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Garden Tips

Archive for October 2014

SUCCESS WITH DRIP IRRIGATION IN PLANTERS

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – OCTOBER 31, 2014

SUCCESS WITH DRIP IRRIGATION IN PLANTERS

The gardening season has come to what seems like a rather abrupt end, especially after balmy sunny weather just a couple of weeks ago. Now it is time for gardeners like me to evaluate what went well this year and what did not.

My biggest success was with my numerous large annual flower containers. At the beginning of the season I was dreading hand watering these planters every evening all summer long. Plus, going on vacation meant hiring a plant sitter to keep the flowers alive.

Listening to Dr. Troy Peters, WSU Extension Irrigation Specialist, talk about dripline tubing for irrigating raised vegetable garden beds and seeing the same type of product advertised in DripWorks’ (dripworks.com) catalog as part of a deck-garden drip irrigation kit inspired me to try watering my containers with drip irrigation again.

I previously experienced failure when I tried to water the same large pots with single sprinkler- type drip emitters placed in the center of each pot. They worked for a while, but when the plants grew taller they blocked the sprinkler emitters’ spray. After this earlier failure, I continued to laboriously water my pots by hand every summer.

Learning about the dripline products made me anxious to give drip irrigation another try. Rather than buy an on-line kit, I was able to purchase most of the needed supplies from local irrigation supply companies.

Before I go any further let me tell you about “dripline” or “emitter” tubing. It is plastic tubing (1/4 or ½ inch diameter) that is manufactured with hole-like emitters at regular spacings along the line, such as 6, 9, 12, or 18 inches.

The irrigation engineers indicate that dripline with turbulent flow emitters is “self-flushing and clog resistant” if you have a good (at least 200 mesh) filtration system. The other great feature of this special tubing is that the pressure-compensating design allows it to deliver water evenly along the entire length of the tubing.

I selected brown 1/4 inch dripline with emitters spaced at 6-inch intervals. With help, I placed a circle of the dripline on top of the potting mix before I planted my flower transplants. The brown line blends in with the potting mix. We then used 1/4 inch barbed fittings and black 1/4 inch drip tubing to connect the pots to a ½ inch delivery line running along the ground at base of the pots. The ½ inch line was connected to a timer and pressure reducer off of our irrigation water.

I used trial and error to determine how often and how long to run the timer. Once I was able to figure that out, I didn’t have to constantly worry about watering my pots. However, I did check them frequently and adjust the timer for warmer weather through the summer.

The drip system worked well. We were able to go away for a vacation. I did not have the tedious task of watering every day. The flowers flourished. The plants and I were both happy.

Published: 10/30/2014 12:43 PM

CELEBRATING THE URBAN FOREST

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published -OCTOBER 24, 2014

CELEBRATING THE URBAN FOREST

This month, the Mid-Columbia Community Forestry Council (MCCFC) is celebrating their 20th anniversary with a tree planting at the Hanford Reach Interpretive Center. I am proud to say I am an original member of the council started in 1993. However, I usually receive perplexed looks when I mention the Tri-Cities’ urban or community forest. A forest in the Tri-Cities?

The term “forest” typically evokes visions of the multitude of big trees found in a natural setting like the Mount Rainier National Forest. The Miriam-Webster Dictionary defines a forest as “a thick growth of trees and bushes that covers a large area.” Urban forests are simply the combined collection of trees, planted and maintained by people, in our cities.

American Forests goes a bit further defining urban forests as “ecosystems of trees and other vegetation in and around communities that may consist of street and yard trees, vegetation within parks and along public rights of way and water systems.”

If you doubt you live in a virtual forest go to Google Maps and look at an aerial view of this area. The tree canopy created by the local cities and residents is remarkable, especially when you compare it to the tree canopy and green spaces that existed back when residents first settled in this area. Pictures on display at the Hanford Reach Interpretive Center show what a desolate area it was in the early days.

Today things are very different and for the past twenty years the MCCFC has been working to promote the planting and proper care of trees. The council’s continued vision is to heighten the awareness of the importance of urban trees; to extend technical assistance to local municipalities; and to provide leadership on community forestry issues.

