Answer: Deformed leaves can be a cultural problem, one related to insects such as thrips, or it might be a virus. If thrips are the problem be prepared next season to spray the plants with pyrethrin or neem (an organic control - extract of the neem tree seed). Apply as directed by the product label - you may need to start spraying even before the buds appear.
Viral or mosaic infection can be a problem with all lilies. To avoid it, buy healthy bulbs from reliable sources. (Which you have done.) Dig and destroy any lilies that show mottling in the leaves or seriously stunted growth. Also control aphids, which spread the infection. There is no cure for the virus, once it attacks a lily.
For a positive identification of the problem, you might want to take a sample to your local Extension Service for them to examine. You can reach a helpful diagnostician at (909) 387-2166.
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