Not so "red hot"

I have yet to figure out why these Red Hot Poker plants have stopped showing off their beautiful red/orange/yellow colors? They've bloomed like this for the past few years and it's such a disappointment. There are some varieties that bloom green but when I purchased these I made sure to buy the warm-colored variety. The first couple of years these pokers did bloom with more colors. I don't know what's going on. Do you?