I live in Mississauga, on. It is May.
My snow ball bush appears to be dead. Two years ago it was in full bloom, last year not as full…..now not a leave.
Hope you have an answer for me.
The spring of 2015 has been slow to start, and many people have reported that signs of life in their gardens are later this year than in other years. The recent warm weather seems to have kick-started most of the tardy plants in our gardens, so it may be worth keeping a close eye on your Viburnum for a little longer, and perhaps you will see flower buds swelling (Viburnums bloom on buds formed the previous season).
From your description, though, it seems that your Snowball (Viburnum plicatum) may have been under stress for a couple of years now, and there are a variety of reasons this may be the case. In the GTA we have had tough winters recently that have seen the demise of many plants, and difficult winter conditions may be the reason for the gradual weakening and decline of your Snowball. Some cultivars are less cold hardy than others.
In general, most viburnums are relatively pest-free, but occasionally disease or insect pest problems do occur, and usually this happens during times that the plants are under stress or growing in less than ideal conditions. It is possible that your Snowball may have experienced one of the fungal diseases this plant family is susceptible to, and this may not have been apparent to you.
If your Snowball continues to show no sign of life, you may wish to take a look at some other options that are available to replace it. The Toronto Master Gardeners Guide to shrubs for various light conditions has lots of good suggestions:
Here is another site that offers suggestions for a shady location: https://www.birdsandblooms.com/gardening/shade-gardening/top-10-shrubs-for-shade/
Snowball Viburnums grow well in full sun to part shade. They prefer moist, well-drained soil and have less tolerance for heavy, clay, or poorly drained conditions.
If you do plant a new shrub, you may be interested in this fact sheet prepared by Toronto Master Gardeners in partnership with the City of Toronto. It contains useful information on how to improve your soil organically for the greatest success in giving your new plants a good start and an optimal growing environment: https://torontomastergardeners.ca/wp-content/uploads/2012/07/Improving-Your-Soil-Organically.pdf