigs and branches. They

re alive if you find white or bright green tissue just beneath the bark. Dead twigs and branches will be brown underneath and may have even started to dry and shrivel. If you find dead tissue, keep checking further down on the twig, then branch, then trunk… until you find live tissue. Older wood tends to be less susceptible to cold temperature damage than younger woody tissue. If there is any doubt whether the wood is dead or alive, give it a chance to grow. Many plants that look pretty grim, often recover and start to grow. In late spring you

ll be able to see more easily where dead tissues end and live wood begins. Then you can prune your trees and shrubs to remove damaged tissue. Our string of mild winters came to an end this January, and the broadleaf evergreens aren

t the only landscape plants showing up with significant damage. As I already noted several weeks ago, rose bushes in many parts of our region have sustained quite a bit of cane damage. I checked my roses last week and found that they truly are in sad shape. You can tell if a rose cane is damaged if the “pith” at the center of the cane is tan or brown. Even if the outside of the cane is green, that portion of the cane is not going to make it if the pith is not white. The recommended time to prune roses coincides with the flowering of forsythia, the prominent yellow flowering shrub that blooms in early spring. This is when you lower the overall height of a rose shrub along with reducing the number of canes. You should also remove any very weak or competing canes. However, you don

t need to wait for the forsythia to bloom to remove the dead wood. This can be pruned out at any time. If you have a lot of roses, you might want to start cutting out the obviously dead portions now. Other plants that have apparently taken a hit from the cold winter temperatures are pine trees. Some local residents have been noticing that the needles on their pines are brown and falling off. Most of these trees appeared healthy last summer and fall and only showed signs of a problem after early January. That leads me to suspect that the spell of severe cold temperatures was involved. This is surprising since pines are usually quite hardy. We

ll have to wait until after new growth begins to judge the extent of the injury. Given our sudden hard frost in October and the severe cold in January, I predict that the English or Persian walnuts growing in the region will once again exhibit serious dieback. Last spring, many English walnuts leafed out and then started to die back. At first, several fungus diseases were suspected to be the cause of the dieback. It was later concluded that the problem was primarily due to the sudden October freeze experienced the previous fall. This same weather situation occurred again last fall when we had a hard frost in October before most woody plants were fully prepared for cold temperatures. The same type of damage will probably be evident on the English walnuts again this year, in addition to dieback from fungi that entered dead tissues that were not pruned out last year. I

m sure we

ll be talking more about winter injury in the week to come, but that

s enough for today. Let

s talk about something else. If you have some shrubs or perennials in the landscape that you need to move, now is a good time to transplant them….while they

re still dormant. First prepare the area where you

ll be planting them. If you

re planting them in a landscape bed, till the entire bed and then work peat moss or well-rotted compost into the soil. Have your holes dug and have water ready. Dig up the plant to be moved with as much of the roots as possible. The more roots you cut and destroy, the less the chance of survival. The prepared hole should be as wide and only as deep as the root mass of the plant you

re moving. Place the plant in the prepared hole and situate it so it

s at the same depth that it was growing before. Backfill the hole and then water thoroughly to settle the soil around the roots. Shrubs and trees should be planted so the top of the root system is just below the soil line… no deeper. After watering and filling in with any additional soil needed to compensate for settling, it

s a good idea to mulch with an organic material. Getting plants transplanted this early gives them a chance to start regrowing their roots and become partially established before the leaves and warmer weather start making demands on them. Once the plants start growing, roots are needed to absorb water for the rest of the plant. The later you wait, the more stress the plant experiences and the greater the chance the plant won

t survive. I

ve also noticed that some stores are already offering packaged bare root rose shrubs for sale. While I

d rather see these arrive a little later, they should be purchased and planted now… not left in the warm store or put in the garage waiting for nicer weather. Despite what the directions might say, it

s recommended that you remove the cardboard box from around the roots and then soak the roots for about one to two hours before planting. (Don

t leave it in the water any longer.) When planting roses in our area, local rosarians suggest planting the graft or bud union (the swollen area of the stem near the base of the plant) slightly below (one to two inches) the soil. This protects the graft during our colder winters, such as the one we just experienced when temperatures dropped to well below zero. To plant a bare root rose, place a mound of soil in the center of the planting hole and place the plant on top of the mound and arrange the roots over the cone. Then carefully fill in the soil around the roots, holding the plant so the graft will end up at the right level. Gently firm the soil around the roots and then water the plant thoroughly and add more soil if needed. Check the graft level before you finish. Because our area tends to be windy in the spring, it

s also recommended that you lightly mound soil or mulch at least half way up the new plant to prevent drying of the canes, even if they

ve been coated with wax to help guard against dessication. Once the top buds begin to grow and the young shoots are about two inches in length, you can remove the mound of mulch and soil. Do this very gently, or you may knock off young shoots that have already begun to grow beneath the mulch. Keep a layer of mulch over the roots to retain soil moisture and to protect the bud union. As with other shrubs, you

ll want to keep the soil moderately moist after planting so the roots can grow.

