Richmond Hill Ontario..clay type soil,plant bloomed throughout summer 2018 but appears lifeless so far in spring 2019
Your Hibiscus moscheutos ‘Luna Rose’ is a wonderful perennial for sunny, moist gardens. It will attract hummingbirds and pollinators with its gorgeous mid- to late-summer flowers. Based on the photo provided, the plant looks like it performed well last year.
The GTA has had a cooler than average Spring and it is not surprising you have yet to see any growth indicators. Once the ground temperature begins to warm, you should start to see emerging new growth, presuming the plant survived the winter. The plant zone for perennial Hibiscus is Zone 5-9, which should be fine for your Richmond Hill location Perennial when we have a particularly harsh winter, the cold can affect plants which are on their edge of hardiness zone.
Unless you have examined the root ball and it is complete “mush”, which would mean it has not survived the winter, don’t give up!
https://www.torontomastergardeners.ca/perennials-for-full-sun/