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GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published August 28, 2016

I have to admit that when I relocated to Washington a long time ago, I was deathly afraid of spiders. Since then I have come to appreciate these much misunderstood beneficial arachnids.

Spiders are not insects. They have two body segments, eight legs, and eight eyes. They also have a pair of chelicerae, appendages resembling fangs but serving as jaws. In addition they have a pair of pedipalps, appendages resembling small legs that are used for sensing objects, for helping construct a web, and for holding onto prey. Unlike most insects, spiders do not have antennae or wings, but they are capable of producing silk their entire life.

What makes spiders beneficial is that they prey on insects, providing us with natural pest control. What makes them scary is their appearance and the fact that almost every type of spider is venomous. However, that does not mean they are harmful to us. Generally, most spiders do not possess venom that causes humans any injury. If their venom does cause a problem, it usually just an itchy bite. Out of the approximately 50,000 species of spiders that exist in the world, only about 25 of them are capable of causing human illness and none are considered deadly.

The reason spiders possess venom is to aid them in gaining control over their prey who no doubt try to escape when captured. Spiders are not intent on attacking us and “taking us down” as prey. The most venomous spider in the US is the black widow and it only bites humans when disturbed or threatened.

Spiders take different approaches in capturing their prey which are usually insects. Some build sticky webs and wait for an unsuspecting insect, such as a fly, to become stuck in the strands. As the insect struggles, the spider injects it with venom to immobilize or kill it. Other spiders build webs with dry silk and quickly attack their prey when the vibrating strands alert them of their dinner’s presence. About half of all spider species do not spin webs for capturing prey. Some spiders hunt down their victims, while others sit in hiding to wait for dinner to pass in front of them.

As fall approaches, many homeowners fearful of spiders migrating indoors from outside, will spray their yard and home foundation with pesticide to kill the spiders. This is shameful. Spiders are our friends, eating all sorts of other insects and providing natural pest control just like preying mantids, lady beetles, and other beneficial insects.

This spraying is also misguided because most of the spiders found living inside a home are house spiders, not outdoor spiders. House spiders are ones adapted to indoor conditions that are not favorable to outdoor spiders. House spiders arrive in homes as egg sacs with building materials used to construct the home or on household goods. They spend their lives hidden somewhere within or under the home. When you see them in the early fall roaming about the house, they are in search of females for the purposes of mating.

Outdoor spiders are not well adapted to the limited food and water supply available inside a house. They will stay outdoors, not migrate inside to find a cozy place for winter. They are adapted to surviving winter outdoors. If they get lost and come indoors, they will die.
If you do have a number of house spiders start appearing in your house in the fall, they have come from somewhere within the house. While creepy, it should not cause you sleepless nights. Just buy a bunch of sticky spider traps at the hardware or grocery store and place them along baseboards in the corner of rooms or under the beds. If cobwebs are a problem on the outside of your house or on shrubs, simply brush them off with a broom or use a forceful spray of water to wash them off. Remember, spiders are our friends.

Spiders are much misunderstood creatures. To learn more about spiders go to the University of Washington Burke Museum website that debunks many myths you may have heard about spiders at:


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published August 21, 2016

If you ever hear gardeners talking about green manure you might be wondering just what type of animal produces green manure? It is not produced by an animal. They are talking about cover crops. These are crops planted in the garden and tilled back into the soil primarily for the purpose of adding organic matter, but they also provide additional benefits. These other benefits include the reduction of soil erosion from wind and water, the relief of soil compaction by crop roots, the discouragement of weeds by shading, and decreased nutrient loss over the winter by temporarily tying up of nutrients.

I do not know many area vegetable gardeners who plant cover crops, but they should consider it. Late summer through early fall, mid-August to mid-September is a good time for area gardeners to seed a cover crop in the garden. This is early enough to give them time to grow before cold weather begins and while irrigation water is still available.

There are different types of cover crops that can be used in gardens or on farms, including grains, grasses, legumes, and broadleaf crops, each with different benefits and management techniques. For home gardeners, an important consideration in the selection of a cover crop is how easily it can be worked into the soil next spring. Unlike farmers that utilize cover crops, most home gardeners do not have tillage equipment that makes it easy to incorporate the plant material into the soil.