Published: 3/6/2004 2:31 PM


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

I hate to whine, but it has been so-o-o- gray for so-o-o long, it

s a wonder we haven

t all succumbed to overwhelming glumness. While it

s fun to thumb through garden magazines and seed catalogues and plan this year

s garden, even that becomes tiresome after a while. Take heart… spring will be here soon and then the buds on our trees and shrubs will burst forth with their long awaited greenery. While you wait, consider that now is an excellent time to be pruning trees and shrubs.

Late winter is a great time to prune dormant deciduous plants because the leaves are missing and you can see their framework of branches and limbs. An added benefit when you prune at this time of year is that there are no leaves . You only have to dispose of the wood you take off, not the leaves too.

Now let

s talk about why to prune your trees. These are the only reasons that you should prune a tree . In their order of importance:
1. Most important is the removal of any dead, diseased, or damaged branches. If you fail to remove them, disease (especially wood rots) can get started in dead or damaged tissues and spread into healthy wood.
2. You should also remove branches that are a hazard or causing problems. These are branches that might obscure a clear view of oncoming traffic when exiting a driveway or parking lot; that may be damaging a structure; that threaten to decapitate whoever mows the lawn under the tree, or those that interfere with utility lines. (Keep in mind that any pruning that involves utility lines should be done by a professional arborist. Never attempt it yourself.)
3. It

s also important to prune young trees with structural problems to avoid bigger problems in the future. If there are two competing central leaders, one should be removed. If there are bad crotch or branch angles… ones less that 45 degrees from the main trunk… pruning is warranted. If you leave these bad branching angles, there is a good chance the tree will split or one of the branches may break off the tree when the tree grows and the branches get larger and heavier.
4.Least important is pruning your tree simply for aesthetics, to create the form or shape you want. However, if you purchase a young tree that is asymmetrical with many more main branches on one side than another, you should prune out branches spaced too closely together or ones rubbing against each other.

There are some reasons people prune that aren

t valid.
1. It

s an act of futility to try and keep a large tree small with pruning. Large and small trees are that way because of their genes. Their genes tell them what shape and how big and they should grow. Don

t try to fight it with pruning. It

s better to plant a small tree that won

t outgrow its space. Of course, sometimes you buy a property where large trees have already been planted. Periodic, selective pruning can be a way to temporarily reduce the size of a tree, but it will still try to grow up to its predetermined mature size. Keep in mind pruning large trees is best left to professionals who have the equipment to safely prune large trees.

2. Don

t prune the top of the tree because it

s become so big and you

re afraid it will blow over. If a tree is healthy and has a well developed root system, it should be able to withstand heavy winds. Trees that blow over in wind storms usually have very shallow root systems or compromised root systems. Shallow root systems can be due to high water tables, shallow watering, excessive watering, compacted soils, or a limited volume of soil available for development of a root system. Compromised root systems are those where trenching or other activities have severed large roots; where excessive soil moisture has resulted in root rot; or where the tree was planted with kinked and girdling roots that prevented the development of a stable root system.

In the past, arborists have recommended that a tree

s crown be “thinned” to allow for air flow and decrease wind resistance where blow-over is a legitimate concern on larger trees with questionable root systems, especially conifers. Interestingly, new research is indicating that thinning may actually increase a tree

s resistance to the wind and make it more prone to blow-over.


This is a good time of year to stand back and look at your trees, to see if they do need pruning. Most ornamental trees, large and small, don

t require regular pruning , but if your tree needs any corrective pruning… now is a good time to look for it and take action.


s also a good time of year to look at the results of past pruning cuts. The results of past topping and stub cutting is very evident. Topping and stub cuts result in lots of sprout growth that tend to grow straight up and ruin the natural shape and beauty of a tree. The sprouts come from adventitious buds and are weekly attached to the trunk. As they grow, they become bigger and heavier and more likely to break off in the wind. You should also note that stub cuts don

t “heal

over, leaving an open door for wood rot fungi to get started.

If the topping activity was in the last several years, you might also notice how rapidly these sprouts grow. Usually, the growth that results from topping is very vigorous, as the tree is still trying to grow up to its mature size. If a tree must be pruned to reduce its size, selective thinning cuts will maintain the shape of the tree and minimize rapid regrowth in contrast to a tree

s response to topping.

While you have a clear view check your trees out for other problems. Look for signs of boring insects. See if you have any broken branches, splits in the trunk, or bark injuries. Look for evidence of wood rot in the trunk … trees with substantial amounts of internal wood rot are dangerous hazards.

So while it may be too early to do many things out in the garden, it is a good time to check out your trees and do any needed pruning. Call an ISA (International Society of Arboriculture) certified arborist if the trees are larger than you can safely handle. Next time, I

ll talk about pruning shrubs. In contrast to trees, many deciduous shrubs, especially the flowering ones, need regular pruning to keep them attractive and contributing to the beauty of the landscape.

Pruning Note: Conifers, evergreens with needles and cones, should not be pruned for any reason other than to remove damaged limbs or to remove branches that create a problem.

