Monday, July 11, 2011
Garden Easter Lily
McClure & Zimmerman, a reputable mail order plant dealer, lists L. longiflorum as hardy to zone 7. We knew that the Easter Lily needed a warm weather location to grow outside but decided to try and grow them here in zone 4. Three zone steps corresponds to a 30 degree F temperature difference but our last two winters have been mild. Last winter the snow cover came early and stayed late. Under this continuous insulation blanket, warmth from the earth found the surface and melted the frost that had penetrated garden soil. Continuous snow cover is not characteristic of our winters so long term our lilies are at risk.
This fall we plan to pot up our bulbs in preparation for winter. Lily pots will be placed in the ground near the south facing house wall. Sunlight reflected off of the house wall and interior warmth that sneaks through the foundation wall should create a zone 5 like micro climate. I can shovel snow on top of the lilies to try and preserve their snow cover. Thus protected the lilies will likely survive the winter.
The real risk comes during the transition from winter to spring. During this wildly changeable time we can have 70 degree F. days followed by 20 degree F. nights. Our plant losses occur during this period of time. This is where having the bulbs in pots gives us options. Pots can be lifted and placed inside the house for protection from cold nights. Weather permitting the pots can go back outside to continue their early season growth. When the weather has settled, tender plants are removed from their pots and placed in the garden.
We plan to force a pot or two by bringing the frozen bulbs into the house around Christmas. A waking up period in a cold basement corner will be followed by a move to the living room. Who knows we may have flowers for Easter.