I planted an eastern redbud (Cercis canadensis) 3 years ago in the spring, and it doesn't seem to be doing well - it barely bloomed and it's lower branches have few to no leaves.
- it's on the south facing side of the building, but under the canopy of a large tree, so it's fairly shady.
- it was pretty dry it's first two years, so perhaps didn't get enough water, but it rained a ton this year, and I recently increased the irrigation on it to 4+ gal every 10 days. (I redid the drip line so more was upslope)
- I've did compost dressing in Feb, some slow release fertilizer a bit later, and some seaweed fertlizer every month since then.
I'm in Oakland, CA (zone 9b)