Forum home Problem solving

Thuja blight

I've been growing a small thuja conifer trimmed into a ball shape next to my front door for seven or eight years now, it gets a haircut once a year in the spring or early summer and by the end of the year it is starting to look shaggy again. I have noticed that after its haircut which it had about three months ago it hasn't put out any new growth and now looks rather yellow bordering on brown in places. I gave it an inspection for aphids which I have heard can be a problem but couldn't see any so I think that it may be blight. Deep down there appears to be green growth but how long that will last for remains to be seen. All these years with no problems and now this happens and yesterday I spotted what I have found out were large rose sawfly on two bushes in the back garden and that's the first time I have ever come across them, not to mention the powdery mildew on the patio roses and sweet peas, although the zonal geraniums don't seem to be suffering from rust this year and there's no sign of black spot on the rose bush in the front garden and that's a first.


  • barry islandbarry island Posts: 1,667

    Hi Gertie I had a good look at the old woody growth inspecting for aphids and it looked to be clear of them although I believe that they can be hard to spot, the woody growth looked to be sound and there was fresh green growth under the surface yellowing, I didn't notice anything that looked like cobwebs. I will just have to wait to see if it recovers from this, the thing is that it has been there for a good few years now through periods of very wet summers, drought, hard frosts but for some reason it has succumbed this year. I suppose that plants get sick the same as we can and won't live forever.

  • conifers generally show signs of stress or worse impending death way after the event.

    It may something very simple like dryness - beds near to the house are generally quite dry and it may be that.  Give it a real good soaking and liquid feed  

Sign In or Register to comment.