What perennial or shrub would be suitable for planting with the use of cremation ashes?

Such ashes could be sprinkled around a planting, unless illegal as in some states. In this case they could be used as fertilizer, similar to bone meal. The latter often has an analysis of around 1-13-0, meaning it provides a little nitrogen, but mainly phosphorus, plus some calcium. Buried in the soil at planting, this can serve as a slow-release phosphorus source. However, if planting bulbs or small plants or perennials, you might also add some crushed shells or sharp pebbles to deter digging mammals attracted to the bone smell. Since small amounts shouldn't affect soil pH or provide excessive nutrients, most plants should be amenable, the choice depending more on personal preference, light, and other site conditions.  more