Sarcococca

Question: Sorry, this is the second question. The first one I sent in didn’t include a photo. I have three of these plants and all of them have been dropping leaves. Is there something that I need to do to or for the plants? I live at 1000 feet if that makes any difference.

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied April 19, 2023, 11:53 AM EDT
response: This isn’t our first question recently about Sarcococca leaf loss. Is there disease? Or the plant reaction to this winter’s weather? I hope your plant will leaf out again in the coming weeks. Share a photo from more distance, please. This Ask Extension question about Sarcococca illustrates why seeing the whole growing area is useful for diagnosing a plant issue.

responder: The Question Asker Replied April 19, 2023, 6:38 PM EDT
response: Please let me know if these photos help determine why there is leaf drop. Thanks, Phyllis On Apr 19, 2023, at 8:54 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: Jay W. Pscheidt, PhD, Professor  Replied April 20, 2023, 8:22 AM EDT
response: Your images do show leaf loss of your Sarcococca but I also note that the stems have remained green. No other plants appear to have defoliation in the images. Wet soil can be seen but rather typical for this time of year. There also seems to be a slope to the garden in some places.  The reason for the defoliation is not clear. Root issues are possible but less likely due to topography and green stems. There is a new fungal leaf spot, stem lesion problem called boxwood blight where a dominate symptom is defoliation. This unlikely as it is rarely seen in the landscape and shown susceptible mainly under laboratory conditions.  The more likely problem is abiotic or non-living issue, especially since other reports of the same condition have been coming in. Wet cold weather is unlikely to be the issue since these plants normally can tolerate these conditions and generally flower nicely during the middle of the dormant season (the main reason to put these in  our gardens). We have seen a similar defoliation event occur a few years ago when we had a major smoke event in the Willamette Valley. Sarcococca spp. experienced significant green leaf drop over a few days after the smoke dissipated. These symptoms seen throughout the Willamette Valley where smoke was heavy but not in the Seattle area where smoke was not a problem. Plants in gardens and open-air structures were affected but not in a plastic hoop house. There was less species information but it appears S. confusa and S. ruscifolia were affected but the more common S. hookeriana var humilis were not. https://pnwhandbooks.org/plantdisease/pathogen-articles/nonpathogenic-phenomena/air-pollution-ozone But that was then and during the early fall. I suspect there may have been some air pollution event this past winter to cause these symptoms. An air inversion where wood smoke from heating fires gets caught in the area is one possibility. It would take more investigation of a broader area to figure this out.  Since the stems are still green we suspect the plants will leave out again.

responder: The Question Asker Replied April 20, 2023, 11:40 AM EDT
response: Thank you Jay,Is there any product that you recommend for the plants at this point?Sent from my iPhone On Apr 20, 2023, at 5:22 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: Jay W. Pscheidt, PhD, Professor  Replied April 20, 2023, 11:51 AM EDT
response: No products to recommend. I did, however, ask this question on a Facebook group and got a relevant response back:  "We have a problem in the oregon coast when it is too wet and the soils don’t drain well. I would point to root rot and too much water. The good news is that most of the time I have seen the plants recover. You might loosen the soil around the plant and make sure it’s not sitting in a low area full of water logged soil."

responder: The Question Asker Replied April 20, 2023, 11:58 AM EDT
response: Thank you so much. I really appreciate your help.Sent from my iPhone On Apr 20, 2023, at 8:51 AM, Ask Extension <<personal data hidden>> wrote:﻿