Annuals

Denyse Cummins  |  9/6/2007 1:03:21 AM

Annual statice is a cool-weather crop that's great as filler or for drying.

Pollenless suflower varieties have the longest vase life.

Annual cut flowers are divided into hardy annuals, which grow through the winter unharmed by freezes, half-hardy annuals, which require cool temperatures but can’t take a hard freeze, and annuals, warm-season plants that produce flowers in the heat of summer.

Fall Planting

Fall-planted annuals all require vernalization (temps under 55) for flower initiation. Fall sowings are best, but flowers of lesser quality can be produced with transplants sown in mid-winter and planted out in very early spring. Spring sowings are also of lesser quality (shorter and less robust) and may have production curtailed by high temperatures in late spring.

Bachelor Buttons (Centaurea cyanus) Direct sow in October. Bachelor buttons make very large plants, so are best grown single-file in the row, 10"-12" apart. Flowers come in the traditional cornflower blue, rose, pink and white. Plants make steady growth of a large rosette through the winter and bloom in February and March. Cut individual stems down as low as possible while still leaving some of the main stem for branching. Good in mixed bunches as a filler.

Larkspur (Consolida ambigua) Direct sow in late October and repeat again in six weeks. Seeds will not germinate unless soil temperatures are cool. Germination can be improved by chilling seed for 7-14 days preplant. Space 6" apart in a double or triple file. Thin to final spacing and manage weeds carefully, as competition will reduce the size of the first, largest stem. Giant Imperials come in dark (Blue Spires) and pale (Blue Bells) blue, rose, pink, and white. The dark Blue Spires is the best; earlier than the pale blue and with less tip die-out (a fungal disease that sometimes attacks larkspurs). The QIS series is also good. Seedlings can be started inside in January and transplanted out, but will be inferior to the fall-sown crop -- shorter and thinner stemmed. The late crop can still be useful for mixed bunches (bouquets). Harvesting begins in late March and continues through April. Cut when the lower quarter to one-third of the flower spike has opened. Cut down low, but not all the way to the ground, because low, smaller side spikes will develop. Larkspurs are worth $6.50 to $7.50 to a florist, but the grower probably won’t receive more than that at a farmers market because it’s not a very well-known cut to the public. Florists love fresh larkspurs. Dry any flowers that don’t sell and sell them later. If you know you’re growing them to dry, let more florets open before cutting. Delphiniums, the perennial cousin to larkspurs, are not perennial here. They can be successful if ordered in as plugs in the fall (seed can be difficult to germinate yourself). Cut using the same rules as larkspur. Larger and less frilly than larkspurs, they are also worth more in the market.

Snapdragon (Antirrhinum majus) Start the tiny seeds inside in September and transplant into the field in about 6-7 weeks, spaced 6"apart. Like the larkspurs, these will sail through the harshest winter field conditions. Begin cutting in late March. The first flower is enormous, worth $.75 apiece. Like the larkspurs, cut low for stem length, but leave several nodes on the plant to produce the smaller side shoots. Some will be big enough to sell in straight florist’s bunches, but most will be smaller and will work fine in mixed bunches. Cut when the lower third of the flowers have opened. The cut stems must be always kept upright or they will bend, due to a geotropic response. Carry your bucket into the field and do not ever lay the stems down. The production of secondary shoots keeps the crop in bloom for over 8 weeks. A spring sowing (February) will bloom in May and have pretty good quality. The hundreds of varieties in catalogs are intended for short-day, low-light winter greenhouse production. The best variety grown in the field is the Rocket strain, which comes in all colors but blue, and all are good. Other non-greenhouse varieties are rarely tall enough for cut flowers. Redstone is a deep, clear red. As the weather warms, watch for fat, green caterpillars that eat the flowers. Control them with Bt or an insecticide like carbaryl.

