Many agricultural plants that are reproduced by vegetative division face a mysterious problem that results in a decline in the clone vigor, and most farmers and nurserymen claim that the plant crop has “run out.” A number of factors adversely affect the plant clone to the point that it becomes unproductive and uneconomical to continue growing.

A technique has been discovered that has revitalized the agricultural crops such as strawberry, raspberry, blackberry, sweet potato, banana, and a newcomer: the canna lily. This flower bulb or rhizome is facing present and future disastrous consequences unless governmental regulatory steps are taken to correct the dilemma facing the canna lily industry. Since the 1940s, canna lily rhizomes have been continuously commercially grown from the original stock that could easily be harvested in the fall, packaged and resold by Dutch mailorder companies (few exist today, most went bankrupt) as named varieties. Commerce developed so extensively around the success of selling millions of these rhizomes that some farmers began to cultivate canna lilies in fields, planted in rows like corn, exclusively for the Dutch mailorder companies. For some canna growers in the states of Arkansas, Oklahoma, and Texas, the financial rewards were so excessive, that they began to plant hundreds of acres as an exclusive agricultural crop. Because of a shift in business retailers a decade ago, when the canna lily sales were shifted away from packaged rhizomes of mailorder companies to the potted, growing, blooming canna lilies for spring and summer sales by boxstores such as Walmart, Lowes, and Home Depot. The boxstores bought their potted products mainly from contracted nursery growers, purchased as dormant, canna lily rhizomes from the exclusive field grown canna farmers who originally supplied the mailorder companies just a decade ago. This dramatic change from selling dormant canna lily bulbs to trusting mailorder customers to the customers at box stores, who observed the plant flowers and leaves before purchasing, has made it necessary for box stores to reject many of the inferior potted canna lilies, that had over the years declined (run out) to a state of unpredictability. This rejection had not occurred to mailorder customers who were buying an unseen, untested rhizome with a “wish” that it grow into that beautifully-pictured dormant plant that was packaged for sale in the mailorder catalog.

Growing canna lilies for retail sale has now become a crisis much like the one that threatened the growers of strawberry plants, raspberry bushes, blackberry bushes, and banana trees years ago.

The canna commercial growers proceeded each year to set aside part of the current canna rhizome crop to use as seed for renewal planting the following season. As growing continued each year, certain genetic defects and susceptibilities began to appear and accumulate and grow more seriously each year. The canna farms continued regrowing and selling more and more diseased and mutated canna rhizomes each year, until they could be viewed with horror in full bloom with the distorted flowers and ratty leaves in contrast to the buyers at the stores and their unhappy retail customers. Many of these canna varieties were originally grown and sold as true to name varieties. After many decades of vegetative reproduction, the canna crop has become a mixture of harmful and inferior mutations susceptible to many diseases, insects, nematodes, and flower abnormalities.

Commercial growers of cannas practiced a technique that they called “roguing” that involved searching through rows of cannas in full bloom and discarding those that appeared to vary visually from the desired variety intended to be grown. This technique only worked partially, because many of the weaknesses and inferior qualities could not be visually determined, such as canna rhizomes that failed to bloom at the time the farmer decided to “rogue” the canna fields. Additionally, the genetic factors that were mutated into the rhizomes that made the plant susceptible to diseases and other impediments would not be seen, since the commercial fields were normally sprayed effectively to remove pests; however, the normal home gardener does not expect to buy a plant that must be continuously sprayed with fungicides, nematode treatments, or for insects, and as soon as their potted plants are placed in the home garden, the leaves are exposed to the assaults of the leaf rollers, and the webworms, and the rhizomes become infested with the ravages of the nematodes. This disenchantment of retail buyers and admirers of cannas is expected to drastically curb the future purchases of canna lilies.

Plant decline in such agricultural products as strawberry plants, raspberry plants, blackberry plants, sweet potato vines, and banana trees has been approached and largely overcome by the process of tissue culture. Plant scientists have discovered that the rapidly growing tip of a plant called the “apical meristem,” can be removed and placed into a tissue growing medium. The plants from which the apical meristems are removed are carefully selected to reproduce and must conform to the original desirable characteristics of the parent cultivar. The apical meristem grows so rapidly that by carefully selecting the few cells at the tip, virus and other mutation problems are left behind to result in a new plant that is vigorous, disease-free, and fast growing.

This group of cells grows into a complete plant with shoots and roots systems intact, that are collectively called “nuclear stock mother plants.” These “mother plants” are used to divide vegetatively from which commercial, private sector nurseries are permitted to sell certified plants to farmers that are free of virus, bacteria, and other diseases.

As of August 1, 2006, no suggestion has been made to restore the canna growing industry from its present chaotic disposition by the use of tissue culture technique. Tissue culture could restore the reputation of marketing and production of canna lily rhizomes to a satisfactory acceptance level of approval by both wholesale and retail customers.