Bushes suddenly dying - Ask Extension
As I wrote to your office a month ago (but did not attach photos), and you kindly replied right then and there, two of the six azalea bushes in front ...
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Bushes suddenly dying #214433
Asked September 26, 2014, 4:31 PM EDT
As I wrote to your office a month ago (but did not attach photos), and you kindly replied right then and there, two of the six azalea bushes in front of my town-house have died suddenly in two last month after 10 years of growing well. I took the dead azaleas out and trashed. Also two hardy and tall cherry laurel bushes immediately next to the concrete steps to the front door of my town house have been dying since last July. During last six weeks, as a gardener advised, I started to apply to the soil around the dying laurel bushes a concentrate (Mono-- and Di-potassium, Salts of Phosphorous Acid) but it did not help. A gardener also advised me to take off dead leaves from the branches and rake off dead fallen down leaves from the ground around the bush.
I am attaching photos of the bushes as they are now
I am attaching photos of the bushes as they are now
Montgomery County Maryland
Expert Response
From the photos it looks like the shrubs may be subject to some type of root problem. Since your azaleas died back in this area and the cherry laurels are declining, you may want to test the soil in these areas. Results will give pH and nutrient deficiencies. https://extension.umd.edu/hgic/soils/soil-testing
Cherry laurels in general grow best in a well drained soil in morning sun and afternoon shade. Has something changed in the area such as drainage, downspouts? They will not be happy in a poorly drained soil and can be susceptible to roots rots. Check the drainage in the area.
Make sure the shrubs are not planted too deeply as they can be susceptible to boring insects. These insects are also attracted to thick mulch. Keep mulch no thicker than two inches and away from the base of the stems. Look around the base of the stems for holes and frass.
Cherry laurels are also prone to scale insects such as the white prunicola scale. This is a sucking insect that can cause dieback. Monitor for these scale insects - look along the branches and stems for small disc or oystershell shapes that can be scraped off. See our website http://extension.umd.edu/learn/armored-and-soft-scales-trees-and-shrubs
It may be helpful to call and speak to a horticulture consultant M-F from 8-1 at <personal data hidden> for more information.
mh
Cherry laurels in general grow best in a well drained soil in morning sun and afternoon shade. Has something changed in the area such as drainage, downspouts? They will not be happy in a poorly drained soil and can be susceptible to roots rots. Check the drainage in the area.
Make sure the shrubs are not planted too deeply as they can be susceptible to boring insects. These insects are also attracted to thick mulch. Keep mulch no thicker than two inches and away from the base of the stems. Look around the base of the stems for holes and frass.
Cherry laurels are also prone to scale insects such as the white prunicola scale. This is a sucking insect that can cause dieback. Monitor for these scale insects - look along the branches and stems for small disc or oystershell shapes that can be scraped off. See our website http://extension.umd.edu/learn/armored-and-soft-scales-trees-and-shrubs
It may be helpful to call and speak to a horticulture consultant M-F from 8-1 at <personal data hidden> for more information.
mh
