Compost bins can be an attractive place for flies to lay their eggs. File photoOSU Extension Service
Gardening season is underway, and you may have questions. For answers, turn to Ask an Expert, an online question-and-answer tool from Oregon State University’s Extension Service. OSU Extension faculty and Master Gardeners reply to queries within two business days, usually less. To ask a question, simply go to the OSU Extension website, type it in, and include the county where you live. Here are some questions asked by other gardeners. What’s yours?
Q: I have a compost tumbler (about 40 gallon) that I’ve been filling with kitchen scraps (uncooked vegetable and fruit scraps, tea leaves and coffee grounds only), yard trimmings and shredded paper for about six months now. It is about half full. I have been turning the tumbler whenever I add new material.
Over the last month or two, there have been a lot of tiny flies (like fruit flies) swarming around the compost to the degree that I wear a mask when I open it to avoid them flying in my face. I understand that flies are there to help break down the materials, but this seems like an awful lot and I was wondering if I am doing something wrong.
I stopped adding materials to it, hoping that the flies would run out of food and die, but they are still in and around the tumbler. What can I try to reduce the flies? I’m trying to get my family on board with home composting, but the flies gross them out! – Jackson County
A: I can assure you that you are doing nothing wrong. If your tumbler is anything like mine, it has screened air vents somewhere, and these small flies are entering there.
Because food waste is full of water and calories, and the eggs/larvae are sheltered in the tumbler and its contents, it’s an ideal location for egg laying from a fly perspective.
I’m only guessing, but I wonder whether you have enough dry matter in your tumbler. I fill mine about 2/3 full with autumn leaves, straw, shredded paper before I begin adding kitchen scraps. You mentioned shredded paper, which is good, but it does tend to break down rapidly, due to the heat, pressure and acids in the paper-making process – pre-digested, sort of. You should be able to see more dry materials than food scraps in your tumbler. This won’t eliminate the fly issue – there will always be flies – but it should help reduce their numbers. – Linda Brewer, OSU Extension senior faculty research assistant
Sumac tree leaves in the fall. File photo. (Cory Morse | MLive.com)
Q: Our neighbor’s sumac grows a few feet from the fence that divides our properties. The roots grow under the fence into our garden and send up sprouts in our marionberries and blueberries. What suggestions can you give to prevent this? – Lane County
A: Some varieties of sumac are considered invasive because, as seen in your yard, they produce innumerable seeds and spread by root suckers. Another tree that is highly invasive and looks very similar and is frequently confused with sumacs is tree of heaven. One way to easily tell the difference is that sumac’s leaflets have jaded edges, while tree of heaven’s leaflets edges are smooth. Sumac trees produce reddish, cone-shaped clusters of fuzzy fruits during the summer and fall seasons.
Normal fence line controls will not work with trees that spread as sumacs or tree of heaven do. Seeds will drop from the trees and the suckers will grow under any barrier you might try. Chemical controls usually are not effective alone and could damage and will affect your berry plants. The best way to handle seedlings is by hand pulling them. Small trees or saplings that have spouted from the root system need to be removed, along with as much of the roots as possible. If you can only cut them at ground level, cut them every couple of weeks, which will exhaust their root reserves over time.
There are no easy ways to get rid of invasive plants. It takes times and persistence. – Jan Gano, OSU Extension Master Gardener
What's up with this fig tree?OSU Extension Service
Q: Can you tell me what’s wrong with my fig tree? – Lane County
A: Fig trees can be successfully grown in the Willamette Valley, but problems can occur. Figs like full sun, well-drained soil with a pH range between slightly acidic to neutral. There are several factors that could have stressed your fig tree.
How often do you water your fig? Figs are drought-tolerant and once established do not need to be watered often. I notice that you have irrigation on your plant. Have you started to use the irrigation this year? With the higher-than-normal rainfall during May, additional irrigation is most likely not needed, unless it is under the eaves of your house.