Stock (Matthiola incana)  Most stock are bred for greenhouse culture, but selecting the right varieties can produce baseball-bat-sized blooms outside. Stocks have a problem in that all varieties except the Cheerful series (yellow or white guaranteed doubles) produce single flowers as well as the desirable doubles. Singles can be used in mixed bouquets but have a short vase life and tend to shed petals. Florists won’t buy them. It is said that it is possible to segregate out the tiny seedling singles by leaf color, but it’s not easy. A few of the best varieties are Nordic Crimson (really a rose color), Pacific Crimson and the Cheerful White and Yellow (guaranteed 95% double). Non-branching Apricot is pretty good, too. Stock will not tolerate poor drainage. In a year with a lot of hard freezes, they will all be lost, but in a mild winter, there is nothing as wonderful as these big, immensely fragrant cuts. They’re worth $6.50 or more per bunch. They are the first of the winter crops to bloom. Start seedlings inside around the first of October to have them in production for Valentine’s Day. Space 4" apart. A spring sowing is not usually worth the trouble because stocks require a long cold period to initiate flowers, don’t take heat well and will produce short, unsaleable flowers in warm weather. To harvest, pull up the entire plant, roots and all, and then wash all the dirt off the roots in a big bucket of water at the end of the row. Sell them with the roots on.

Sweet Peas (Lathyrus odoratus) Select a variety specified for cut flowers; the stems on garden varieties are too short to work with. Plant in October or November and provide a good trellis. They’ll bloom in February or March and continue into May. Snap them out of the leaf node rather than cutting, or sacrifice some of the plant to gain additional stem length. Do not let any old flowers to go to seed, since this will stop production. Watch out for aphids, which feed on new growth at the tips. Stems are short, and so is vase life (4 days tops), but sweet peas are easy to sell at farmers markets because of the lovely fragrance and nostalgic value.

Winter Plant for Transplant in Early Spring

Ageratum (A. houstonianum) Ageratum must go into the field while temperatures are still quite cool. It’s a failure as a summer cut, when it will grow into massive plants but fail to bloom. Treat it as a half-hardy annual. It won’t take frost but apparently needs cold to initiate flowering. It is reputed to be great when planted very early. A fall-blooming Louisiana native perennial, eupatorium, looks nearly identical to it.

Aster (Callistephus chinensis) Though probably not cold hardy enough to survive the winter, as half-hardy annuals, asters and false Queen Anne’s lace thrive on cool temperatures. Sow them inside January 1 and put them out in the field in February. There are 2 types of asters: bouquet, in which the whole plant is harvested, and branching, which is harvested a stem at a time. Colors are intense blues, rose and pink with a bright yellow center. They bloom in about May. Asters also succeed well when planted over the summer for fall production. Since stem length is influenced by long days, fall asters always produce longer stems than spring asters and are a little better quality than the spring crop.

Lisianthus (Eustoma grandiflora) This is a beautiful, rose-like prairie flower that has a long vase life and takes over a year to produce flowers. Start the tiny seeds inside in mid-winter and set out in spring. If seed-started in summer or fall, they will just sit there and remain very tiny through the winter. Set the small plants out in the early summer. Some won’t bloom until the following late spring, but they will make it through the winter just fine. The better approach is to order lisianthus as plugs. Cut the whole cluster of flowers as one stem, leaving about 2 sets of leaves for a second harvest. Since they are a native prairie plant, they require excellent drainage and should be grown on raised beds. Support netting is useful.

Queen Anne’s Lace (Ammi majus) True Queen Anne’s lace is a relative of the carrot and blooms the second year. Ammi majus, a half-hardy annual, is the cut flower. Common names are false Queen Anne’s lace or bishop’s weed. Started indoors under lights around January 1, sturdy, parsley-looking plants can be set out in late February. Cutting begins in April. The first, central flower of this branching plant will be both the largest and the shortest, but the lower branches will have good length. If a good market exists for long, large flowers, ignore the cutting rules for branching plants; cut down low and sacrifice the later breaks. The flower is made of hundreds of tiny flowers. Cut when about 3/4 of the tiny flowers in the head are open and the flower is beginning to get a snowy white look. This plant may cause a skin dermatitis for the harvester, so be sure to wear long sleeves when cutting to avoid unsightly welts on the arms.

Annual Statice (Limonium sinuatum)  Annual statice is a half-hardy annual and responds very well to cool temperatures. Raise seedlings inside to plant out in early spring. In the southernmost regions, statice seedlings may be planted outside in the fall. Space plants a minimum of 12” apart because the plant will produce many branches and stay in production until hot summer temperatures shut them down. Dry any unsold stems by hanging them upside down in a controlled environment. Outside drying rarely succeeds in Louisiana because of high air moisture.

