I understand that heuchera is a good choice for a shade, moist location in Toronto. I am looking for the brightest red foliage available and have found fire alarm and fire chief. Do have other or better suggestions?
Heuchera is generally described as drought tolerant, thriving best in moist, well-drained soil, and tolerating conditions from partial shade to full sun. Your location’s drainage, especially in the winter months, and whether your shady conditions are deep or partial, would likely be the key to whether Heuchera would thrive. If this is the burst of colour that you are desire, and your moist location is well-drained, you could certainly give them a try, making sure that your soil is well-amended with organic material to give them good nourishment.
It is sadly not so easy to find perennials with the clear red foliage you are looking for. The Toronto Master Gardeners’ Guide to Perennials for Shade has a good list of plants for moist areas, here. If you were open to moving to the burgundy/purple end of the spectrum, you could consider plants such as Lobelia cardinalis “Black Truffle”, Sedum “Purple Emperor”, or Astilbe “Red Sentinel”. If you were open to annuals rather than perennials,there are some spectacular varieties of Coleus in those vibrant reds.