Where do you have them siting- full sun, part sun?
How wet are you keeping them?
What kind do you have?

My experience with the Princess Lilies is that they prefer full sun and don't like to be overly wet.

Shelley

They are in full sun, but we've had a lot of rain, but the pots have holes at the bottom so they are not sitting in water. Can't remember the name, got from Botanus, dark pink

Mine have been acting a bit temperamental and are slow this year, too. My new 'Isabella' pots are just budding and my poor 'Sara' pots are just now settling in and deciding to grow. They have no signs of bloom yet. Way, way behind from the last couple of years. But, they will yet put on a good show - just a shorter one. Last week, much of the greenery was turning yellow from this damp spring weather. My pots have very good drainage, too, but it has just not been warm or dry enough for them yet. All I can suggest is patience. Might just not be the year of the alstromeria.

Shauna

Mine are looking sad too, but I can't really blame the weather. I didn't get the very crowded pot I bought split and replanted quickly enough, then our puppy decided to dig one out so he could play with the pot. I rescued it and replanted, it died, and I put petunias in the pot. Now it looks like I have a fresh shoot poking out, so I have hopes yet!
Connie