You can improve our local community forest by planting trees in your yard. What type of tree? My favorite large trees (40

or taller) for this area are red oak, red maple, hybrid maple, gingko, and river birch. My favorite “smaller” trees (less than 40

tall) are littleleaf linden, European hornbeam, and flowering dogwood. For a copy of “Recommended Trees for the Tri-Cities” developed by MCCFC members and partners go to: http://ext100.wsu.edu/benton-franklin/gardening/

Autumn, after trees lose their leaves, is a good time to plant trees in many parts of the country. However, in our region fall planted trees must be watered during the fall and winter months to keep roots alive and to promote root growth. If you are not able or willing to provide this irrigation, wait until spring to plant your trees.

When selecting a tree for your yard, look for one with a single strong central leader with the main side branches well spaced along the trunk. Avoid trees with cracked, torn or damaged bark, evidence of borers, or signs of other insect or disease infestations. Before planting, inspect the roots, looking for girdling or circling roots, extremely pot-bound or dense root systems, and under-sized or inadequate root systems. If you notice any of these problems, return the tree to the nursery. For information on planting trees and shrubs go to: http://cru.cahe.wsu.edu/CEPublications/FS047E/FS047E.pdf

Published: 10/24/2014 12:14 PM

BEETLES EATING UP ELMS

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – SEPTEMBER 5, 2014

BEETLES EATING UP ELMS

Have you been wondering why so many local elm trees are looking so sick? It is because large numbers elm leaf beetles have been dining on our elms this summer. Most elm owners do not notice elm leaf beetle damage until they are done feeding for the season. An adult beetle is about 1/4 inch long, olive-green, with two dark longitudinal stripes down its back. The larvae are yellowish green with black stripes and spots.

Both the adults and larvae of elm leaf beetles feed on elm leaves. Adult beetles eat holes in the leaves and the larvae skeletonize them, leaving only the veins and the waxy top layer of the leaf behind. The leaves then turn brown. If the population is large enough, they can defoliate a large tree by the end of summer.

Some species of elm are resistant to the elm leaf beetle. However, the Siberian elm (Ulmus pumila), the predominant elm found in many area landscapes, is not resistant. Siberian elm is a fast growing, large tree that reaches a height of 50 to 70 ft.

Dr. Michael Dirr, renown tree and shrub expert, says that the Siberian elm is “one of, if not, the world’s worst trees” because it is so messy and has brittle wood. Siberian elms produce prolific amounts leaf, branch, and seed litter, plus the tree is prone to limb breakage in wind and ice storms.

Add to long list of Siberian elm’s negative traits, the defoliation caused by elm leaf beetles. Because they are such tall trees, insecticide applications to control the beetles must be performed by licensed applicators. This is a costly service but may be worth it if the tree is of high value to the owner and if attacked repeatedly.

A less costly pesticide application is an insecticide drench applied to the soil at the base of the tree. However, this must be applied in late winter or early spring (before knowing if beetles will a problem or not) to be absorbed by the roots and moved systemically to the top of the tree. This movement can take four to six weeks or more and is dependent on water being applied to the soil regularly after application.

Elm leaf beetle populations have a tendency to fluctuate from year to year. In fact, it has been a number of years since we have experienced a severe elm leaf beetle outbreak in this area. Many insect populations tend to ebb and flow because of environmental conditions, the availability of food, and natural enemies. University of California experts note that more overwintering adult elm leaf beetles tend to die if winter weather is relatively warm or wet. Just because the beetles are causing damage this year, does not mean they will be a problem next year.

At the end of summer adult elm leaf beetles look for protected places to overwinter. “Protected places” include wall voids of nearby homes. In the spring they come out of hibernation and move back outdoors. However, some get lost and find themselves indoors. Vacuuming is the best method of control along with caulking cracks and wall voids to prevent their entry into the house in late summer.

I am wondering if the elm leaf beetles will be plentiful again next year, maybe not if we have a mild winter.

Published: 9/5/2014 12:32 PM

DIGGING SUMMER BULBS

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – SEPTEMBER 26, 2014

DIGGING SUMMER BULBS

As weather cools in the fall it is time to plant spring flowering bulbs, but it is also time to dig tender summer flowering “bulbs.” This includes plants with tender bulbs, corms, and rhizomes like dahlia, canna, and gladiolus. The “bulbs” are dug after the first hard frost in the fall and stored over the winter in a place where they stay cool but not freeze.

The best time to dig is about two weeks after the plants are hit by a hard frost, giving the top of the plants a chance to die back. After waiting the two weeks, dig the bulbs, corms or rhizomes up, cut the tops of the plants down to about six inches from the ground. Carefully use a garden fork to lift them out of the ground. Take care not to injure the “bulbs.”

