Washington State University Extension

Garden Tips

Archive for September 2015


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written August 30, 2015


Having been at this job for over 30 years, I have seen gardening trends come and go. Way back in the 1980s there were numerous local gardeners interested in food gardening, growing both vegetables and tree fruit in their backyards. You could always find a large variety of vegetable transplants available at big box stores, as well as at local nurseries.

In the 1990s things started to change, fewer and fewer gardeners were interested in growing their own produceThe big box stores changed to offering fewer vegetable transplants, instead focusing primarily on colorful annual flowersI am not sure if this happened because gardeners realized that gardens and fruit tree were a lot of work, they had easy access to fresh produce from local farmers markets, their busy lives did not allow much time for gardening, or a combination of all these.

I am happy to say we have now come full circle and gardeners, especially younger gardeners under the age of 50, are interested in food gardening againThe focus is on veggies and herbsA survey taken by Today’s Garden Center indicates that these “youngsters” say gardening gives them a sense of accomplishment, allows them to become more self sufficient and have more control over the safety of their food, and provides a way to get children outside and teach them about nature. Wonderful!

Another thing to know about younger gardeners is their interest in food and cookingThere is a proliferation of television cooking shows that are enjoyed by both young adults and older folks like meBecause the All-America Selections (AAS) organization has noticed that cooking fresh foods is “trending,” they plan to market their 2016 winning herb and vegetable selections with five videos that demonstrate cooking techniques.

With the home garden focus back on vegetables, many of the big seed companies are strongly marketing their new vegetable varieties, especially ones with more compact growth habits that are easier to fit into the smaller gardens of today’s gardeners. These are a few that have already hit the market or will be arriving next year:

Basil ‘Docle Fresca’( is an AAS 2015 winner that is a “new and better” compact Genovese basil plant with sweet tender leaves and growing only 10 to 14 inches tallIt is drought tolerant and a good container plant

Pea ‘Masterpiece’ ( a pea that Burpee calls a “triple treat” with edible tendrils, pods, and peasGrowing up to 30 inches tall and 32 inches wide, these pretty peas plants work well in containers and limited-space gardens

Kale ‘Simply Salad Kale Storm’ (, is a mix of salad kales that are slow to boltThe seed combined into single pellets is a mix of different leaf textures and colorsNot only will this work well as fall cool-season crop for container growing, it will also serve as an attractive ornamental during the fall months

Tomato Heirloom Marriage Series (PanAmerican Seed) is a series of tomato hybrids that are the results of crosses between two heirloom varieties to create an F1 hybrid variety, “marrying” the best characteristics of each parent for improved performance in the gardenOne already available (along with others) is ‘Big Brandy’ whose parents are ‘Big Dwarf’ and ‘Brandywine’ Coming in 2016 is ‘Marzinera’, a cross between ‘San Marzano’(my new favorite tomato) and ‘Cream Sausage.’

Zucchini ‘Brice’ (no retail seller available ) is a zucchini that produces 3 to 4 inch light green round fruit on compact plants with attractive mottled leavesIt is more manageable than many zucchini and is great for container or limited-space gardeningThe fruit can be hollowed out for stuffingYummy!

This season isn’t even over yet and I am thinking about next year. Whoa!


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written August 20, 2015


The last time the Tri-Cities was inundated with armyworms was two years ago. These caterpillars are cyclic, appearing only some years in late summer and early fall. They can be a problem feeding on garden crops and lawns, but they usually concern homeowners because they travel in masses, pretty much like an “army.” Entomologists note that armyworms, climbing cutworms, cutworms, and fruitworms are larvae of closely related night-flying moths in the Noctuid family. These moths are sometimes called “millers” by non-entomologists.

What sets armyworms apart from their close relatives is their timing and their feeding in large groups rather than individually. The Western yellow striped armyworm (WYSA) is common in Washington and is sometimes a pest in field crops, particularly in alfalfa. WSU entomologists note that they can “be serious pests…, especially in early fall following a hot dry summer which concentrates the larvae into “armies”.”

With three possible generations over the summer, WYSA numbers can grow over the spring and summer months. Add to this the knowledge that the WYSA generally do not overwinter well because cold winter temperatures kill their eggs, larvae, and adults. However, dry mild winter conditions allow more of them to survive the winter, leading to a buildup of their populations. Well, we have had a hot dry summer so far and several relatively mild winters, so I would not be surprised if armyworms may become a problem again this year.

