Planning an “Eat the Rainbow Garden”

By Karen A. Mills, Master Gardener

Nutritional resources reviewed by Tina Dodge, OSU Extension

Photo: nadine-primeau-unsplash

It’s time to plan your garden and even start a few early varieties. Perhaps, like most gardeners, you are taking stock of your garden successes and challenges and considering different paths for this year. Have you ever considered planting an “Eat the Rainbow Garden”? An Eat the Rainbow Garden is a garden that produces delicious fruit and vegetables in every color. Clearly, this type of garden would be vibrant, but did you know that creating this type of garden can also support your health?

Growing your own fruit and vegetables increases your access to healthy food, which in times of inflation is more important than ever. Gardening also increases the likelihood that you and your family will eat more fruit and vegetables than families who do not garden. And, when kids are involved in the planning, planting, growing, and harvesting of produce, they are much more likely to have a diet high in fruit and vegetables.

Growing a Rainbow Garden can certainly capture the imagination of kids, but they are just as important for adults. Rainbow Gardens support health exactly because they include all colors of the rainbow. Each color that we see in fruit and vegetables is created by phytochemicals (sometimes called phytonutrients), which are bioactive compounds found in plants that provide color, taste, and smell. Phytonutrients help out plants by protecting them from different diseases and too much sun. Phytonutrients may help people out by supporting our immune system and offering protection against different types of chronic diseases. Every phytonutrient color represents a different compound, each of which comes with different possible health benefits. See the table below for some delicious and colorful options!

Now that we know what an Eat the Rainbow Garden is, how do we build it? Here are some tips to get you started:

  • Location, location, location! It is important to understand your garden site. Get to know your site’s climate, soil, weather exposure, and sun. If you are just starting your garden, this is the opportunity to consider these topics when you select a garden site. Good garden site preparation sets the foundation for a successful gardening experience. For site preparation and selection tips check out: https://extension.unh.edu/resource/preparing-vegetable-garden-site
  • Choose your colors. The colors of the rainbow are red, orange, yellow, green, blue, indigo (a darker purplish blue), and violet (purple). Blue, indigo, and violet phytochemicals are often grouped together, but you can separate them in your garden for a beautiful effect. You can also add to the rainbow by including white, like a cloud! It can be a lot of fun to pick produce based on color. You can choose many different varieties of plants to cover the colors, or you can pick just a few types of vegetables that come in many colors, such as carrots, peppers, tomatoes, or even potatoes! Some examples can be found here: https://fruitsandveggies.org/stories/fruit-and-veggie-color-list/
  • Plan plant placement. Now that you know your garden site and what fruits and vegetables you would like to try, it is time to consider plant placement. It might be tempting to group plants by color in a rainbow garden, however, each plant has its own garden needs. For example, cabbage prefers cool, moist conditions, and cucumbers prefer warm, dry conditions. Even though they are both green, it could be difficult to care for these plants if they are planted next to each other. Check out a resource like https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/ec871.pdf  for what plants do well in what kind of conditions.
  • Consider containers. If you garden on a patio or deck, or if your garden site is limited, consider container gardening. Containers can also be a great add on to an established garden, giving you the opportunity to add a plant that might not quite fit into your garden plan or rotation. Look for varieties that are specifically adapted for containers. Blueberries, cucumbers, tomatoes, leafy greens, peppers, potatoes, strawberries and many other plants have container options. OSU’s Growing Your Own – A Practical Guide to Gardening in Oregon (found here: https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9027.pdf ) contains many basic tips to help you get your garden started including a section on varietals that grow well in containers in Oregon.  Check out this link (https://milwaukee.extension.wisc.edu/2019/06/10/best-container-gardening-vegetable-varieties/ ) for more suggestions on specific vegetable varieties that do well in containers.
  • Want more information? If you are interested in exploring a particular phytonutrient and the foods and health benefits associated with that particular phytonutrient, this is a good resource: https://integrativemedicine.arizona.edu/file/11275/phytoPrevention.pdf . And if you are science savvy, check out this good, very technical resource on phytochemicals: https://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals

Eat the Rainbow Gardens are not only beautiful to see but they can promote healthy eating. With so many colorful fruits and vegetables to choose from, experiment and have fun!