Shake as much soil off the bulbs as possible and then clean the remaining soil off with water from the hose. Again, be careful not to injure the bulbs. The place them in a single layer on newspaper or cardboard and allow them to protected, dry in a dry spot like your garage for a day or two.

Dahlias: Over the summer the dahlia tubers will have developed inot a cluster of tubers. These will be divided in the spring when you go to replant them. Do not cut them into separate tubers before storing them. Place the clusters in single layers in cardboard boxes or paper grocery bags. Start out with a layer of dry sawdust, peat moss, vermiculite, or wood shavings first and then cover the tubers with a generous layer of the same material. Before storing, use a permanent ink marker to write the name of the cultivar directly on several tubers in the cluster, or write it on the bag if you store clusters in individual paper bags. Store the tubers in a cool (40 to 50 degrees F) where the temperature will not go below freezing. Next year’s growth will sprout from the buds that are located at the crown at the base of the old stems.

Canna: Cannas have rhizomes. They are treated pretty much the same as dahlias for digging and storage. The clump of rhizomes can be replanted next spring or divided and replanted. New growth next year develops from buds at the base of this year’s stems.

Gladiolus: Gladioli grow from corms that resemble bulbs. These can be dug after frost kills the leaves or six to eight weeks after all the flowers have faded. These are dryed or “cured” for a longer period of about two to three weeks in a warm (80 degrees F), dry spot out of the sun. When dry enough the old shriveled corms and tiny corms (called cormels) can be easily broken away from the base of the new corms and discarded. Do not remove the protective husks around the corm. Gladiolus corms do not need to be packed in dry materials like sawdust.

Place them in mesh onion sacks or open paper bags to allow for good air movement. Store them under cold (35-40 degrees F) conditions with low humidity where they will not freeze.

This all sounds like considerable effort at a time of year when you are almost happy to see the end of the season. Do you really have to dig and store them every year? Some years dahlias and gladioli may survive if left in the ground, but it is hard to predict when how severe winter will be and replacing all your summer bulbs can be costly. If you cannot bear to lose your summer bulbs, it is best to dig and store them.

Published: 9/26/2014 12:28 PM

WHY NOT LANDSCAPE FABRIC?

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – SEPTEMBER 19, 2014

WHY NOT LANDSCAPE FABRIC?

When we moved to our new house seven years ago, I had the enjoyable task of starting our landscape from scratch. My plan included a variety of trees in the lawn and plenty of shrubs and ornamental grasses in landscape beds around the house and the perimeter of yard. Adamantly opposed to using landscape fabric or geotextiles, the beds were mulched with a four inch layer of medium size shredded bark after planting.

Admittedly, landscape fabric or geotextiles are better than the black plastic used for mulching landscape beds in the 70s and 80s. They allow for the movement of air and water, where black plastic does not. Even though they do break down with time, geotextiles covered with mulch last longer than the black plastic in the same situations.

So why am so I fervently against using landscape fabric? To make landscape fabric more aesthetically pleasing, it is often covered with a thin layer of mulch. Bark or wood chip mulches decompose with time, creating material in which weeds can grow. While rock mulches do not break down, blown in dust can create a layer of soil where weeds can grow. Plus, landscape fabric does break down with time, especially when not covered with a thick (3-4 in) layer of mulch that blocks UV radiation.

Many gardeners who have used landscape fabrics will tell you it is not a permanent solution to weed control. Weeds will invade the beds, and then the fabrics become a nightmare, especially when Bermuda grass and field bindweed (wild morning glory) are involved. The roots or rhizomes of these trailing pernicious weeds find their way into the fabric fibers, making it impossible to rogue them with pulling. If you do try to pull them out, the fabric comes with them. Arrrgh!

The best way to control weeds in landscape beds is with organic mulches. I prefer the look of shredded bark, but wood chips are just as effective and less expensive. WSU Extension Horticulturist, Dr. Linda Chalker Scott, prefers wood chips because of some of the problems that bark shredded bark can pose. She favors wood chips because of the possible contamination of bark with salt or weed seeds and because of the sharp, pointed fibers of softwood bark are not “gardener friendly.” Plus bark can resist water penetration because of the waxes they contain.

Whether you use bark or wood chips as a mulch, the layer should be 4-6 in thick. This blocks light from getting to the soil and helps maintain soil moisture. I do advise keeping mulch away from directly around the base of trees and shrubs. It retains moisture and excludes air. A thick layer of mulch touching a plant’s base can lead to collar rot causing serious damage to trees and shrubs.