Spring and Summer Plant

These are annuals that can really take the heat and humidity of a Gulf Coast summer and thrive.

Caryopteris (C. incana) Started by seeds or cuttings, caryopteris produces sturdy stems with several whorls of blue flowers in the fall. If planted out in the spring, it just makes enormous plants that won’t bloom until fall. Space would be better spent if caryopteris followed a different summer crop. Cut when the lowest whorl begins to open. It’s hard to decide how to cut. If cut deep (long), later breaks (branches) are sacrificed. Not cutting deep means more breaks, but stems are usually rather short. Decide between fewer, high-quality stems or lots of shorter stems, depending on the market available to the grower.

Celosia (C. cristata, cock’s comb, and C. spicata, wheat celosia) Celosias are tender annuals. Start seeds inside in January for transplanting in March after frost danger is past. While celosias can be direct-seeded, a better stand of plants is produced with transplants. Plants are very tender and easily killed by frost but are one of the most reliable hot-weather crops for the cut-flower grower. Space 6" to 1 foot apart. Cock’s combs seem to develop a little quicker than the wheat celosias -- about 10 weeks to first cut as opposed to 13. Cock’s combs come in rose, orange, red and yellow. Get your order in early to your seed supplier because the best red varieties always sell out quickly. Cut the main shoot, leaving a few inches for branches to develop at the bottom. It’s a little hard to tell when the combs have gotten as large as they are going to get; just guess. They’ll make a crop of smaller side shoots after the main stalk is cut. Celosias tend to mature all at the same time, so have your market lined up for large quantities in advance. Wholesalers and florists like them since they are a good material for floral arrangements for men, but they are a hard sell to the general public. Any unsold flowers can be dried and will hold their color very well. Wheat celosia, which comes in a soft pink and a burgundy, is treated exactly the same as cock’s comb, and it’s easier to judge when to cut them. The initial flower stalk will have a large central flower that will be much better developed than the other side flowers. Let the central flower open about half way up the flower and then cut. The side flowers will seem a little immature, but the overall effect will be good. The secondary stems, which come several weeks after the main shoot is cut, will be mostly unbranched with a single terminal flower. Single stems serve well for mixed bouquet work. Wheat celosia (sometimes called ‘feather’ by florists) also dries well. The spring crop of either celosia is relatively trouble-free, but the warm-weather crops will be highly attractive to a small brown moth that lays the eggs of a very hungry little caterpillar. Expect to start a regular Bt or carbaryl application when the weather warms up, or watch for the clouds of moths fluttering over the plants and kill them with malathion. Both celosias can be succession planted until about late August. Hand grooming the leaves of organically grown celosias for insect damage and frass is a thankless job

Broom corn and Colored Corn: Broom corn is a corn relative that is the material that natural brooms are made of. New varieties have a pretty red or gold seed at the ends of the stems. Although not really a cut flower, broom corn is grown to make attractive, hanging, dried arrangements. Grow broom corn and the colored Indian corns and popcorns in spring or early summer, dry them and sell in fall as an arrangement or as a material for crafters.

Cosmos (Cosmos bipinnata, C. sulphurea) Direct seeding is possible, but a fuller, more regular stand is achieved with transplants. Cosmos come in yellow/orange (easiest to grow) and bright colors. The yellows (C. sulphurea) will take considerable heat and still bloom, but the colored species will only produce well in cooler temps. Cut to a branching point to keep in production for a considerable time.

Gomphrena (G. globosa) Sometimes mistakenly called “bachelor’s buttons” in the South, the correct common name is globe amaranth. A good hot-weather plant, it provides some variety for mixed bouquets and dries beautifully. Strawberry Fields is a good, clear red, but seed is more commonly available in white, pink and a rosy purple. Gomphrena branches extensively. Remove the first flower, since it’s much too short to cut. Watch for insect damage because something (probably a beetle) eats holes in the leaves. Spray at the first sign with carbaryl, a good low-toxicity chemical used to control insects that chew holes in leaves.

Marigold (Tagetes spp.)  Start these as transplants for a good stand. Choose the large African marigold varieties. Some of the varieties, like Gold Coins and the Treasure series have huge, rounded flower heads, long stems (24") and no insect or disease problems. Marigolds only take about 10 weeks to come into production and take the heat fairly well. If marigold odor is objectionable, remove the foliage.