Home gardeners will want to pick a crop that grows quickly and can be easily worked into the soil. Some cover crops may get too tall to easily work them into the soil without cutting them first. Depending on the crop, gardeners can use a rotary mower (without the mulching attachment), a string trimmer, scythe, or grass whip for cutting the crop down.

If you want to give cover crops a try, you do not need to end your vegetable gardening season early and remove plants that are still producing. Cover crops can be planted between rows or plants. If you have areas of the garden that are finished producing, remove the plants and seed the entire area.

Leguminous cover crops (vetch, clover, beans, peas) are desirable because they add both nitrogen and organic matter to the soil. However, legumes work in association with a special soil bacteria, called Rhizobia, that take or Afix@ nitrogen that is in the air. If you select a leguminous cover crop, you will need to inoculate the seed with the right Rhizobium species for that crop or purchase seed that is pre-inoculated.

When making the decision of what cover crop to grow, consider the advantages and disadvantages of each. For more information on selection consult the WSU Extension factsheet Cover Crops for Home Gardens East of the Cascades FS117E found at In addition, a good resource on the use and management of cover crops in the garden is Methods for Successful Cover Crop Management in Your Home Garden FS119E at

Once you decide what cover crop to plant, ask your local garden or feed stores if they carry the seed. If not, there are on-line sources of cover crop seed including Territorial Seed Company (, High Mowing Organic Seeds (, and Peaceful Valley Farm & Garden Supply (


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published August 14, 2016

Tree anomalies have a way of occurring from time to time over the years. They are signs of potential problems that justifiably alarm tree owners. Recently, some local tree owners became concerned when a considerable number leaves on their trees started to turn yellow and drop on the ground.

Midsummer leaf drop occurs before the arrival of fall and is usually related to heat stress. As you can imagine, excessively hot days can stress trees, especially species not well suited to hot climates. The root systems of these trees are not able to keep up with the water demands put on the trees by high temperatures. Some types of trees respond to heat stress by getting rid of some leaves, thereby limiting the loss of water through their leaves. Other types of trees develop leaf scorch (brown, dry edges on the leaves) when they cannot keep up with the water demand caused by hot weather.

In our area, sudden yellowing and dropping of numerous leaves due to heat stress has been noticed on birch, cherry, Liriodendron (tulip), linden, sycamore, and willow trees. This year’s midsummer leaf drop was probably more pronounced because of the abrupt change from moderate weather to high temperatures.

Drought stress can also lead to tree leaf drop, especially when paired with heat stress. During hot summer weather, it is important to provide your trees with the water they need via deep watering. Large shade trees seldom receive adequate water when getting moisture only through lawn irrigation. It is important in hot weather to provide trees with a deep watering at least once a week.

How much water do trees need? They need a lot of water because they lose a lot through the pores, called stomata, in their leaves. Adequate irrigation is extremely important. To determine how much water your shade tree needs, go to the WSU Irrigation website and use their Tree Water Management Calculator at

A Supposedly “Fruitless” Plum Tree with Fruit: It can be annoying for owners of a flowering plum tree when their supposedly fruitless plum occasionally or frequently produces a prodigious crop of plums. When this happens, I get asked the same two questions. Why did this happen and are the fruit edible?

The production of fruit on ornamental plums is not a reliable occurrence, but it can happen if their bloom overlaps that of other types of plums. Typically, purple-leaved flowering plums bloom in early spring before other plums are flowering, limiting the possibility of cross-pollination and fruit development. Before buying a flowering plum tree, check with your nursery to make sure the cultivar you are selecting is rarely fruitful in our area.

As to edibility, the fruit can be eaten, but are generally of poor quality for eating. The trees were bred for their beautiful flowers, not their fruit. If you are a thrifty gardener, you might try making jam with the fruit and see if it is tasty enough to be worth your time and trouble. Do not use the fruit if the tree has been treated with pesticides not labeled for use on edible fruit trees.