ColorMain PhytonutrientsGarden Options
RedAnthocyanins (including lycopene), antioxidantsApples, beets, cherries, radishes, red onions, red pears, red peppers (bell and hot), red plums, rhubarb, strawberries, tomatoes, watermelon
OrangeCarotenoids (including beta-carotene)Apricots, carrots, nectarines, orange bell peppers, peaches, sweet potatoes,
YellowBio-flavonoids, luteinApples, Asian pears, corn, potatoes (Yukon golds), summer squash, winter squash (acorn, butternut, etc.), yellow beets, yellow bell pepper
GreenCatechins, chlorophyll, flavonoidsAsparagus, Brussels sprouts, bok choy, broccoli, broccolini, cabbage, cucumbers, green peas, leafy greens (chard, collards, dandelion, kale, lettuce, mustard, spinach, etc.), okra, peppers (bell, jalapeno, poblano, serrano), tomatillos, zucchini
Blue, Indigo & Violet*Anthocyanidins, flavonoids, phenolic acids, resveratrolBlackberries, blueberries, eggplant (Italian or Japanese), figs, huckleberries, plums, purple bell peppers, purple cabbage, purple carrots, purple cauliflower, purple grapes, purple kale, purple potatoes
WhiteAllicin, flavonoids, indolsCauliflower, daikon radish, garlic, mushrooms, onions, parsnips, potatoes, turnips,

*Blue, indigo and violet phytonutrients are often grouped together.

Algert, S. et al. (4/1/2016) Community and home gardens increase vegetable intake and food security of residents in San Jose, California. California Agriculture. 70(2):77-82. https://doi.org/10.3733/ca.v070n02p77  Accessed on October 17, 2022.

McManus, KD. (4/25/2019). Phytonutrients: Paint your plate with the colors of the rainbow. https://www.health.harvard.edu/blog/phytonutrients-paint-your-plate-with-the-colors-of-the-rainbow-2019042516501   Accessed on October 17, 2022.

Minich, DM. (2019) A review of the science of colorful, plant-based food and practical strategies for “Eating the Rainbow”. J Nutr Metab. 2019:2125070. doi: 10.1155/2019/2125070  Accessed on October 17, 2022.

Seed Starting Success – Favorite Resources

By Elza Records, Master Gardener Program Staff

A person holds two handfuls of colorful beans. Photo: Filipe Correa, Getty Images.

How do you start your own plants from seed?

What seeds can you plant directly outside, and when?

How you can save seeds from your plants to grow or share?

Here are three research-based resources for seed starting that Master Gardeners regularly share with gardeners in Linn and Benton Counties.

  • Growing Your Own – OSU Extension Catalog is the go-guide for a quick reference seed starting plan for vegetable gardens. Wherever you live in Oregon this publication has a useful start with dates for starting seeds. Inside or out, this guide has all the dates you need. Also available in Spanish, FREE.
  • Propagating Plants from Seed is an in-depth resource for gardeners and small-scale growers. It includes steps to start vegetables, flowers, trees and shrubs from seed.
  • Saving vegetable seeds by the University of Minnesota Extension Service has the basics you’ll need to harvest, clean and preserve seeds for the future.

Trap Crops: what are they and how can they help control pests?

By Carrie Falotico, Master Gardener Trainee

Crucifer flea beetles (Phyllotreta cruciferae) and Brassica juncea, a trap crop that attracts these pests.

Plant pests can certainly be one of the most frustrating parts of growing your own food garden. Trap crops are part of an Integrated Pest Management plan. Here’s how they work. 

A TRAP CROP can be defined as a sacrificial plant that draws away damaging insects from the desirable crop.

Essentially, a trap crop works as an alternative host that draws away invading insects, giving the main vegetable crop an added layer of protection. In some cases, insects have a preference for these alternative hosts, and when given the choice, will go to the trap crop first.  After trap crops are infested with target insects, they can be controlled with timely insecticidal applications or mechanical removal. While trap cropping can be extremely beneficial, it is often not a complete solution. Trap crops will not control all insects and the use of integrated pest management (IPM) is necessary. IPM practices include rotating crops, attracting beneficial insects, and prudently using organic and synthetic chemicals.

This article gives a great explanation of trap cropping for small commercial growers. Many of these practices are also very useful in the home garden and can be done on a smaller scale.

