Lilies disappearing?

I have several Oriental lilies and an Orienpet or two. But only my one Asiatic lily came up, and just one of them. What could the problem be?

Critters digging them up or eating them? They are a favorite food in my neighborhood.

Were they just planted this year? I had some newly planted last year, they did not come up, but this year they did and bloomed. So be patient.

I don't think they were dug up because I didn't see any activity there. I did have voles earlier but no sign of them near the lilies. So I am praying that they will be up next spring.

Does the area have good drainage? They can easily rot if the soil stays too soggy.
Pam

Yes, I live on the side of a mountain. Some are in the rock garden and some are in a terrace. All have excellent drainage

I planted some bulbs in the fall of 2003 that didn't appear until this year.

should they be fertilized in the fall?