Pieris Japonica

miculaediela

I've got 2 pieris japonica within 2 m of each other, it looks like one died over the winter, the other one started to have white spots on leaves, and some dry leaves (from the base upwards); I have started to cut affected branches, and applied some Bayer insecticide and antifungal, although I hate using chemicals, but I absolutely love the Pieris, is quite mature. Any ideas of what the problem is and how to tackle it?

Borderline

The picture of the leaf close up does not show obvious issues that would cause your shrub to die. Perhaps, you can photograph another leaf with more advance damage. It could be the early signs of a Lace bug infestation, but looking at your second photo, it seems to me your shrub is closing down with the leaves drooping, curling and drying up.

The only thing I can think of right now is your shrubs had been affected by the hot dry summer. Evergreen shrubs, especially more mature shrubs don't show signs for a long while and it is possible, your shrubs have been struggling throughout last year and only showing signs now. If that is a case, there is not much you can do right now. I hope I'm wrong. Hopefully others may offer more advice soon.

Papi Jo

I once lost a pieris to the infamous andromeda lace bug. Check https://en.m.wikipedia.org/wiki/Stephanitis_takeyai

miculaediela

Thanks both. On reflection I think there are 2 separate problems - the pieris on the last picture is soothing down, whilst the other one has some insect problem at least on the bottom leaves. Shall I try to hard prune down to the ground the "dead" one, hoping if there is any life left in it it may come back?

Borderline

It's a hard one really. I'm more cautious and would most likely reduce some of the branches back and see what happens. Check it again around mid April, and if no sign of life, then prune right down. 

Stressed plants are a magnet for all sorts of pest and diseases. It would seem that both your shrubs had similar growing conditions. I think it's water and heat stress based on how mature your shrubs are, and how long you have had them, it's unlikely it is grown in an unsuitable spot.

If you can dig in lots of new compost or bark chip to cover the base and keep on top of watering this year, they may rejuvenate eventually, especially the one that still looks well with a few lower leaves showing signs of possible Lace Bug infestation. Prune off the affected leaves and see how it goes.