Hi there, I was planning to get rid of a yew next year because it has an ungainly shape when I discovered it has a terrible infestation of mealy bugs. I started to treat the infestation with water sprays and safer soap but I now I am thinking that I might as well get rid of it. I wanted to replace it with another shrub possibly another yew, hydrangea or dogwood. However I know all of these shrubs are susceptible to mealy bugs. I wondering if at this point it is safe to plant another shrub at this site. would the mealy bugs just transfer to the next shrub? Is there anything I can do to prepare the site or do you know of another medium sized shrub for the shade that isn’t susceptible to mealy bugs? Look forward to your reply.
Your proposal to replace your yew with another plant, given the mealybug infestation and its ungainly shape seems to be the right one. Unfortunately there are many kinds of mealy bugs which affect different plants. It may be impossible to completely prevent mealybugs in your garden but you can reduce their impact and mitigate there effects through gardening techniques such as the water sprays and insectical soal that you have tried. As well you should practice integrated pest management techniques in your garden as healthy plants are less susceptible to infestations. In order to reduce the risk that the mealybug already in your garden will simply move to the new shrub I suggest moving the yew and waiting a few weeks before planting another shrub. During that period you should examine the remaining plants in your garden for mealybugs and treat them before planting the new shrub. As well, you should carefully examine the replacement shrub to ensure that it does not have mealybugs when you bring it into your garden, as greenhouses and nurseries are very common breeding grounds for this pest.
I suggest that you chose some shade tolerant shrubs and then ask your local garden centre which species and cultivars are mealybug resistant.
Here are links to information on the Missouri Botanical Garden website in mealybug control outdoors and to the Toronto Master Gardeners Guides on Ornamental Shrubs for various light conditions which contains useful information shrubs which can be chosen to grow in shady conditions and to Integrated Pest Managment techniques.