Another great resource that details trap crops as well as intercropping and companion planting, that, when combined with trap crops, can make an even bigger impact when controlling pests.

Identification is key

You will definitely want to make sure you have correctly identified the pests causing damage to your plants. Different pests may prefer different trap crops and may require different integrative pest management (IPM) techniques. This resource is a helpful guide to identifying common pests as well as insects that are beneficial and helpful to gardeners.

Example: Flea beetles 

Flea beetles (including Epitrix spp. and Phyllotreta cruciferae) are a well-known garden pest on crops like kale and broccoli. For flea beetle control, Chinese southern giant mustard (Brassica juncea var. crispifolia) is an example of a trap crop that has been used effectively in the United States to protect crucifer crops from flea beetle damage. In studies conducted at Washington State University (WSU), a diverse trap crop containing Pacific Gold mustard (B. juncea), Dwarf Essex rape (B. napus), and pac choi (B. campestris L. var. chinensis) successfully protected broccoli from the flea beetle. Diverse trap crop plantings combine plants that have different phenologies (life cycles which can be influenced by the environment, weather conditions, and nutrition), chemical profiles, and physical structures that make them more attractive to flea beetles. 

It is important to note, however, that trap crops may not provide complete protection, especially during heavy pest infestations. You also have to manage the pests on the trap crop by removing them by hand and killing them, or using insecticide. Trap crops will be even more effective if several integrated pest management strategies are used together, like 

  • Control weeds in and around planting sites to limit food sources for flea beetles.
  • Remove old crop debris so that beetles will not be able to get protection in the winter.
  • Plant crops as late as possible. Plants grow faster in warmer temperatures and are more stable to resist damage from flea beetles.
  • Use row covers or other screening to keep beetles out when the seedlings are growing.
  • Remove row covers before the flowers come up so pollinating insects can reach the plants.

These articles give excellent detail on managing flea beetles:

Explore more

If you are interested in reading more about Integrated Pest Management and how it can help your garden thrive, this is a great resource

I hope you find this information helpful and that these methods help you have a more enjoyable gardening experience!

Pests In July

Written By: Chad Kuwana, Master Gardener Volunteer Trainee

Black vine weevil
Credit: University of California Agriculture & Natural Resources

Check back in with your azaleas and rhododendrons this summer!

At this point of the year, summer is in full swing and daily high temperatures are consistently in the upper eighties and nineties. The beautiful spring weather that brought about stunning blooms in your garden is just a memory as you try to beat the heat with some freshly picked berries.

While some spring blooms may be holding on, most azalea and rhododendron bushes have lost their flowers and your attention has likely shifted to other parts of your garden like your fruits and vegetables. However, as you water your plants, you might notice notched edges on the leaves or fuzzy white spots on the branches of your azaleas or rhododendrons. These are signs that black vine weevils or scale might be present on your plants.

Black Vine Weevils – Otiorhynchus sulcatus

Description

Black vine weevils are a type of beetle (Curculionidae) about ½ inch (12.7 mm) long. They cannot fly and are mostly black with small patches of white. The larvae are also about ½ inch (1.27 cm) long but are white with a brown head. Adult black vine weevils eat foliage and are most active at night. You will notice notches in leaves from where they were feeding. Larvae, however, feed on the roots of your azalea or rhododendron, so they can cause more severe damage to your plant as it can lead to diseases like Phytophthora root rot.

Damage from the black vine weevil.
Credit: University of California Agriculture & Natural Resources

Life Cycle

The reason you might be noticing evidence of their presence in July and early August is because of their life cycle. Black vine weevils usually emerge between May and June after overwintering in their larvae stage. Upon emerging they need anywhere between 21 and 28 days of feeding before they are ready to lay eggs and begin a new generation. Thus, peak adult populations are seen in the summer. Once they are ready to lay their eggs, black vine weevils can lay as many as 500 eggs over a two to three-week period.

Control

Assuming you don’t have cultivars that are less susceptible to weevils in your garden, there are a few things you can do. 

If you’ve caught it early and the weevil population isn’t overwhelming, you can get rid of the weevils by hand. Once it’s dark (remember they are active at night), you can shake and beat the leaves over a sheet that will collect the fallen weevils and then dispose of them.