One local resident has already noted these caterpillars traveling en masse onto her back patio. A mature caterpillar is about 1.5 to 2 inches long. Its body is a blackish color with two thicker yellowish longitudinal stripes lengthwise down its back and numerous narrow stripes on its sides.

While these armyworms may prefer eating alfalfa, they will get hungry when the alfalfa is cut and move out of the field and nearby weedy areas into surrounding areas in search of food, ending up in your yard, garden, or patio. They feed primarily on the leaves of various crops and weeds, but may also feed on other plant parts. Usually the damage they cause with their feeding in yards and gardens is not significant, but their large numbers can be alarming.

When faced with an armyworm invasion, the first inclination is to apply a non-organic insecticide in a blanket application, spraying large areas of the yard. Dr. Doug Walsh, WSU Entomologist, says a blanket application is also likely to kill a number of the armyworms’ natural enemies, like “bigeyed bugs, spiders, minute pirate bugs, damsel bugs, lacewings, and at least a dozen species of parasitic wasps.”

Walsh indicates that an application of spinosad, an organic pesticide, would be less toxic to these natural enemies and should help control the armyworm population. Using a spinosad product would also be safer for your family and your pets.

There a number of home garden products containing spinosad, including Bonide’s Captain Jacks Deadbug Brew, Green Light Lawn and Garden Spray, Monterey Garden Insect Spray. Of course if you only find one or two of these caterpillars in your house or around the yard, simply handpick and squish them.
With only one sighting of these creatures, this may be a false alarm but I want you to be prepared to deal with any invading armies of caterpillars.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written August 13, 2015


Remember a few weeks ago when I talked about the elm seed bug, a new invasive insect getting in area homes? Now a number of home owners are finding another bug inside their homes. The masked hunter bug is not new to our area, but usually only one or two are brought to me for identification each year. However, I have recently been seeing an increasing number of them.

The masked hunter bug is one member of a group of bugs known as “assassin” bugs. Coming here originally from Europe, the masked hunter bug is not native here, but it is common throughout the US. As a true bug, the masked hunter has an elongated shield-shaped back with an “X” pattern on its back created by its folded wings. The 3/4 to 1 inch long adult masked hunter is a shiny brown-black color with no colorful markings. The young nymphs (immature stages) look similar, but often “mask” themselves by covering their bodies with dirt and dust particles.

You will probably not notice another important physical characteristic, its short beak or “proboscis” tucked under its body. When feeding this beak allows it to stab, paralyze, and suck out the body fluids of its prey. When inside a home masked hunters are seeking food which can include a variety of insects, including bed bugs, bat bugs, and swallow bugs. They are effective “assassins” because they are nocturnal, hiding during the day and coming out at night looking for food. In addition, the dusty coating of the nymphs is great camouflage.

While they are considered beneficial because they eat other insects, masked hunters are not benign and should not be handled. Its bite can be painful and has been compared to a wasp or bee sting and may result in some swelling. While occasionally a masked hunter may bite if unprovoked, most human bites are made in self-defense.

It may be reassuring to know that masked hunters tend to travel alone wandering from one place to another. If you do not have a large number of insects in your home, you are not likely to encounter one or more masked hunters. While “beneficial” they should not be considered an effective method of pest control. Carefully get rid of any you find indoors.

To prevent more from being attracted to your home, look for any other possible insect populations and control them. Make sure you do not have any swallows or bats roosting in or near your home. Thoroughly clean and keep clean places the masked hunter can hide, such as under beds, along baseboards, in corners, or any place else dust collects.

Outside, tighten up your house with caulking if needed. If you leave outdoor lights on at night, change to low pressure sodium lights. Research indicates that yellowish sodium lights attract fewer insects and spiders than other types of lighting.

Another type of assassin bug found in the US is the conenose or “kissing” bug. These bugs feeds on the blood of mammals and the kissing bug’s bite and can transmit Chagas disease, caused by a parasite, to humans, dogs and small animals. This disease, primarily found in the Southwest and Central America, is not transmitted by masked hunter bugs and is not found in our region.

I wonder what insect will be “bugging” us next?


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written August 6, 2015


Most gardeners I know are concerned about the environment and would be upset to learn that about half noxious weeds in this country were introduced by gardeners like themselves. Gardeners are always excited to find an interesting or unique new plant for their yards and gardens. Unfortunately, some of these plants escape the confines of the garden and wreak havoc on wildlife habitat and agricultural lands.

One of these escapees is Ravenna grass (Saccharum ravennae), a large “ornamental” grass, also called “hardy pampas grass” or “plume grass.” It is so named for its resemblance to pampas grass, forming large 3 to 4 feet diameter clumps and producing 12 feet tall flowering stems topped by attractive silver feathery plumes. Unfortunately, the plumes produce plenty of minute seeds that are easily in spread wind and water.

