I have two arborvitae that had bagworms last year. I would like to treat them this spring but have four rose bushes (David Austin English roses) in very close proximity. Will the bagworm sprays harm the rose bushes?

Thank you.

HI Tracy, first the correct time to spray with BT products for bagworms is in late June to early July (this year it may be mid June to late June) when the bagworm caterpillars are small. systemic insecticides are not effective on bagworms and spraying other than when the caterpillars are small is also not effective. and no the sprays will not harm your roses. hope this helps, sandy