Garden Note: Whenever applying pesticide to a tree with edible fruit, check the label for the “days to harvest” or the number of days after application that you must wait before harvesting the fruit. Also, make sure the type of fruit receiving the application is listed on the label.


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published August 7, 2016

Kudos to our firefighters for their hard work in fighting the recent wildfires and successfully protecting local homes. Since they do their part in keeping us safe, local home owners should help in the protection of their properties with fire-resistant landscaping. In the short term, there are some easy steps you can take to provide some protection to your home. If your home is situated in an area vulnerable to wildfire, the longer term actions of designing and creating a fire-resistant landscape should be undertaken.

Mulches: Many of you know I favor bark mulches in the landscape because they add organic matter to the soil as they decompose, conserve soil moisture, control weeds, and keep the soil cooler than rock mulches. However, when working to create a fire-resistant landscape, the use of bark or wood chips should be eschewed in favor of non-flammable gravel or rock mulches. Gravel or rock mulches are best especially when mulching any areas that are close to buildings, fences, wood decks, or other wooden structures.

Raised Beds: Raised beds are a big trend in gardening right now, but they are predominantly constructed out of wood. In fire-vulnerable areas, it is better to build raised beds with bricks, concrete blocks, rocks, corrugated metal, or other non-flammable materials.

Landscape Maintenance: While not everyone craves a neat and tidy landscape, yard cleanup and the removal of plant litter is one way to reduce fuel for potential wildfires. So get busy now raking up the layers of dead pine needles and arborvitae foliage beneath these evergreens, dry leaves that have piled up in nooks and crannies around the yard, or bunches of dry plant litter anywhere else. If pines or other needled evergreens are situated close to your house, regularly remove their litter that accumulates on the roof and in gutters.

Keeping potential sources of fuel in mind, be sure to store any firewood 30 to 100 feet away from structures and also keep vegetation away from area. Eliminate any piles of plant litter, such as grass clippings, you may be accumulating. Also, remove dead shrubs and tree branches in your landscape. Cut down weeds and brush in areas of your property that are not landscaped.

Lawns: In regions like ours where the supply of irrigation water is a constant concern, limited areas of lawn are advocated to conserve the amount of water needed to keep grass green during the heat of summer. However, green lawns do resist fire well and efforts should be taken to maintain this green space around your home. However this is not a license to apply water heedlessly. You should still water more deeply, less frequently to save water and promote a healthy green lawn.

Trees: Because I like trees and appreciate the cooling value of their shade, I have ten trees in my yard. If I was in a fire-vulnerable area, I would need to consider pruning off the lower limbs of my trees to remove this ladder fuel. Ladder fuel is plant vegetation, green or dry, that permits fire to ascend into the tops of trees. Pruning off limbs from 6 to 15 feet up is recommended. For the health of the trees, this is best done with proper pruning cuts when the trees are young.

Landscape Design: Creating a well designed “firewise” landscape is very important if your home is situated where it is vulnerable to wildfires, especially if in the wildland-urban interface area. You can help defend your home with sound firewise landscaping. For information on firewise landscape design, go to the University of Idaho’s publication “Protecting and Landscaping Homes in the Wildland/Urban Interface” available at For a list of firewise landscaping plant materials go to:


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published July 31, 2016

While both new and experienced gardeners know that garden soil may benefit from the addition of compost, they do not know about the problems that can arise when from adding too much or using poor quality compost. Let’s take a little time to chat a bit about the pitfalls of adding compost to garden soil.

While good quality compost is considered the holy grail of garden organic matter, there are no set standards for compost. The quality of compost varies with the types of materials composted and the composting processes used. Mature compost is one where the organic materials are fully broken down into stable organic matter. Quality compost is mature compost that is not high in salts, contains no contaminants from industrial waste, has few weed seeds, and can provide plant nutrients.

You can not discern quality compost by looks. If purchasing commercially made compost, ask the seller for a copy of the laboratory analysis provided by the compost producer. Look for the carbon to nitrogen ratio (C:N) that indicates the stability of the organic matter (OM). A ratio between 12:1 to 15:1 is an indication that the OM is stable. If the ratio is less than 10:1, it is an indication that it contains organic materials that are still in the process of decomposing. A ratio above 25:1 indicates that the compost contains high carbon materials that break down very slowly and will tie-up available nitrogen as it decomposes, depriving garden plants of nitrogen and hampering plant growth.

