Vinca Minor (Periwinkle) ground cover failing to thrive - Ask Extension
We have several rows of bushes, one lilacs and one cotoneasters, with vinca minor (and some vinca major) underneath. For years (decades) it was doing ...
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Vinca Minor (Periwinkle) ground cover failing to thrive #923749
Asked January 18, 2026, 6:00 PM EST
We have several rows of bushes, one lilacs and one cotoneasters, with vinca minor (and some vinca major) underneath. For years (decades) it was doing great, thick cover over the ground under all the bushes. The last few years, it has mostly died out in the furthest reaches under the bushes, but is still healthy at the edges next to the lawn. I've blamed it on the fact that for several years, I didn't really clean out the leaves under the bushes each fall. So maybe it kind of got smothered. Is that a likely problem? The last few years, I've been cleaning that out and making sure the sprinkler reaches back under the bushes, but it hasn't really regrown. Any suggestions?
(Thanks for being there. This office is a great resource!)
Boulder County Colorado
Expert Response
There are several possible issues you may be facing. There could be a progressive disease vector. There may be a pest population that has encroached (thrips at my place). There may not be enough light (photosynthesis). The soil may be short of nutrients.
So, when growth resumes this spring, send us a photo. Look for pests/insects. You can also bring in a sample of the plant(s) for our Boulder county Dx (diagnostic) team to examine.
The CSU Boulder County Extension office is located at 9595 Nelson Road, Longmont, CO. Call<personal data hidden> for current public hours of operation.
Also, you might consider getting a soils test.
https://agsci.colostate.edu/soiltestinglab/
https://agsci.colostate.edu/soiltestinglab/wp-content/uploads/sites/98/2021/12/soil-sampling-instructions-accessible.pdf
The nice part about the CSU soils test is that it provides a list of what you need to do to achieve a desired soil composition.
You mentioned "smothered." This (oxygen deprivation) is also a possibility that can result from soil compaction and/or from over watering.
So, when growth resumes this spring, send us a photo. Look for pests/insects. You can also bring in a sample of the plant(s) for our Boulder county Dx (diagnostic) team to examine.
The CSU Boulder County Extension office is located at 9595 Nelson Road, Longmont, CO. Call<personal data hidden> for current public hours of operation.
Also, you might consider getting a soils test.
https://agsci.colostate.edu/soiltestinglab/
https://agsci.colostate.edu/soiltestinglab/wp-content/uploads/sites/98/2021/12/soil-sampling-instructions-accessible.pdf
The nice part about the CSU soils test is that it provides a list of what you need to do to achieve a desired soil composition.
You mentioned "smothered." This (oxygen deprivation) is also a possibility that can result from soil compaction and/or from over watering.