Sunflower (Helianthus annua) Sunflowers are a hot item, originally considered to be a “fad” by florists. The fad never passed, so breeders produced innumerable varieties. The number one lesson about sunflowers is to grow the pollenless varieties. Originally pollenless varieties were only available in yellow, but many colors have since been developed. Seed for pollen-free c.v.’s is generally more expensive than all the others but well worth it. A regular cut-flower sunflower (as opposed to giant seed producer) is beautiful when cut, but then the disc flowers in the center mature and drop pollen all over the consumer’s table, followed shortly (4-5 days) by the petals of the flower. A pollenless variety has sterile disc flowers, so it can produce neither pollen nor seed. Since it doesn’t produce pollen, it never decides that its natural function (seed production) has been fulfilled, and it lasts for two full weeks in the vase. The leaves will yellow and have to be removed, but the flower remains attractive. Sunbright and Superior Gold are the standards by which all others are judged. Plant single-stem varieties about 10" apart in late February near the coast or mid-March in North Louisiana. Branching varieties will require greater spacing. The spring crop matures in about 10 weeks, but like most summer cuts, as days get longer, production time decreases. The second or third planting can mature in as little as 5 weeks. Cut single-stem, pollenless varieties all the way to the ground because they rarely branch. Cut as soon as all the petals unfurl from the face of the dark, central disc. Don’t leave them any longer because  quality will go down as they age on the plant. Bunch and sell in 5's. Sunflowers are too bulky and awkward to wrap and may tip buckets over easily due to their top-heavy length. Locally grown sunflowers are always superior to those shipped from California. It’s common practice there to cut sunflowers before they open, which may produce knotty, deformed heads. Establish your market with the pollenless varieties and then move on to producing the colors and branching varieties. The branching varieties have smaller flower heads and are useful for bouquet work. They never have the size (5- to 6-inch-wide flower) or stem length of the nonbranchers, but who makes a three-foot-tall bouquet anyway? The colored varieties are magnificent, regardless of the short vase life. They are available in bronzes, mahoganies and reds. Florists especially love them for making men’s arrangements and for fall floral work. The earliest crop of sunflowers will have absolutely no problems, but there are a few things to watch for in warmer-weather crops. Aphids may feed on the underside of leaves. Watch for them and spray because they will discolor and twist the upper leaves that will be kept when groomed for sale. A petal-eating beetle waits for the flowers to unfurl, then eats the petals and makes the flower unsaleable. Spray with insecticide or cut the flowers the evening before they will finish opening. Kept at room temperature inside, flower heads usually open the next morning. In mid- to late summer, heads of nearly matured sunflowers may be snapped off by a weevil that lays her eggs in the flower and then girdles the stem just underneath the flower. They don’t usually destroy enough to warrant action. Sunflowers are the darling of the farmers market with their great size, summer colors and three-foot stem length. They are worth the highest price that the market will bear.

Zinnia (Z. elegans and Z. pumila) Direct seed after frost danger is past. Zinnias begin to bloom sparsely after only 4-5 weeks, but once plants develop further and begin to branch, they can be cut for months. Follow the branching-plant-cutting rules, being sure that one to two sets of leaves (leaf nodes) are left to produce new shoots. Each leaf node will produce 2 new blooming shoots with a flower on the terminal. The seed companies push Oklahoma as being mildew-resistant. It’s a pumila (small flowered) type, and while very floriferous, it tends to disappoint with its small flowers. Besides, powdery mildew is not always a problem in zinnias on the Gulf Coast. Stick with the less-expensive pumila types and the large-flowered varieties like Radiant or Benary’s Giant. The only problem that does show up in zinnias is a leaf spot disease (probably cercospora) that makes reddish spots on the lower leaves and works its way up over time. Since the lower leaves are stripped during processing, don’t worry about it. By the time the disease eventually works its way up the plant, production is nearly over anyway. Put at least 4 weeks between succession plantings or so many rows will be in production together that it will be difficult to keep up with harvesting. Zinnias are among the best of all Southern cut-flower crops because not only do they stand up to intense heat, but they rarely are marketed from other cut-flower-growing areas and are not available to local florists.

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