Another option is to use corrugated cardboard as a wrap around the trunk (also overnight). This wrap will serve as a trap so that when they seek shelter during the day, you can collect and dispose of them. Instead of a cardboard wrap, you can use a sticky material that will trap the weevils as they crawl up and down the trunk.

Lastly, you can also use parasitic nematodes to help control the infestation at the larval stage.

Azalea (rhododendron) Bark Scale – Eriococcus azaleae

Credit: Michigan State University Extension

Description

Azalea bark scale are small insects about .13 inches (3.3 mm) long. They are red in color but are most recognizable by the fuzzy white sacs on twigs and branches. These egg sacs or ovisacs are important to remove during the summer so they do not hatch. When they hatch in September, the young scale will start to feed on the azalea or rhododendron by penetrating the bark and sucking out sap and will excrete a substance called honeydew. This honeydew will invite sooty mold and fungi to grow and cause your plant to look darkened, yellow, and/or sickly.

Credit: Michigan State University Extension

Life Cycle

The azalea bark scale lay their eggs in early April to hatch in May. During the summer, the young scale will feed and mature to produce the fuzzy white sacs in June and July. This is when you might notice the sticky substance on branches called honeydew and sooty mold covering the leaves. You might also start to see more fuzzy white sacs on the twigs and branches.

Control

Starting with the fuzzy white sacs, you can brush them off with your fingernail or toothbrush. If an area is heavily infested, pruning is the best method for removal. Keep in mind also that fertilizing with too much nitrogen will support the population growth of scale.

Wrapping Up

Hopefully, this post can help you get familiar with these two pests that might be hurting your azaleas and/or rhododendrons. Please reference the resources below for more detailed and extensive information on monitoring and controlling these pests in your garden. It’s easy to forget all the details that go into keeping up your garden so make sure to check in with the OSU Extension Monthly Garden Calendar to help you stay on top of key garden chores throughout the year.

References

Welcome a Rhododendron Into Your Garden This Spring

By Brenda Bye, Master Gardener Volunteer

Unknown Rhododendron Species. Photo by Brenda Bye. 

One of the reasons that I love spring in the Willamette Valley is the masses of colorful rhododendrons. It’s hardly surprising that this flowering shrub is so popular, because it comes in a wide range of sizes and colors. Many species are evergreen which is an additional bonus to add structure to your garden in grey winter months. Spring is a great time to plant rhododendrons and it’s not too late. 

There are about thirty species of rhododendron native to North America. They are found naturally in temperate deciduous forests and enjoy the acidic soil found in these wooded hills and mountains. If you are looking to plant a Northwest native, consider Rhododendron Macrophyllum, the Pacific Rhododendron. Its flowers can range from pale pinks to deep purples. It will grow to be 8 to 10 feet in the garden but can grow much bigger in the wild. 

Another interesting native is Rhododendron Occidentale, the Western Azalea. Its flowers range in color from white to pink, but all have a yellow spot on the upper petals that adds interest and beauty. Their flowers are known to be quite fragrant. Unlike the Pacific Rhododendron, the Western Azalea is deciduous and can have very pretty autumn foliage. 

Regardless of which rhododendron you choose, they require similar growing conditions: 

  • Acidic soil with a pH usually between 4.5 and 6
  • Soil that drains well and is rich in organic matter
  • A consistent level of moisture
  • Dappled shade, although it will tolerate a variety of sun exposures
Smaller rhododendron species, possibly Rhododendron Japonica, the Japanese Azalea. Photos by Brenda Bye. 

Having the right soil conditions is very important before you plant your rhododendron. Many of us in Western Oregon already have acidic soils but if you have questions about getting your soil tested or how to interpret a soil test, I would recommend reaching out to your local OSU Extension Office. You can also reach them online at https://extension.oregonstate.edu/ask-expert.

Rhododendrons can be prone to root rot. That is one reason to mix in a good amount of organic matter into your planting site. Some sources recommend a mix of 50% organic matter. In addition to building healthy soil this organic matter will make sure the roots are getting oxygen and not becoming soggy. Organic matter also helps to feed your plant to keep it healthy. 

Smaller rhododendron species, possibly Rhododendron Japonica, the Japanese Azalea. Photos by Brenda Bye. 