Ravenna grass proliferates in gardens, irrigation drainage ditches, wetlands, and riparian areas where it can crowd out habitat, create impenetrable areas, and restrict stream flow. It could become a problem in eastern Washington along the Columbia and Yakima rivers and is already a serious problem in many other western states.

Where did it come from? Ravenna grass is native to the Mediterranean region and has been sold by the horticulture industry since about 1921 as a desirable ornamental grass. In fact, a quick search of the internet indicates that you can still buy it. Fine Gardening magazine touts its height as a striking vertical accent for the landscape and notes that it is deer, drought, and frost tolerant. Nevertheless, do not to buy it or plant it. It will spread via the seeds and become a weed problem in your yard, your neighbors’ yards, and beyond.

Our local Master Gardeners unsuspectingly planted some Ravenna grass several years ago in the Ornamental Grass garden of their Master Gardener Demonstration Garden. It thrived and spread itself throughout the entire garden and the neighboring library landscape. They were clued into this invasive grass by a local noxious weed board employee who advised seeking out all the plants in the garden and digging them out. (Ravenna grass is classified as a Class A noxious weed by the Noxious Weed Board of Washington, requiring all of us to remove it from our land.)

Before they could attack the Ravenna grass infestation, the Master Gardeners needed to know its identifying characteristics. Without the flowers or seed heads, it is often hard to tell one ornamental grass from another. However, Ravenna grass leaves are distinctive with a white mid-vein running the length of the 0.5 to 1 inch wide and 3 to 4 feet long blades. The blades are blue-green in color with very hairy bases.

Once they knew what it looked like, the Master Gardeners were ready to attack the grass by digging it out the plants and their roots because that is the most effective method of control in gardens and landscapes. There are not yet recommended chemical control recommendations for controlling Ravenna grass in home gardens.

The Master Gardeners found and removed over 200 smaller plants not yet producing flowers and seed along with the offending larger plants originally planted in the Ornamental Grass garden and responsible for the problem. They averted a noxious weed disaster in their garden, but this grass was unknowingly bought and sold to many other gardeners in our state before nurseries were made aware of the problem. If you have “hardy pampas grass” in your landscape, check it out, and get digging if you find that it is Ravenna grass. For more information on Ravenna grass consult the Noxious Weed Control Board of Washington at:


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written July 30, 2015


We had a brief respite from the hot weather this past week, but now it is back. I am hoping that my garden tomatoes will have set more fruit during the cooler weather. I have been able to start harvesting a few ripe tomatoes, but alas many of these tomatoes are cracked.

Cracked Tomatoes: After a long wait for ripe tomatoes, it is disappointing that many have radial cracks or splits in the skin starting at the stem. This occurs because the flesh of the fruit grows faster than the skin. Temperatures over 90 degrees or temperatures fluctuating widely between day and night can lead to cracking. It also can be attributed to heavy pruning when staking tomatoes. This exposes the fruit to light and increases the temperature of the fruit.

Uneven watering, fluctuating between very dry to very wet soil, can also give rise to tomato cracks. Heavy nitrogen fertilization causes very fast vine growth, also causing more fruit to crack.

Finally, some varieties are more prone to cracking. A number of the heirloom varieties, like Brandywine, are notorious for their tendency to crack. That is one of the reasons why modern hybrids were developed. For example, Burpee developed their hybrid Brandy Boy to have the same great taste of Brandywine without the problems, including cracking, associated with growing this heirloom.

The problem with cracked tomatoes is that the cracks in the skin make it easy for secondary fungi and bacteria to infect the fruit. The appearance of mold, extremely soft fruit, or liquid leaking from the tomato are sure signs of infection. Discard them. You can eat cracked fruit that are not infected, but do so quickly because they will not last long.

Blossom Drop: Astute veggie gardeners have noted the lack of beans on their bean plants and attributed it to the heat. When temperatures climb well above 90 degrees, beans and peas will drop their flowers without setting fruit. The same often happens with tomatoes and peppers too. The reason for “blossom drop” and the lack of fruit involves pollination and the subsequent fertilization of the embryo in the ovary within the flower.

You might think the reason for this is that bees are not active in the garden when temperatures are above 100 degrees, but beans, peas, tomatoes, and peppers are self-pollinating and thus do not depend on bees or other insects to enable pollination and fertilization. However, these self-pollinating flowers do need wind or insects to shake the pollen from a male part of the flower (anther) onto a female part of the flower (stigma).