Chalker-Scott points out that if you are trying to reclaim a site or an area with serious perennial weed problems consider using a 8-12 in thick layer of wood chips. She cautions you to taper down to a very shallow layer close to trees and shrubs.

Mulching with bark or wood chips is not a place-it and forget-it situation. They decompose with time, adding organic matter to the soil. Periodically you will need to add fresh mulch on top of the old, to maintain the weed controlling 4-6 in layer, being careful to keep the mulch away from the base of plants. By the way, fall is a great time to renew the bark or wood chips in your landscape.

Published: 9/19/2014 12:27 PM

WHY NOT PLANT A PEACOTUM?

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – SEPTEMBER 12, 2014

WHY NOT PLANT A PEACOTUM?

Many years ago, famous horticulturist, Luther Burbank created the ‘plumcot’ by crossing a plum with an apricot. However, his plumcot was not a commercial success because it was too soft for commercial shipping.

Today pluots are commonly found in farmers markets and grocery stores. Pluots are a complex interspecific hybrid or ‘cross’ between plums and apricots. The characteristics of the plum are dominant in the fruit. The fruit taste like sweet juicy plums without the sharp taste of skin often associated with plums. Many of the pluots currently available to growers and gardeners have been developed by private fruit breeder, Floyd Zaiger. He introduced and trademarked his first pluot in 1989.

Keep in mind that pluots and other Zaiger hybrids are not genetically modified fruit. They have been bred with controlled cross pollination, not by tinkering with the genes. This involves crossing numerous generations of hybrids to come up with a suitable cultivar (cultivated variety) for commercial and home garden markets.

As with traditional stone fruit like peaches and apricots, there are many various cultivars of pluots and plumcots available, such as Dapple Dandy, Flavor Grenade, Flavor King, Black Velvet, Honey Punch, Flavorosa, Zee Sweet, and more. Many these have been developed by Zaiger’s Inc. Genetics in California.

Zaiger’s has also developed other stone fruit hybrids that may eventually become as popular as their trademarked pluot. This includes aprium, peacotum, nectaplum, peach-plum, and pluerry. Often, the first part of the hybrid name comes from whatever fruit’s characteristics are dominant in the offspring. For example, the pluerry, a hybrid of plum and cherry, have fruit that most resemble plum. Aprium, a complex hybrid of apricot and plum, have fruit that most resemble apricot.

Perhaps most intriguing of all the Zaiger’s hybrids is the peacotum, introduced in 2007. It is a three-way hybrid of peach, apricot, and plum. The peacotoum’s flavor is described by marketers as complex and unique, but reviewers indicate only being able to taste plum and apricot.

If you have been thinking of growing fruit trees in your yard, plums and these special hybrids are a good choice. They typically don’t require regular spraying to control wormy fruit pests and they are susceptible to fewer disease problems than most other types of stone fruit. Plus, many of the hybrids can be kept relatively small (under 10 ft), with proper pruning.

Dave Wilson Nursery is a wholesale nursery that serves as the primary US propagator for cultivars developed by Zaiger’s. They market these hybrids to both commercial orchard and home garden markets.

If you are wanting to give these hybrids a try, you can find some of the Zaiger cultivars through Raintree Nursery along with a wide variety of other fruits, nuts, berries, and ‘unusual edibles.’ Raintree is retail mail-order nursery located in Morton, WA at http://www.raintreenursery.com/. Their catalog will indicate if you need a pollinizer to plant along with the cultivar you have selected.

There is already a nectaplum, I wonder what is next?

Note: What is a pollinizer and why do you need it? Some types of fruit trees (apple, pear, sweet cherry, and Japanese plum) require the transfer of pollen from the male part of the flower of one cultivar to the female part of a different compatible cultivar of the same type of fruit tree. The tree providing the pollen is the ‘pollinizer.’ If this transfer does not happen, fruit will not develop. Other types fruit trees are self-fruitful and do not require the transfer of pollen from one cultivar to another. However, most self-fruitful types (apricot, European plum, tart cherry, peach, and nectarine) will develop more fruit if there is a pollinizer available.