Before you place your new rhododendron in the ground make sure to water it well. When you place the root ball in the ground it should be planted at the same level as it was in the pot. Then mulch it with a thick layer of pine bark mulch, which is good for those acid loving plants. Make sure there is a nice ring of space between your trunk and your mulch to prevent fungal diseases. As the mulch breaks down it will also provide more nutrients to your rhododendron. 

Although rhododendrons have specific soil requirements, they are very easy to care for once planted. The mulch and organic soil you used will help the soil have consistent moisture, but they may need additional watering in the heat of summer. They generally don’t need to be trimmed but do benefit from deadheading spent flowers. Rhododendrons appreciate a yearly fertilizer in the fall and a refresh of their mulch. 

Rhododendrons look great as foundation plantings around your home. Their range of colors will fit into any planting scheme and they will bloom for years to come. If you don’t have one yet, consider planting a rhododendron. 

If you are looking for more information about this flowering shrub, check out the resources of the American Rhododendron Society, www.rhododendron.org. And here is a very in depth article from the Pacific Horticultural Society about the Western Azalea https://www.pacifichorticulture.org/articles/western-azalea-beauty-and-fragrance/

Start your garden with these five resources you can access from home

Birdseye view of person and dog at outdoor table in a garden, working on a laptop.
  1. Start with a research-based introduction to growing food at home. Our favorite is Growing Your Own from OSU Extension. Learn when to plant, how to prepare your growing space, stopping pests and more: https://catalog.extension.oregonstate.edu/em9027
  2. Where can you get garden supplies? Plant Something Oregon has a list of suppliers that offer a range of options for safer shopping. Find them here: https://plantsomethingoregon.com/coronavirus/
  3. Where to get your soil tested? Master Gardener volunteers are not currently able to test soil pH, so gardeners will need to send samples to soil testing labs found in Analytical Laboratories Serving Oregon: https://catalog.extension.oregonstate.edu/em8677

These labs can provide a variety of services. Most home gardeners who are growing plants in the ground will want to check soil pH as well as levels of nitrogen, potassium and phosphorus. Many labs offer the option to request recommendations for amending soil when ordering their tests. Learn how to take a good soil sample to achieve the most accurate results with A Guide to Collecting Soil Samples for Farms and Gardens: https://catalog.extension.oregonstate.edu/ec628

4. Use research-based resources to find garden solutions. OSU Extension offers straightforward tested resources to build resiliency for by growing gardens in this amazing virtual collection: https://extension.oregonstate.edu/gardening

5. Connect with real gardeners to get help! Though our offices may be closed, OSU Extension Master Gardeners are still available to answer your gardening questions by phone or email. Please leave us a detailed voicemail and a callback number. We’re also checking email! Share your photos of plant or insect problems with us. Master Gardeners will research your question and give you a call back or send an email. In Benton County: (541) 713-5000 or email: bentonmg@oregonstate.edu In Linn County: (541) 967-3871 or email: linn.mg@oregonstate.edu

Before Reaching for Pesticides, Get to Know Beneficials – The Good Guys!

By Judi Di Bord, Master Gardener Volunteer

Did you know there is an alternative to controlling pests in your garden by using a pesticide?  Attracting beneficial insects, like lady beetles, green lacewings, praying mantis and dragonflies can help control insects that feed on your plants.  Beneficials don’t just help control pests. Some beneficials are also important pollinators! 

Ladybug (Coccinella septempunctata) on an Common Yarrow's umbel (Achillea millefolium)
Ladybug (Coccinella septempunctata) on an Common Yarrow’s umbel (Achillea millefolium). By Hélène Rival on Wikimedia Commons.

How can you attract beneficials to your garden?  One way is to purchase them at a local garden center and release them into your garden.  You can also attract them to your garden by growing plants to provide an enticing habitat for them.  If you are able to dedicate some space to growing these habitat plants, the rest of your garden can reap the rewards.

