Options growing Calla Lilies
Calla lilies at the Palmer Fairview Park garden
Calla lily flowers at full bloom may be left on the plant until the first hard frost. At that time the flowers have grown into a seed pod and are heavy enough to bend the stem so that the seed pod touches the ground. If complete pollination took place, there are a lot of seeds inside. Put the seed pod in a cool basement until next May. In May put the seed pod in a container and let it soak for a day or two until soft and mushy to the touch. The seeds can then be separated by pressing the seeds through one's fingers. The seeds are big enough and firm enough to be separated. Seeds should be planted at about one inch in fertile ground. Plant about three inches apart. Seeds germinate in about three weeks and should to be watered most days. Seeds kept in shady areas have a better chance of germinating because the ground won’t dry out as quickly. After the leaves are above ground for a week or two, moving the plants to an area with a lot of light is best for growth.
If owners want calla lilies flowers to last at full bloom for the longest period of time, there is a totally different strategy. As soon as a flower is at full bloom, cut off the flower stalk at its base. Place it in a flower vase and enjoy. It will last weeks longer than if it was left on the plant. The only disadvantage is that the flower will eventually shrivel and no seeds will develop.
If the plant is growing in a pot, there is the option of bringing the pot inside after the first hard frost, placing it in a cool basement and letting the soil dry out. Cut off the dead leaves. New leaves may start to grow around January. At that point there are two options. The plant can be ignored until May 15 when it can be taken outside and watered enough to stay moist. The potted plant could be taken to a main floor area and watered when the growth of the leaves started in January. Full or partial sun is best. Water enough so it does not wilt. Plant or put outside around May 15 when there is little chance of frost.
If the plant is growing outside in the ground and not in a pot, there is another option. When the leaves die at the first hard frost, dig way under the plant and remove all of it from the soil. It will be fascinating to see that the roots grow out of the top of the tuber (bulb, is not accurate) and grow around and down into the soil. Take off the leaves and wash the tuber. Washing with a hose or swishing in a bucket of water are options. Let the tubers dry in the sun. When dry, place them right side up on something like a cookie tray. Keep the tubers one deep Do not stack them. Do not cover them. Next year's leaves will start to grow in January if kept in a cool basement. The leaves will be white if there is no light in the basement and will grow several inches by May. At this point the callas will include dry bare tubers with white leaves growing straight up with no roots. It is all good. I have done it for years. When no more frost is expected plant each tuber with or without leaves in rich loose soil. The key to planting the tuber is remembering that the roots grow up first and then around and down. So the tuber has to be deep enough so the roots stay wet until they grow deep enough. Two inches deep is sufficient to place the tuber in the soil. Water the plants, especially in times of little rain. Wilting leaves are obvious.
What about leaving the tubers in the ground forever? Living 75 miles west of NYC in the Lehigh Valley brings mixed results for calla lilies. If we want all of the calla lilies to live from year to year, bring the tubers inside from the first hard frost until May 15. However, I can take you to calla lilies on my property that I have left alone for several years and they are doing fine. Others have died.
In June 2011 I started an experiment. Calla lily seeds were planted in areas which get sun light most of the day. June is really too late to grow decent sized tubers by the time of autumn frosts. As a result the tubers were left in the ground over the winter. The plants did not flower the first year or the second year as of July 6. The results: plants that were from a parent plant with a pure white flower all grew in 2012. Plants that were from a parent with pink flowers did not grow in 2012. There were about 50 of them. What I draw from this little study is some calla lilies can live through a relatively mild winter and some can not.
The calla lilies that are growing at the Palmer Township bike path garden by Fairview Park had pink flowers. The shriveled flowers have already been pinched off so the plant’s energy will be channeled into making the tubers larger. Next year's plants will grow larger. The tubers will be dug up this fall and kept in a cool basement (not an unheated garage). Anyone wanting to be a member of the Palmer Township Beautification Project can be part of the fall project. At the time the calla lilies are dug up, elephant ears and cannas will be dug up and stored in a basement for the winter. Volunteers or groups who need community service credit may contact Dave Carr at firstname.lastname@example.org.