On the analysis look for the EC or electrical conductivity of the compost. This is a measure of the soluble salts in the soil. High soluble salt levels are harmful to plant roots. Compost with an EC above 8mmho/cm are high in salts and should be avoided. It is better to purchase compost with an EC that is between 0 and 4 mmhos/cm.

Also, pay attention to the percent (by dry weight) of organic matter in the compost. If the percentage is lower than 30 per cent, it means that soil or sand have been added to the mix. If higher than 60 percent, it is unfinished or immature compost containing undecomposed organic materials.

Be aware that each batch of compost that a producer makes varies in its analysis. One time the salt levels may be acceptable and the next time they may be too high, so check the analysis each time you purchase compost even if it comes from the same supplier or producer.

While local soils often benefit from the addition of quality compost, it is possible to over do it. Too much compost can cause problems including excess nutrient levels, especially nitrogen and phosphorous, high soluble salts, and excessive levels of organic matter. (Levels of organic matter above 5% to 8% by weight are too high.)

The general rule of thumb when adding compost to the soil in vegetable gardens or annual flower beds is to add no more than 2 to 3 inches of quality, low-in-salt compost to garden. The compost should be thoroughly incorporated into the top 6 to 8 inches of soil before planting. Done annually, the level of organic matter in your soil will increase. To avoid excessive levels of organic matter, reduce the amount of compost you are adding to only 1 inch after three years or get a soil test to determine the level of organic matter in your soil. As with so many things in life, too much of a good thing can be bad. The same goes for compost.

Garden Hint: How much compost do you need to apply one inch to the garden? Three cubic yards will cover 1,000 square feet to a depth of one inch.


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published July 24, 2016

This week I was out weeding in my garden and noted considerable notching caused by root weevils on the leaves of various plants. Root weevils are a common pest in area home gardens but the adult weevils are seldom brought to the Extension office for identification. That is because they are nocturnal, feeding late at night and hiding during daylight hours on the undersides of leaves or beneath debris on the ground. However, you do not have to see one of the critters to know that they are at fault. Root weevil feeding causes characteristic scalloping or small semi-circular irregular notches along the leaf margins.

While some insects feed only on certain species of plants, roots weevils are not as selective. In home gardens they tend to show a preference for rhododendron, lilac, forsythia, peony, rose, euonymus, Japanese holly, blueberries, and strawberries, but they will chow down on over 100 other species of plants. Along with their distinctive notching, another sign of their presence are black fecal deposits found on the undersides of notched leaves.

Because there are at least 16 species of root weevils found in Washington, adult weevils vary in size from 1/8 to 1/2 inch long and in color from black to brown or gray. Based on research done by Sharon Collman, WSU Extension Entomologist, black vine, obscure, and strawberry root weevils are very common in western Washington, but the lilac root weevil is dominant in eastern Washington landscapes and gardens.

So what makes a weevil a weevil? Weevils are a specialized type of beetle. They are somewhat oblong in shape and have hard, crunchy outer wings. What sets them apart from beetles is their elbowed antennae and their specialized mouth parts that look like an elongated snout. Also, the inner wings of most weevils are not well developed, leaving them unable to fly.

So what makes a root weevil a “root” weevil? The creamy-white C-shaped legless grubs or larvae of root weevils eat plant roots. They start out by feeding on fine roots and then may move onto larger roots and even the crown or base of plants. Leaf notching caused by adults is primarily just cosmetic damage, but heavy feeding on the roots by larvae can kill plants.

One control strategy is to avoid introducing root weevils into your garden and landscape by inspecting plants before you buy and avoiding any with the characteristic notching. Root weevils cannot fly. To get from here to there they have to walk or hitch a ride on infested plants, soil, or plant litter.

