If it's underneath the leaf, have you inspected the patches properly. Is it like a powdery coating, or actually small spots. Either way, if it's powdery, the plant could be suffering from dry conditions, and poor air circulation. Make sure it's mulched well in spring time and not crowded by other nearby plants. Stressed plants can also come under attack, and your shrub leaves may have scale insects. Check them properly. If so, you could treat with pyrethrum.
Hello again, here is a photograph of the underside of one of the infected leaves on my pieris ('forest flame' variety). As you can see there are lots of raised powdery white deposits and also smaller green 'things' as well. Please can you tell me what this problem is and, more importantly, how to successfully treat it.
Thanks for the detailed pictures. They do look like a kind scale infestation. Possibly cushion scale. There are many sprays available and the Pyrethrin sprays I recommended can be used, but you will probably need to spray again, and it's possible that if you have the energy, you could try to remove them by wiping them off yourself. The sprays don't always remove them off the leaves. So don't expect the sprays to always remove them off. Do this, and I think the darkest hours will fade...
Posts
If it's underneath the leaf, have you inspected the patches properly. Is it like a powdery coating, or actually small spots. Either way, if it's powdery, the plant could be suffering from dry conditions, and poor air circulation. Make sure it's mulched well in spring time and not crowded by other nearby plants. Stressed plants can also come under attack, and your shrub leaves may have scale insects. Check them properly. If so, you could treat with pyrethrum.
Hello again, here is a photograph of the underside of one of the infected leaves on my pieris ('forest flame' variety). As you can see there are lots of raised powdery white deposits and also smaller green 'things' as well. Please can you tell me what this problem is and, more importantly, how to successfully treat it.
Thank you for your help in this our darkest hour.
Kind Regards and thank you again.
Arthur.
Thanks for the detailed pictures. They do look like a kind scale infestation. Possibly cushion scale. There are many sprays available and the Pyrethrin sprays I recommended can be used, but you will probably need to spray again, and it's possible that if you have the energy, you could try to remove them by wiping them off yourself. The sprays don't always remove them off the leaves. So don't expect the sprays to always remove them off. Do this, and I think the darkest hours will fade...