Published: 9/12/2014 12:22 PM

REAL PUMPKINS FOR CARVING

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- OCTOBER 3, 2014

REAL PUMPKINS FOR CARVING

Ever wonder what’s the deal with giant pumpkins? This year the first place pumpkin at the Washington State Fair in Puyallup weighed in at 1609.5 lb and was grown by Stan Pugh of Puyallup. Purists might argue that these are not really pumpkins but a type of winter squash. I tend to agree, but the term “pumpkin” is subjective.

The pumpkins that folks typically make into jack-o-lanterns have smooth orange skin. The fruit is somewhat ribbed and the stems are furrowed and woody. Botanically they are members of the genus Cucurbita and the species pepo. Cultivated varieties (cultivars) of what I think of as pumpkins are a subgroup of Cucurbita pepo. Other subgroups of Cucurbita pepo include summer squash, acorn, spaghetti, delicata, and ornamental gourds.

The gargantuan giant “pumpkins” grown for fairs and festivals around the country are a subgroup of a different genus, Cucurbita maxima. They tend to have orange or orangish skin with ribbed fruit. Their stems are spongy without ribs. Other true winter squash in Cucurbita maxima include blue Hubbard, banana, buttercup, turban, delicious, and Kabocha squash cultivars.

Yet another species of winter squash, Cucurbita moshata, has some cultivars dubbed “pumpkins.” Generally, C. moshata pumpkins have deeply ridged stems that flare out at their base. The skin may be orange, buff, or green, and the flesh is dark orange and dry. These are type used for making canned pumpkin and pumkin pie. Butternut squash are in a different subgroup of C. Moshata.

Carved Pumpkins: Every fall my children and grandchildren delight in carving pumpkins, the type I call real pumpkins. They go to a lot of work digging out the gooey guts and deciding on carving designs. After all that work, it seems a shame that the pumpkins start to shrivel and mold within a few days and are usually goners a week after carving. I researched credible recommendations regarding how to prolong the life of carved jack-o-lanterns.

Parden the pun, but once pumpkins are cut they are “ripe” for rot. The cut surfaces allow easy entry to molds and rot fungi into the flesh. One simple step in preserving pumpkins is placing placing the carved pumpkins where they will stay cool and out of direct sunlight during the day. Dedicated carvers recommend store prized specimens in the refrigerator to slow down the decay process. Carvers also recommend against placing your pumpkins directly on concrete as this will draw moisture out and lead to quicker shriveling due to moisture loss.

An Illinois Extension educator suggests dunking or spraying the cut surfaces with a 20% bleach solution and blotting it all dry. However she did not offer any proof that it works, so I am skeptical of that approach.

There is also a product available on-line called Pumpkin Fresh containing a borax solution and they indicate it “preserves and protects” and “fights mold and rot.” It is sprayed on the inside and cut surfaces daily to discourage fungi. I find the results of a school science project where a student tested both bleach and Pumpkin Fresh against the control. The “winners” in overall longevity were the control and the Pumpkin Fresh but one had more mold and the other more rot and both were pretty shriveled after two weeks.

I might get some and give it a try this year. Of course that means carving two pumpkins, one to be used as a control. I’ll let you know if it works.

Published: 10/3/2014 12:13 PM

IS IT APHIDS CAUSING THESE CURLED LEAVES?

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- MAY 30, 2014

IS IT APHIDS CAUSING THESE CURLED LEAVES?

‘Help! My plant has curled leaves. What’s wrong?’ This is a question that I often get asked, but there is not an easy answer. Curled or distorted leaves can be caused by more than one thing. Aphids, weed killers and plant viruses all cause malformed leaves on plants.

You might think that aphids would be the easiest of these to diagnose. All you have to do is look for these little plant suckers inside the curled leaves. Aphids are pear-shaped soft-bodied insects that are fairly small, ranging in size from less than 1/16 inch to more than 1/8 of an inch long.

Aphids can be green, yellow, gray, pink-purple, or even black aphids. Typically, aphids are found in groups on tender new growth and buds. Their numbers can build up quickly because early in the season all the aphids are females that give birth to live females that produce more females and so forth.

Aphids feed on plants by sucking out plant sap with piercing, sucking mouth, sort of like a straw in a juice box. When aphid numbers are small, they don’t do much damage to plants, but large populations can stunt plant growth. Some aphids also inject a toxic saliva into the plant that causes distorted growth. These curled leaves then provide the aphids with protection from some predators and pesticide sprays.

Two aphids that often cause severe leaf curl in area gardens are the green peach aphid and the wooly ash aphid. However, when gardeners uncurl malformed leaves to look for these aphids, they may not find them. That is because the aphids have departed their early spring hosts and moved to summer hosts before they return in the fall. The green peach aphid which attacks plums, peaches, and nectarines in early spring spends the summer on weeds and vegetable crops.