Once root weevils get started in a yard or garden, it is hard to get rid of them. There are some home garden insecticides available for control of the adults, but generally these materials are not very effective. If you do try chemical control, apply sprays at night between nightfall and midnight when the adults are feeding.

WSU Extension recommends that gardeners manage root weevils by hunting them down after dark. No, I am not kidding. Place sheets or box tops under your infested plants and then go out late at night and shake the branches. The weevils will drop onto the sheet where you can collect and dispose of them. Do this on successive nights until you are not getting any adults dropping off the plants. (You may want to warn your neighbors about this so they do not call the police.)

Another method of control is the application of beneficial nematodes to the soil when the larvae are present. The nematodes are applied as a drench to moist soil when the soil temperature is above 55 degrees. Because of climatic conditions in our regions it may be difficult to effectively control root weevils with nematodes, but some local gardeners indicate they have worked for them.

For more information on the biological, cultural, and chemical control of root weevils go to:


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published July 17, 2016

Vegetable gardening is a lot of work, but it is worth it to be able to pick fresh nutritious produce right from the garden. However, not everyone knows when or how to harvest vegetables at the “peak of perfection.” Since many warm season vegetables are starting to become ripe, let’s talk about harvesting and care of just-picked veggies.

Summer Squash: Zucchini and yellow summer squash are best harvested when they immature and only 4 to 7 inches long. To pick the fruit, cut them off the vine using garden shears or a knife. If allowed to grow larger and more mature, their skin gets tougher and the seeds get bigger and harder. After harvesting wash the fruit with clean water and then use immediately or store in vegetable bin of the refrigerator. They will only store for a week or less.

It is important to harvest your fruit as soon as they reach the right stage because it promotes the production of more fruit. However, you and I know there is always one zucchini on the plant that hides and grows to gargantuan proportions. Sometimes these are thrown out or given away, but creative cooks will remove the hardened seeds and stuff the fruit for baking, chop it up for use in soup, or grate it for adding to zucchini bread or tomato sauce.

Onions: Dry onions are ready to harvest when most of their tops have fallen over. When this happens, it means the onions are done bulbing and will not get any bigger. To harvest, carefully pull them out of the ground and shake off as much soil as possible. In heavier soils the onions may not pull easily so lift them out of the soil using a spading fork. Then “cure” or dry the harvested bulbs in a shaded location with good air circulation. Once their roots are dry and the skins become dry and papery, cut the tops off about two inches from the bulb and store them in mesh bags under dark, dry, cool (32 to 40 degrees) conditions. Keep in mind that sweet onions, such as Walla Walla Sweets, do not store well. Yellow onions store the best, followed by red and white onions. Of course, you do not need to worry about curing or storing the onions if you want to eat them immediately.

Both the green stems and immature bulbs of green onions or scallions are harvested whenever they reach the desired size. Wash green onions thoroughly with cool, clean water before eating. Because they are immature, green onions do not store well and should be kept in the refrigerator and used within a week of harvest.

Cucumbers: Like their summer squash cousins, cucumbers are harvested when they are immature and before their seeds fully develop. Cut them off the vine leaving 1/4 inch of stem attached to the fruit. The correct size for harvesting depends on the cultivar and their intended end-use, with pickling cucumbers tending to be smaller than those cultivars for salads and fresh eating. Check the cultivar seed packet or catalog to find out the correct size for harvesting. Mature cucumbers are undesirable because they have tough skin, bigger seeds, and often a bitter flavor. Harvest your cukes regularly to promote continued bloom and fruit production. After harvesting, wash the fruit and then store them in the refrigerator for a week or less.

Harvesting melons can be tricky, so we will tackle that topic another time.


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published July 10, 2016

I am often asked what the best trees are for planting in our region. However, this query typically includes certain criteria that make my answer more challenging. Homeowners want a tree that does not get too big, does not produce messy fruit or seeds, does not have insect or disease problems, or does not have invasive roots or surface roots. Their ideal tree also has pretty flowers in the spring and attractive fall color, grows quickly, and tolerates our local soils and climate well.

If you are waiting for a list of the trees that meet these criteria, you will have to keep waiting. There are no perfect trees. Every tree has one or more characteristic that is objectionable in some way.