What about the veggies that do require an assist from bees and other pollinating insects? Fruit production of cucumbers, melons, and squash seems to slow in hot weather too. Aborted or misshapen fruit are because bees are not very active in the hot weather and because pollen does not remain viable for very long.

We can not do anything about the hot weather, but we can reduce plant stress and minimize cracking and blossom drop by keeping the garden soil evenly moist, mulching to cool the soil and conserve moisture, and not applying excessive amounts of nitrogen fertilizer. It’s also a good idea to provide bees with some moisture. Turn a bird bath or large pot saucer into a bee bath by filling it with coarse gravel or river rock and adding water. The stones are used as perches, so the bees will drown in the open water.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written July 23, 2015


Did you ever wonder why it seems like some weeds grow even faster in hot weather? It is because they do!

Growth of cool-season turfgrasses, like Kentucky bluegrass and fine fescues, slows during the sweltering heat of summer. However, some weeds are able to make the most of the heat and sun because they have a different type of respiration and function better when temperatures are between 85 to 117 degrees. Some of these warm-season weeds are Bermuda grass, crabgrass, foxtail, goosegrass, purslane and prostrate spurge.

I hate crabgrass because it sticks out like a sore thumb with its lighter green leaves and rapid growth, making it very obvious that there are major crabgrass infestations in many local lawns this summer. How could this happen despite applying a crabgrass “preventer” or preemergent herbicide? Even if the herbicide was applied at the recommended time, spring temperatures fluctuated up and down and may have thrown off the timing and resulted in applying the material too late or too early. If applied too early, the material may have lost its effectiveness before the crabgrass germinated.

Failure to control crabgrass could also be due to a lack of good coverage or not using the right rate. Always be sure to calibrate your sprayer or spreader before application. For more even coverage, apply half the amount of herbicide in one direction and then apply the other half in the direction perpendicular to your first pass.

A healthy dense turf is the best protection against crabgrass. Last summer’s extraordinary heat was tough on lawns and resulted in thinner turf that is now being stressed again by excessive summer heat and in some areas severe drought stress. Keep in mind that the grass in most lawns is comprised of cool-season turfgrasses that actively grow during the cooler months (March, April, May, October, and November) of the growing season. With the extraordinarily warm fall last year and very warm spring this year, many lawns have not been able to fully recover.

When (and if) cool fall weather arrives, fall fertilization at the recommended times of early September and early November will be important for green lawns that have made it successfully through the summer. However, only fertilize if there is adequate water available and the grass is green and growing.

A number of local residents have also been noting the proliferation of prostrate spurge in their lawns and gardens. There are four types of prostrate spurge, with spotted spurge being the most common in this area. These low-growing plants have tiny leaves and form a prostrate mat along the ground. As members of the Euphorbia family they have a milky sap that can cause skin irritation.

Spurge grows best in dry open areas and takes advantage of bare garden soil and dry lawn edges. In the garden or landscape, I recommend pulling or hoeing for spurge control. In lawns, you can kill spurge with an application of a “spurge killer” herbicide containing triclopyr, but you may find it easier just to dig up the plants if you only have a few here and there.
Of course, the weeds are the only green plants in some lawns where there has been restricted watering this summer. In a few weeks we will discuss what, if anything, can be done to bring these lawns back from the brink of doom.


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


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

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

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

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

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

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

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

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

Those are my top five. What are yours?


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written July 9, 2015


I have several colleagues who are entomologists. They are quick to teach novices like me that all bugs are insects, but all insects are not bugs. “True” bugs belong to the order of insects called Hemiptera and have several characteristics in common. One easily recognizable shared characteristic is a shield-shaped back that is created by their folded front wings. This also creates a triangle shape or “X” pattern on their backs.

Another common characteristic is their highly modified mouth or “proboscis.” It is a long nonretractable hardened tube or “beak” that allows them pierce plant parts and suck out plant or animal fluids. Plant bugs feed on a variety of plant tissues, but seed bugs are a specialized group of plant bugs that feed on the seeds of plants, enabled by their exceptionally long proboscises.

Seed bugs are not a concern in our yards, gardens and homes because they only feed on the seeds of plants. They do not attack humans and do not damage plants. However, they do become bothersome when their numbers become exceptionally large or when they migrate into homes in search of an overwintering spot in the fall or sometimes during the summer for protection from the heat.