Fig trees are not very cold hardy, and the Willamette Valley did see some damage to plants when it experienced a cold period during the late winter to early spring.
How often do you fertilize your fig tree? They do like being fertilized on occasion. The link attached below says “a foliar fertilizer once a month or a balanced (5-5-5) fertilizer in early spring, late spring and summer.” In addition, fertilizer tends to leach out of the soil more easily when a plant is in a container.
If your fig has been in the pot for several years, you might want to think about repotting or finding a place in your garden to plant it. The plant could be root bound and may need it roots trimmed and be repotted or, instead of repotting, allowed to grow naturally in the ground.
Figs can develop a fungal leaf spot. Although there is not much information on it, is has been found in Oregon and noted in an Oregon State University Extension publication: Fig (Ficus carica) - Leaf Spots
In the container with the fig are other pots and plants (or perhaps weeds?) that should be removed as to not compete with the fig plant. Instead, place mulch around the tree to help retain even amounts of moisture available to the fig’s roots.
For more information on fig tree growing see, Don’t Be Fooled, Figs Grow Fine In Western Oregon – Jan Gano, OSU Extension Master Gardener
What can be done about this dying hedge?OSU Extension Service
Q: I have a hedgerow of arborvitae that’s about 40 years old. Some of the plants are dead and probably not revivable. But others are just showing signs of browning. Is there anything I can do to revive them? They’ve never been fertilized. – Marion County
A: Many of our landscape plantings have been very stressed by recent weather events. The heat dome event last summer was especially bad. Many of our conifers are now showing stress and dieback.
The plants in the first photo look like they have been dead for a while. When you bend the branches do they flex or snap? Snapping indicates that the tissue is dead. Generally, there’s not a whole lot that can be done besides give the plants TLC.
It looks like you have at least one irrigation line. Double check to make sure that is functional. Also check the output and make sure that the root zone is receiving even and adequate moisture in the summer months.
Do you fertilize your grass or the nearby beds? If so, then there may already be adequate nutrient levels. It may be worth getting a soil test to determine if fertilizer is needed. Also note that a fertilizer application won’t help the dead areas grow back but could green up the existing foliage if the plant is deficient. – Brooke Edmunds, OSU Extension horticulturist
Indigo flower starts may have transplant shock. OSU Extension Service
Q: I just transplanted some healthy indigo, sunflower and marigold plants on Friday and by the next Wednesday some of the plants are completely white. The indigo is white, the sunflower leaves turned brown. All plants seem to have some discoloration but some are much worse off. We added liquid nitrogen when we watered them in. Do have any ideas? – Lane County
A: From your information and the pictures, I would say transplant shock on the white plant and the sunflower. I say that because they are both recovering. There are green leaves appearing. They may have been planted and the roots damaged, not enough water initially, or too much sun (what a rare comment for May).
The brown or dead spots on the large plant can definitely be from lack of water. Water the plants thoroughly. Check to make sure the soil is moist down to your second knuckle when you stick your finger in the soil.
Since it is now getting warmer, providing shade for the plants will help reduce the stress. The fish emulsion was a good call. However, do not over fertilize which would again send the plants into shock.
Water to keep the plants moist and add fish emulsion weekly but cut the dose in half. Fertilize once a week for two weeks and check plant status. They should be well on their way to thriving. Trim off the dead leaves on the white plant. Leave the other alone. – Sheryl Casteen, OSU Extension Master Gardener
Note to readers: if you purchase something through one of our affiliate links we may earn a commission.
Registration on or use of this site constitutes acceptance of our User Agreement, Privacy Policy and Cookie Statement, and Your California Privacy Rights (User Agreement updated 1/1/21. Privacy Policy and Cookie Statement updated 5/1/2021).
© 2022 Advance Local Media LLC. All rights reserved (About Us). The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of Advance Local.
Community Rules apply to all content you upload or otherwise submit to this site.