Leaf Litter: If you own a mature sycamore or silver maple, you know that large trees with large leaves produce large volumes of leaves, creating a raking and disposal nightmare in the autumn. Mature large trees can be magnificent. However, when studying what type of shade tree to plant you, may want to consider trees, such as little leaf linden or river birch, with smaller leaves that produce a smaller volume of fall foliage.

Seed and Fruit Litter: Generally, trees are going to produce litter in the form of seeds or fruit. I frequently hear complaints about the massive amounts of seeds produced by some maples and Siberian elm, as well as the seed balls of sycamore and sweet gum trees.

The fruit of ornamental plums, crab apples, and cherries can provide food wildlife, but this fruit can be very messy when ripe and mushy, especially if the tree located close to pavement. Some fruit trees, even ornamental fruit trees, are subject to attack by the cherry fruit fly or the codling moth. County law requires that these pests be controlled even in ornamental fruit trees. This requires regular pesticide applications.

Gingko fruit smells like dog manure and mulberries will turn white tennis shoes permanently purple. Catalpa, Kentucky coffee tree, and honeylocust can create an abundance of bothersome litter with their seed pods.

When selecting trees, look for seedless and fruitless cultivars. For example, the Autumn Blaze maple is a hybrid cross between red and silver maple. It is seedless or pretty much seedless. If you find those spiny seed balls of sweetgum trees a problem, look for ‘Cherokee’ or ‘Rotundiloba’, both virtually seedless sweetgum cultivars. If you like gingko trees like I do, be sure to purchase a male tree, as only female trees produce the stinky fruit. If you like mulberry trees but want to skip the fruit, find Morus alba ‘Fruitless’ that does not produce berries.

Bark and Twig Litter: Some trees, like sycamore, have bark that sloughs off and in some years they can create considerable annoying bark litter. However, this does create an attractive mosaic bark pattern. Siberian elms and birches have a tendency to drop twigs all the time that must be cleaned up before mowing. Since river birch is one of my favorite trees, I am willing to tolerate this annoying tendency.

Nut litter: Mature nut trees, such as walnut, horsechestnut, Chinese chestnut, and oak all produce fairly large hard or spiny fruit. Before planting nut trees, be sure to consider the fruit that will eventually be produced.

There are no perfect trees, but some research before you buy and plant a tree will help you avoid trees that create a mess and more work for you.


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published July 3, 2016

It is simple, I grow flowers in my garden because they are pretty and colorful. It is very disappointing when insects damage or destroy these blossoms. Here are three dastardly pests that are significantly impairing beautiful blooms in my garden.
Thrips: Western flower thrips cause damage to roses and a variety of other flowering perennials. Thrips are very tiny, straw-colored insects that feed on flower petals, often before the buds even open. They use their rasping mouths to scrape at plant tissues and suck up the liquids that ooze out. Their feeding causes streaks and blotches on the petals. If damage is severe, the flower buds may fail to open.
Thrips are difficult to control because their populations build up very quickly. Prune off and dispose of badly infested flowers and buds. Eliminate plant litter and weeds in and around the garden. Avoid using pesticides that kill thrips predators, like lady beetles and lacewings, or that harm bees visiting the flowers. If you decide to apply an insecticide, apply it directly the buds and blooms. Repeat applications are likely to be needed. For effective insecticides, go to:
Tobacco Budworm: The tobacco budworm is devouring all the buds on my petunias, including my beloved Wave petunias, before they even have a chance to open. Aargh! The few flowers that are able to open, are riddled with holes. The adult of the tobacco budworm is an unremarkable greenish-brown moth about ¾ inch long. Like many moths, it is nocturnal, flying, mating, and laying eggs at night starting in late spring to early summer.
On petunias the moths typically lay their eggs on the leaves, but on geraniums they deposit them directly on the flower bud clusters. As soon as the eggs hatch, the little larvae immediately get to work eating flower buds. They will also eat holes in leaves, especially when there are not many flower buds left. Along with the obvious holes in flower petals, buds, and leaves, they deposit their telltale small black frass (poop) on the leaves.
The larvae are hard to detect because young larvae are yellowish-green in color and blend in well with the foliage. More mature larvae vary in color from green to brown, tan, or purple. During the day, the larvae tend to hide in the soil at the base of the plant and then venture out at dusk to feed. When using hand picking for control, look for them at dusk.
As their name infers tobacco budworm is a pest of tobacco, but it also feeds on many other hosts, such as roses, snapdragon, zinnia, verbena, chrysanthemum, marigold, and sunflower. However, its preferred hosts are petunias and geraniums.
Sunflower Moth: The larvae of the sunflower moth also attacks garden flowers. Its hosts are sunflowers and other members of the same family such as daisies, zinnia, coneflower, and cosmos. The larvae of the sunflower moth feed on the flower centers, eating the developing seeds and leaving webbing and frass .
Most home garden insecticides are ineffective against both the tobacco budworm and the sunflower moth. For effective insecticides go to:
When using insecticides for control of tobacco budworms, apply them as soon as feeding damage is noticed. For sunflower moths, apply them when the flowers start to bloom.
I do not like using insecticides in my garden, especially on flowers that are visited by bees and other pollinating insects. As a result, I have switched to plants planted for the colorful foliage, like coleus and sweet potato, but I just cannot give up my petunias!