Boxelder bugs are a well known seed bug that are often a major annoyance in our area. With their ½ inch long black body, black legs, and bright orange-red markings and “V” on their back, they are easy to identify. While they will sometimes feed on other trees and shrubs, they primarily attack the seeds of boxelder and other types of maple.

New on the local scene is a much smaller, nondescript seed bug, the elm seed bug (ESB). It is brown and about 1/3 inch long. If you look very closely (it is small) you can see lighter colored bands around the edge of the wings and a small black triangle on its shield-like back.

With greater magnification, on the underside of an ESB’s body you would note a long beak at least 1/3 the length of the body. This beak allows it to feed on its primary source of food, elm seeds. They certainly can find plenty of food in our region with the large number of invasive Siberian elms (Ulmus pumila) that produce copious seeds.

The ESB was just discovered in our area last fall when Dr. Mike Bush, WSU Extension Entomologist, confirmed its identity. The ESB is considered an exotic invasive pest and was first discovered in the U.S. in 2012 in Idaho. This summer it is being noted in large numbers here.

Pesticides are of little value in controlling ESBs and boxelder bugs in and around the home, but a perimeter spray application of pesticide may help decrease the population. Extension experts, like Bush, recommend pest-proofing your home by caulking cracks, plugging potential points of entry, and repairing screens instead of using pesticides. Also, cover outdoor vents to the home with mesh screening that allows for air movement but is fine enough to keep the bugs out.

Both these bugs have an unpleasant stinky odor that is released when crushed. This odor can “stink” up an indoor vacuum, so use a shop-vac inside and outside the home when vacuuming them up. Before starting, add some soapy water to the shop-vac canister to drown the bugs as they are sucked up and empty it immediately when you are done.

So, what is bugging you?


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty for the Tri-City Herald, Kennewick, WA
Written July 2, 2015


I was trying to be optimistic and have avoided talking about the affects of all this extremely hot weather on our landscape and garden plants. However, continued record high temperatures in the region and some of the “warmest months” on record have compelled me to talk about the affects of heat on plants.

Perhaps you can recall learning about how plants take the sun’s energy via the process of photosynthesis to create carbohydrates. The carbohydrates provide the energy for plant growth. The rate of photosynthesis increases with increasing temperatures up to a point. Once temperatures reach about 95 degrees, the rate of photosynthesis decreases.

At the same time, higher night temperatures increase a plant’s rate of respiration. Respiration is the process that breaks down carbohydrates to provide the plant with energy. As a result of decreased photosynthesis and increased respiration, the plant has to start using its energy reserves. Sugars and other carbohydrates that would ordinarily be used for plant growth and the development of fruit are used to keep the plant alive. Plant growth slows to a stop along with the production of flowers and fruit.

However, there is more to the story. Plants use the process of transpiration to cool themselves, similar to our bodies producing sweat. Transpiration involves the absorption of water by the roots. The water then moves up through a plant into the leaves where it changes to water vapor and exits through pores, called stomates, in the leaves.

If a plant does not have an adequate root system or there is little available water, transpiration stops and the stomates close. When this happens, a plant has no way to cool itself. As a result, damage can occur to plant tissues in the form of sunburn or sunscald (large brown blotches), especially on a plant’s south and west sides. Other symptoms of heat damage include stalled growth, leaf drop, and even death.

In addition to the extraordinarily hot weather, many area gardeners are faced with a limited supply of irrigation water. Plus, the hot weather arrived so early in the season that some transplanted trees, shrubs, flowers and vegetables may not have had the chance to grow a root system capable of absorbing adequate amounts of water to keep transpiration going.

The problems brought on by high heat are exacerbated when plants are surrounded by materials that absorb heat, such as dark rock mulches or brick walls, or situated next to surfaces that reflect light onto the plant, such as light colored building walls or white rock mulches.

What does this all mean? If hot weather persists, it means we may see sunscald on vegetable plant leaves and fruit, especially if gardeners are not able to keep the soil moist. Woody plant leaves may exhibit sunscald or leaf scorch (browning of leaf edges and tissues between the veins.) It also means plants are stressed. Woody plants will be vulnerable to attack by borers and other insects. Tree and shrub roots may succumb to dessication leading to dieback of branches from the top of the tree downwards now and in future years.
What can be done? If irrigation water is available, keep garden soil and container mixes evenly moist. Deep water trees. Apply a mulch of wood chips or bark in landscape beds if you don’t already have mulch in place. Mulch veggie gardens with compost or newspaper. Where practical, shade recent transplants during the heat of the day. Finally, hope that this weather moderates and cooler temperatures come quickly.



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