Denyse Cummins | 7/13/2007 11:02:23 PM
Cut flowers are selected for stem length, vase life and especially for suitability for the climate in which they will be grown. Plant physiology plays a major role in flower initiation. Some flower species require a cold period or vernalization to initiate flowering. Flowers that are used for winter field growing in the United States are not suitable for summer growing because the plant may grow but will not produce flowers without that cold period. For example, stock or freesia cannot be produced in the summer because they require several weeks of temperatures around 56° to initiate bloom. Though given in reference books as summer field cuts in the northern United States, they will only succeed here if fall sown. The opposite consideration, tolerance of high heat and especially high humidity, affects choice of summer cuts. Flowers which may thrive in the low humidity of the western United States may produce poorly here, succumb to fungal diseases or need to be regularly sprayed with fungicide to avoid flower blights or leaf spots. Some species only initiate flowers during lengthening days and can only succeed when spring planted. Flowers which typically bloom in the fall cannot be induced to bloom at any other time in the field, since their flowering cue is shortening day length. Be sure you don’t take up field space with them until mid-summer.
Choose flowers that will grow with a minimum of spraying. Diseases and insect pests may be problematic at some times of the season and not others, affecting when you can plant and expect success with a minimum of spraying. Besides the labor involved in spraying, keep in mind that you and your workers will be handling the flowers intimately and try to keep pesticide exposure to a minimum. Choose flowers that will not have to be staked. Any decrease in labor is an increase in your profits. The layers of net support used in 20-foot-long greenhouse beds can involve a lot of labor and ingenuity in a 75-foot field row.
Cut flowers may be annuals, perennials or bulbs. Perennials are best planted in the fall because many need vernalization to bloom. A very small plant put in place in the fall can emerge in the spring three times larger and ready to bloom well after a winter cold treatment. You may start your own from seed (since availability at that time of year is very limited in the nurseries) or order field-dug dormant materials from northern growers. With sufficient advance notice (up to 12 weeks), many of the cut flower varieties for both perennials and annuals are available as plugs.
Annual seeds can be obtained from numerous seed companies through the mail. A lot of the big off-the-rack seed companies are now beginning to concentrate on cut-flower seeds for the homeowner and can provide a good selection, though quantities available in a grocery store seed packet will never be cost-effective for the grower. A few cut flower plants can be found as transplants at the nurseries, but be sure to note the plant height on the tag. Most available bedding plant varieties are bred for compactness, an undesirable trait for cut flowers. Avoid like the plague varieties labeled 'dwarf.' Rather than purchase flats of bedding plants locally, It’s much cheaper to order plugs.
Variety selection is a matter of experience, which can only be gained in one way -- by variety trials. Some cultivars of a plant are more disease-tolerant or more tolerant of cold, heat and drought or poor drainage than others, but you have to trial as many as possible to find out. There are many more suitable flowers and varieties of flowers than are given in this manual. Any flower with a stem at least 12" long and a vase life longer than four days is a good cut. Get out there and find them.