Following are some recommendations from the Penn State Extension Service:

  • Carrot Family (Apiaceae)  Plants in the carrot family are especially attractive to small parasitic wasps and flies. Interplant them in your vegetable garden and flower beds. Plants in this family include: caraway (Carum carvi); coriander/cilantro (Coriandrum sativum); dill (Anethum graveolens); fennel (Foeniculum vulgare); Bishop’s flower (Ammi majus); Queen Anne’s Lace (Daucus carota); and toothpick ammi (Ammi visnaga).
  • Aster Family (Asteraceae)  Attractive to larger predators such as lady beetles and soldier beetles. Incorporate into the vegetable garden and flower beds. Plants in this family include: blanketflower (Gaillardia spp.); coneflower (Echinacea spp.); coreopsis (Coreopsis spp.); cosmos (Cosmos spp.); golden marguerite (Anthemis tinctoria); goldenrod (Solidago spp.); signet marigold (Tagetes tenuifolia); sunflower (Helianthus spp.); tansy (Tanacetum vulgare); and yarrow (Achillea spp.).
  • Legumes (Fabaceae)  Generally grown as cover crops and attractive to many beneficials. Plants in this family include: alfalfa (Medicago sativa); fava bean (Vicia fava); hairy vetch (Vicia villosa); and sweet clover (Melilotus spp.).
  • Mustard Family (Brassicaceae)  Attractive to beneficials that are parasites and predators of the insect pests of the mustard family (broccoli, Brussels sprouts, cabbage, cauliflower, kohlrabi, mustard greens). Be sure to plant these away from the garden rather than in the garden since these plants attract pests as well as beneficials. Some are common weeds, such as yellow rocket and wild mustard. Plants in this family include: basket-of-gold alyssum (Aurinia saxatilis); mustards (Brassica spp.); sweet alyssum (Lobularia maritima); yellow rocket (Barbarea vulgaris); and wild mustard (Brassica kaber).
  • Verbena Family (Verbenaceae)  Attractive to a variety of beneficial insects. Many plants in this family are favorite garden flowers. They include: lantana (Lantana camera); Buenos Aires verbena (Verbena bonariensis); hybrid verbena (Verbena x hybrida); and lilac vervain (Verbena rigida).

Beneficial insects also need a source of water. Shallow containers such as ceramic pot saucers with pebbles for the beneficials to rest on are best.

Suggested OSU Extension publications:

PNW550: Encouraging Beneficials in Your Garden

For kids:

EC1601: The Wildlife Garden: Dragonfly

EC1604: The Wildlife Garden: Lady Beetle

EC1605: The Wildlife Garden: Praying Mantis

Suggested websites:

National Pesticide Information Center, Beneficial Insects.

Penn State Extension, Attracting Beneficial Insects

Sick plants? Get the most out of Master Gardener Plant Clinic!

By Elizabeth Records, Master Gardener Program Assistant

Previously published in Growing.
 

Three gardeners standing at info booth.
Master Gardeners are here to help at Pop up Plant Clinics in a location near you.

It’s gardening season! Whether you’re a longtime gardener or are new to growing things, OSU Extension Master Gardener Volunteers are here to help you grow your best garden yet and deal with garden challenges.

Master Gardeners are volunteers who complete a specialized training program and work as a team to help find solutions to garden problems for people in our community. We are from all walks of life and have widely varied gardening interests and experiences. Together we bring lifetimes of collective garden knowledge to solving plant problems with research-based information. Here are some scenarios where Master Gardener volunteers can help:

Plant Identification

You are digging in the garden and find an unfamiliar plant that you did not put there. Will it produce lovely flowers or tasty food? Or will it prove to be an invasive weed that takes over your garden? Master Gardener volunteers can help you find out. Bring a sample of your plant including a full branch or stem with any leaves, flowers and fruits that may be present.

Insect issues

You find a mystery insect in the garden and wonder if it is going to harm your plants or be a helpful pollinator or a useful predator of insect pests. A dozen insects appear in your garage, and you don’t know if they are a simple nuisance or are likely to feed on you, your pets or your home. Master Gardeners can help identify insects and suggest how to manage them! Bring the insect in a sealed jar, or a high resolution photo of the insect on a pale colored background, next to a ruler or coin so we can tell the size.

Gardening guidance

Just starting your first veggie garden and wondering when to plant, or what varieties do well in your location? Want to make your garden more sustainable by using less water, attracting more pollinators or using fewer chemicals? Short on space but excited to grow fresh herbs or salads on your windowsill? Whatever your gardening goals, Master Gardeners can help you find research-based information to get the most from your garden.