The wooly ash aphid has a body covered with waxy secretions that makes it look ‘wooly.’ These aphids feed on new growth of ash trees in the spring and then spend the summer on the roots of the trees. They move back to the top of the trees to mate in fall.

In the past, when gardeners encountered clusters of aphids on their plants they would rely on chemicals to help manage the problem. Today, gardeners are encouraged to try non-chemical approaches first before using pesticides.

– Avoid applying high levels of nitrogen fertilizer which promote excessive vegetative or lush soft growth that favors aphid feeding.

– Knock aphids off a plant using a forceful stream of water, taking care not to the plant. The aphids will not climb back onto the plant.

– Learn to recognize and encourage natural predators and parasites that feast on aphids.

– Control ants feeding on the honeydew (sugary plant sap) secreted by the aphids. They actually protect aphids from predators.

If you do decide to use a pesticide spray, avoid broad spectrum insecticides that will also kill aphid predators. Insecticidal soaps and horticultural oils will effectively control aphids present and visible on plant shoots and leaves. These are contact insecticides and must come in direct contact with the aphid bodies to be effective. Because many aphids feed on the bottom sides of leaves, be sure to get good coverage when using these materials. Most aphids that feed on woody plants early in the season, such as the green peach aphid and the wooly ash aphid, are best controlled with delayed-dormant sprays in late winter just as the buds start to open.

Published: 5/30/2014 11:53 AM

NOT AN INSECT BUT STILL A PESKY NUISANCE

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- MAY 23, 2014

NOT AN INSECT BUT STILL A PESKY NUISANCE

Some years certain insect populations will generate concern with a sudden spike in their numbers. This spring, one such creature causing some worry is the clover mite. Technically this large mite is not an insect. It is an arachnid and is more closely related to spiders, ticks, and scorpions. As a group, arachnids have eight legs, no wings, and two body sections. Adult insects have six legs, three body sections, and most also have wings.

Let’s get back to our clover mite problem. These mites are very visible, being just a little smaller than the head of a pin. Their body pigmentation is bright brick red turning to a reddish brown as they grow older. They have eight legs, but at first glance the front legs look like antennae because they are longer than their other six legs.

Clover mites feed by sucking out plant juices from the leaves of mostly grass and clover, but they may also feed on low growing ornamental plants. They do not bite humans or other animals. The plant damage caused by their feeding is characterized by stippling or meandering silver streaks in leaves. It is usually not severe enough to harm a plant or even be noticed by gardeners. However, clover mites can become a nuisance when they accidentally enter homes. Indoors they are annoying because they cause a reddish stain when crushed.

To understand their periodic “sudden” appearance let’s talk a little about their life cycle. Clover mites spend the cold winter and hot summer months mostly in the egg stage. They hatch from eggs in the spring and fall when temperatures are between 70 and 85 degrees. After hatching, they feed on plants and proceed through three stages of growth before becoming egg-laying adults. There are multiple generations each year.

In the fall, clover mites try to find a protected spot to spend the winter. This cosy spot may be somewhere outdoors or within the outside walls of the home. When looking for an overwintering spot, some mites may accidentally enter the house. In the springtime when sun warms up outside walls of the home, especially south and eastern facing sides, the overwintering mites within the walls can become active and again accidentally come inside. Clover mite invasions are usually most severe when grass and weeds are allowed to grow up close to a building, especially where the grass is lush and heavily fertilized.

Indoors, clover mite control is best accomplished using a vacuum to suck the critters up without squashing them or wiping them up carefully with soapy water and a sponge. On the outside of a building or structure, simply squirt them off with soapy water. Any of the insecticidal soaps should work well, but make sure whatever you use does not stain the finish.

To prevent future outbreaks, consider not allowing grass to grow up next to the foundation by creating a two feet or more deep landscape bed around the home. To help with weed control, mulch this “grass free zone” with a three to four inch layer of bark or pea gravel. You may also want to make the bed deeper and plant it with ornamental shrubs and flowers.

It is also a good idea to “tighten” up your home by caulking outside cracks and crevices around windows, doors, and the foundation. This is helpful in preventing clover mites, spiders, and other pesky insects… and non-insects from becoming a nuisance indoors.

Published: 5/23/2014 11:51 AM

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

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