As the rhyme to contrary Mary goes….” with silver bells and Cockell shells, and pretty maids all in a row.” But here in the deep south our gardens tend to overgrow where we did not intend, or fill the beds with weeds that we must remove, endure attacks from various predators/ infestations, or fizzle and dry in the intense heat of the summer. Individual plants as well as entire gardens repeatedly demonstrate that the gardener is not the master of horticultural results but merely the caretaker.
Thus it is with the cultivation of the beloved and despised Canna Lily. The heat loving tall, sturdy stalk surrounded in broad, deep green, striped or reddish leaves that support glorious fluffy blossoms of deep red, bright orange or yellow or smallish red blossoms are both admired and hated. If these beauties are happy in their surroundings, they will prosper, multiply and present a bright and colorful display for all to enjoy in the heat of summer, including pollinators. But along with this beauty comes some of nature’s “beasts” of a sort.
The first beast of negativity to present itself in your Canna Lily patch is likely the disfigured, curled leaves with holes that tell you that a Canna Lily Leafroller caterpillar has found a home and a food source in your plant. Your choices are to either remove the damaged leaves, remove each caterpillar, treat with Bacillus thuringiensis kurstaki (BTK) or remove the actual stalk/plant. The plants will need to be monitored throughout the season for continued treatment or removal.
The second negative (or positive, depending on your objective) you may encounter with your Canna Lily is that the bulbs will multiply rapidly resulting in thick stands of these heat loving beauties. If you prefer a less dense grouping, you can either cut the stalk off at the ground and periodically dig up clumps of bulbs to decrease the number of plants. Such thick stands of this plant can block or divert irrigation resulting in areas that are too wet and areas that remain dry. Where the bulbs are allowed to remain in the ground through the winter, plants will begin to return in spring, but seasonal thinning of the bulbs is wise.
The third somewhat negative when growing Canna Lilies will be the deteriorating blooms and determining whether you want to prune those away or not. This pruning can be satisfying and can encourage more blooms, but it is not a requirement. At the end of the season, you can simply cut down the entire stand of Canna Lily stalks, remove them, cover the area with mulch and wait for next season’s growth to peak out in spring. You can also dig and divide the clumps and share with friends or plant in another area.
Recently a small group of dedicated Master Gardener volunteers worked to thin the stands of Canna Lilies in the Southern Garden of Phase I of Montgomery Botanical Gardens by removing individual stalks, digging up large clumps of bulbs and pruning remaining stalks. Lynne Kuhlmann, Tom McLemore, Jane Ficquette, Missy Coker, Suzanne Reaves, and Cathy Maddox accumulated a large pile of garden debris from thinning the Canna Lilies. This now allows the irrigation to reach the Bridal Wreath Spirea and Azaleas behind the lilies. MBG Volunteers are vital to the health and beauty of the gardens. If you are interested in becoming a MBG Volunteer, let us know by emailing us at info@montgomerybotanicalgardens.com.
