Western redbud doesn't flower
I bought my western redbud three years ago in a one-gallon pot and planted it in a somewhat shady corner of my yard in Marysville. It has lousy drainage (lousy enough that the golden poppies at its feet tend to be chlorotic), but not quite as lousy of drainage as the rest of the yard (meaning that the golden poppies do manage to survive in that corner, and there isn't standing water puddling on top of the mud in that corner). It seems reasonably healthy; it's grown to five and a half feet tall now. However, it's never produced a single flower. Just like last year and the year before, it's been leafing out this year without producing any hint of flower buds.
I've heard that redbuds don't flower in many places near the coast, due to inadequate winter chill. But this is the eastern edge of the Sacramento Valley, and there are redbuds growing wild just down the street from me that flower just fine. So what do you think is the issue with mine? Is it in too much shade? Is it unhappy because of the poor drainage? Is it a genetic strain from some other part of California that needs more winter chill than the ones native to this area need?