Jonna is right. They do germinate irregularly. I have learned take out the seedlings that sprout and just let the rest sit.
One way I found to get them to germinate faster is to put them outside and let the rain water germinate them. I usually start them indoors in the spring keeping the soil must barely moist and when I know rain is coming I put them outside. After they get a good rain, I bring back inside.
They definitely don't like to have wet feet or a lot of water. Once the crowns and roots are established though I have found them to be a somewhat tough plant.
They do not like excessive heat. Mine all went into a summer dormancy with the excessive heat and drought here this year. Though they were going to be gonners, but just let the pots sit and as soon as the temps cooled a bit, they all grew back again and I have pots of them now.