Diagnosis and recommendations          

Your previously healthy plant suddenly wilts. Brown spots appear in your grass. A tree that produced lots of fruit in the past stops setting fruit. Master Gardener volunteers can help figure out what is going on and decide what to do next for best results. Bring samples and/or photos that show the problem and also the surrounding area.

Get the most out of plant clinic
  • Be ready to answer questions that will help Master Gardeners hone in on the source of your problem so we can provide the best advice possible. Master Gardeners might ask, “how long has this problem been going on?” and “Are all of the similar plants affected, or just one?” “What treatments have already been attempted to remedy this situation?”
  • Bring good samples – you can always call us for suggestions to bring the most helpful samples.
  • Master Gardeners cannot answer questions about State or Federally controlled plants, identify mushrooms, or offer medical advice. We are pleased to assist with all your other garden questions to the best of our ability.
  • Sometimes we may need input from other team members or horticulture faculty to resolve your question. Be ready to share an email or phone number if we need to do some extra research and follow up.
  • Have fun and enjoy your garden, even when things don’t go as you expected!
Plant Clinics near you!

Find us at your local office most weekdays from 9-12 and 1-4. Email or leave a phone message anytime.

Benton County

  • 4077 SW Research Way, Corvallis, OR97333
  • Call with your question: (541) 766-6750
  • Email your question and any photos to: bentonmg@oregonstate.edu

Linn County

Do you have fruit trees? Tips on codling moth management from MG Alan Taylor

Alan Taylor has been a Benton County OSU Extension Master Gardener since 2015. When he’s not growing grapes and fruit, Alan puts his scientific background to use at the Master Gardener plant clinic by helping communities, teaching new volunteers and troubleshooting equipment.

If you have ever bitten into an apple and gotten a taste of a worm, there is a good chance it was the larva of a codling moth, a major pest of apples in the Pacific Northwest. Read on to see how Alan uses the data to get ahead of codling moths– and how you can, too!

biofix (plural biofixes)
(biology, pest management) A biological event or indicator of a developmental event, usually in the life of an insect pest, that initiates the beginning of growing-degree-day calculations.

Codling moth larva exiting fruit to pupate (Washington State University – E. Beers, July 2007)

For codling moth, this is the first date of consistent capture of adult moths in pheromone traps, and this year the consensus date for the mid-Valley biofix appears to be 29 April.

Now the fun part: CLICK HERE to visit the IPPC codling moth model (Brunner and Hoyt).

This link to the degree-day model gives a map to let the user select the weather station, and the correct biological model has already been selected. The user will need to enter the biofix date (I’ve been using 29 April) and then the calculations will give the appropriate dates for spraying.

For example, I clocked on a weather station in SW Corvallis, then entered 4/29 as starting date. This gives 20% hatch at 6 June and 50% hatch at 18 June. These two dates are the timing of the two sprays of insecticide for the first generation of codling moth.

Then I selected a site NW of Corvallis with an elevation of 780’, more representative of where I live (unfortunately no good sites both to the SW and at elevation are shown in the map), and the prediction is 20% hatch on 11 June and 50% hatch on 23 June. You can see the effect of a cooler location or microclimate. I have consistently noted that bloom and ripening of my fruit (apples, pears, grapes, etc.) is 7 – 10 later than that of friends down in Corvallis. Being at ~700’ and somewhat closer to the coast does make a difference, and I’ll be allowing for that in my sprays this year. Realistically, this is a conservative estimate, because I should also have a later biofix at my site, but I’ve chosen to ignore this. Last year, I used the timing for the Valley sites, and my apples were very clean.

Just to complicate things, not all insecticides remain effective for 12 days. I think spinosad, which I used, is supposed to be good for 10 days. Always compromises, so I used the model timing of the first spray, then waited 10 days for the second spray.

Finally, there are 2 and sometimes 3 generations of codling moth in the Valley. I’ll use the model to predict the spray timing for the second generation (we can cover that later), and I chose to ignore the potential 3rd generation last year. Four sprays is enough!

Read more about codling moths and how to manage them in the Pacific Northwest Insect Management Handbook.

“Project Happy Apples: Reducing codling moth damage in backyard orchards” is a free webinar for Master gardeners and home orchardists alike. Watch it HERE.