Hi:

You MUST leave the stalks and leaves on (until they go brown and dry up), they replenish the bulbs. I cut mine down late in the fall. However, it is a good idea to cut off the dead flowers / seedpods so they do not rob the bulb of energy.

Cheers,
MG

PS What lily cultivars were you able to procure from Costco? Just curious if it differs between geographical regions.

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