Madonna LIly - planting depth advice needed, help!

I have 3 Madonna Lilies that I just planted (Lilium Candidum). The package said to plant 6 inches deep, but then when I checked another site, said only an inch covering bulb. I searched more - and found about 50% each way - some sites said 5-6 inches, others said only an inch.

What do YOU do?

Note, am in Zone 5.

I would love to know the answer to this too. I have about 13 a nice lady sent me in a trade that need planted.

Davena

The American Horticultural Society A-Z Encyclopedia of Garden Plants says
"Plant L. candidum and L. x testaceum no more than 1 in. deep; they tolerae drier soil than other lilies and require alkiline soil."

It also lists zones 6-9. My guess (only a guess) is that a deeper planting may be appropriate to insulate from the cold in colder climates.

as far as I know all lilies root along the underground parts of their stems which helps stabalise the flowering stem and get more food for the bulb