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published February 14, 2016

Let’s talk about picking strawberries, not harvesting those delicious red berries but selecting which varieties to grow. There are three main types of strawberry varieties, or more correctly cultivars or cultivated varieties. There are June-bearing, everbearing, and day-neutral cultivars.

June-bearers form their flower buds (that turn into the berries) in the fall and produce their one main crop of berries in spring or early summer, depending on the cultivar. Everbearers form their flower buds in the fall and again during summer and produce one crop in spring or early summer and a second crop in late summer or early fall. Day-neutral strawberries form their flower buds all through the growing season, producing a continuous crop of berries with production slowing during the heat of summer.

June-bearers tend to have the largest berries and produce the most fruit over a relatively short period of time. This makes them a good choice for gardeners growing strawberries with the goal of preserving them by freezing or for making jam. Day-neutrals generally produce smaller berries with great flavor over a much longer period, making them a good option for fresh eating.

Another consideration in selecting strawberry cultivars is their winter hardiness. The plants need to be able to withstand the cold of winter in the region they are grown. Some cultivars are very popular in other parts of the country or even other regions in Washington, but may not perform well here. Look for hardy cultivars recommended for growing in the inland Northwest. Here are some of them:

When it comes to June-bearing cultivars, there are a number of possible choices. Benton and Hood are long-time favorites. Hood produces large fruit early in the season and is good for fresh eating or making jam, but does not stand up well to freezing. Benton produces smaller, medium-size berries in late mid-season. They are good fresh and fair as frozen berries. Two other recommended June-bearers are Rainier and Shuksan. They are judged to have the best flavor for fresh eating and are good to excellent for freezing, although Rainier’s berries turn dark rapidly in hot weather.

Popular everbearers recommended for eastern Washington are Quinault, Ogallala, and Fort Laramie. None of these have great size and the fruit is generally not as firm as that of other types.

Day-neutral strawberries are my favorites. Tribute, Tristar, Albion, and Seascape are all recommended for our region. Tribute and Tristar have been around a long time and are dependable. They only have medium-size berries, but their excellent flavor makes up for this. Seascape, a California strawberry, has larger berries with good flavor but the plants are very susceptible to verticillium wilt. This disease can be a problem in local gardens and will shorten the life of a planting. Fern, another day-neutral sometimes seen for sale, is also susceptible to verticillium wilt and has not been tested for production in Washington.

If you want to grow strawberries, now is a good time to start planning what cultivars to plant. Check with your local nursery to see what cultivars they plan to offer this year. Purchase dormant, certified virus free plants for planting in early spring. For more information on growing strawberries in your garden, refer to “Berries for the Inland Northwest” at and “Growing Strawberries in the Inland Northwest & Intermountain West” at They provide information on site selection, planting, and care of garden strawberries.

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