Published: 2/21/2004 2:32 PM


Marianne C. Ophardt WSU Extension Faculty for the Tri-City Herald, Kennewick, WA Invariably I get asked to talk about how to ‘put the garden to bed’ in the fall, but no one asks me to address how to ‘wake up the garden’ in spring. Apparently, there’s no need for that. Warm temperatures and longer days do a pretty good job of that without my help. Gardeners are just itching to get out and get the gardening season started. The timing is perfect, there are a number of garden tasks that require our immediate attention… PRUNING: Flowers and leaves will be popping out any day on many of our fruit trees, shade trees, roses and shrubs. If you haven’t done your winter pruning already, now is a great time before new growth makes it difficult to see the plant’s framework. Keep in mind woody plants don’t ‘need’ to be pruned. Always prune with a legitimate purpose in mind. Good reasons to prune are to remove dead or diseased wood; to correct ill-placed growth where limbs are crowded or rubbing each other; to get rid of growth that’s posing a hazard; to correct growth defects caused by narrow branch angles or past improper pruning, or to encourage better flowering and fruiting. You should have used the winter respite to clean, oil, and sharpen your pruning tools. Do it now, if you didn’t earlier. Now is a good time to consider investing in a quality pair of bypass hand pruners and bypass loppers, and possibly a small pruning saw too. Pruners with a bypass (hook and blade) mechanism make a cleaner cut than anvil types that crush the stem, leaving damaged tissue behind On multi-stemmed flowering shrubs such as forsythia or lilac, you may find you also need a small pruning saw. On these shrubs it’s recommended that you take out 1/3 to 1/5 of the oldest wood, cutting it back to just a few inches above the soil. You should also remove any crowded spindly growth. I do this every spring on my wild and gangly forsythia. It amazes me how much wood I can take out and it still grows and grows. And yes, now is the time to prune your floribunda and tea garden roses, as well as most other types of roses. The proper way to prune varies from type to type. Before you cut, find out the proper way to prune each type. Now is also the time to ‘prune’ or trim ornamental grasses and perennials. You can use hand pruners or scissors to cut back smaller clumps of grasses, but light-duty hedge trimmers will work best for larger clumps. To make cleanup easier, use twine to tie the top growth together and then cut the grass back four to six inches above the soil. New green shoots will soon appear. Trim back dead perennial stems and flowers, if you didn’t get it done late last fall. I also cut back my perennial herbs, like sage, to keep them a bit more tidy and within the bounds of their allotted garden space. The hedge trimmers come in handy for both these jobs too. IRRIGATION: Check out your irrigation system and make sure it works as soon as you have water available. While it wasn’t a harsh winter, damage may still have occurred to sprinklers and drip lines. Before hot weather arrives, check the coverage your sprinklers are providing. You can do this by placing empty straight-sided tin cans in different areas of each zone, radiating out from the sprinkler heads. Run the system for a set amount of time. Measure and compare the amounts of water (by depth) in the cans. If there is a wide disparity, you may need to adjust your heads or get new ones that can provide a more even pattern. The folks at the irrigation supply store should be able to help you with this. Despite our winter precipitation, yard and garden soils are fairly dry right now. As soon as you have irrigation water available give trees, shrubs, gardens, and lawns a thorough watering that moistens the soil to a depth of at least a foot. LAWNS: I know you’re tempted but it’s not time to fertilize the lawn yet. Wait until the first of May for that. It is definitely time to apply crabgrass and weed ‘preventer’ chemicals to your lawn. However, this may lead to a dilemma for you because many of the ‘preventer’ products only come in combination with fertilizer. Stand-a-lone preventers are available, but you’ll have to look a little harder for them. Timing is not as crucial with products containing the chemical dithiopyr because it will provide both preemergence control, as well as some postemergence control of young crabgrass plants. However, before you buy any product, make sure that the weeds you think are crabgrass really are crabgrass. Lots of people are battling Bermuda grass and bentgrass, thinking their problem is crabgrass. If the thatch in your lawn is greater than one-half inch thick, you should consider ‘dethatching’ with thatch removal equipment. This should be done before the middle of April. It also should be done before the application of any weed ‘preventers.’ GARDEN STRUCTURES: As you go about the yard and garden, check out your garden structures for any needed repairs. Now is when it’s easiest to fix arbors and trellises… without the green growth of vines and climbing roses to obscure what might need nailing or wiring. See if any furniture or garden benches needs a new coat of paint or stain. Clean bird baths out thoroughly. Check for loose stepping stones and patio pavers and secure them.

Published: 3/25/2006 11:24 AM

« Older Posts



Garden Tips, WSU Extension, Benton County, 5600-E West Canal Drive, Kennewick, WA 99336-1387, 509-735-3551, Contact Us

WSU Extension, Franklin County, 1016 North 4th Ave, Pasco, WA 99301-3706, 509-545-3511, Contact Us
© 2018 Washington State University | Accessibility | Policies | Copyright | Log in