I have a well established (5yrs old) Elderberry, (Sambucus Nigra Guicho Purple) that appears to have verticillium wilt (leaves wilt and die on branches). Pruning the diseased wood seemed to force the wilt to progress quickly to other branches. Leaving the dead branches slowed the wilt and new growth was appearing seemingly unaffected. Now, neighbouring shrubs, (Sambucus Plumosa Aurea), have a scorched appearance on its leaves as well half of a Chokeberry, (Aronia Autumn Magic) leaves have turned prematurely red and its fruit is withered before it ripens. These shrubs have always been healthy until this Spring when I noticed the sparce and wilted leaves on the Sambucus. In early spring (before I was aware of a problem) I transplanted creeping jenny from around the Sambucus to a location that is in close proximity to a Catalpa tree. Have I just spread this disease to the Catalpa tree, which is susceptible to verticillium wilt? Should I remove and destroy all three shrubs now? How far can this disease spread? Is this disease brought on by drought? We have been unusally dry for the past two growing seasons on Vancouver Island. Any tips on the prevention of the spread of this disease would be greatly appreciated.
Verticillium wilt is a vascular disease which affects the plants ability to transfer moisture. The effects are more drastic during drought periods as the plant is transpiring at a much higher rate than other times of year. Cutting the damage off is best, destroy the damaged wood and do not compost it. The general aid to plants that are affected is: water well and regularly, fertilize well to encourage new growth. I have heard that the idea is to get the plant to outgrow the vert wilt and thereby limit or eliminate the disease... To my knowledge, vert wilt is a soil borne organism but... if you have it in one place in your yard the odds are that it is allready elsewhere in some volume, moving shovels full of soil or plants is probably a negligible risk at this point.
I appreciate your comments and have tried pruning & extra watering but I'm afraid the elder shrub will succumb to this disease. Not much left to salvage. It is a little disheartening to know the rest of my garden is at risk as I have many (30 - 40) trees and shrubs that are susceptible to this disease growing in my 1/2 acre garden. I have been careful to sterilize tools etc and I burned the disease wood. I've been gardening passionately for 7 years and sadly, these shrubs were finally reaching the perfect height for screening/privacy of our city lot. Thanks again for your comments.
