August 2003

The Herb Revolution By Rick Schoellhorn

Having just finished a great group of educational programsat the Southeast Greenhouse Conference, I feel obligated to focus on a group ofcrops that are often misunderstood and sadly shy of production information.

Herbs offer most growers a huge opportunity to make someextra money. They can be used in many of the same ways that ornamentals can and(theoretically) you can eat them as well, but when growers move into the herbmarket, there are a few production issues to consider. Additionally, cultivarselections make a big difference in the greenhouse and the landscape.

Production issues

Most growers mix their herbs with bedding plants and growthem under the same conditions, which implies that they are being grown forornamental use. The question becomes: Are you growing edible or ornamentalherbs? Semantics? You should consider the question carefully because if yougrow edible herbs, you will need to use different pesticides than you wouldwith ornamental crops. (There are not a lot of chemicals labeled for edibleherb production.) Herbs fall somewhere in the gray area between ornamentalcrops and vegetables, currently they are a little bit of a red-headed stepchild, as chemical labels usually do not mention any herb crops. So, to be bothmoral and profitable, you’ll need to check with experts and see what is labeledfor these crops. A good reference is the article by Dr. Jamie Gibson listedunder the resources portion of the article.

Want to grow organic herbs? It is a great niche, but youneed to know what is required to get organic certification for your crops. Fororganic certification, you will need to use different fertilizers and managethe crop entirely separate from any ornamentals. Check out the publicationsfrom ATTRA (Appropriate Technology Transfer for Rural Areas), an organizationfunded by the U.S. Department of Agriculture; their organic herb productionpublication is a great overview athttp://attra.ncat.org/attra-pub/PDF/om-herb.pdf.

Marketing Issues

Producing and controlling a 4-inch crop of herbs ischallenging; sales can be unpredictable, and overgrown pots can be difficult tomove. Most 1-gal. herbs are too large for consumers to rationalize buying afull complement of varieties, so how can you maximize on this high dollarmarket? The market is moving to the herbal mixed container, and here’s whereyou can really add value to your crops. Decorative containers, window boxes andhanging baskets with a complement of the more common herbs are hot items rightnow; even apartment dwellers can be potential customers when they can get aninstant kitchen garden. You will need to speak with your suppliers, selectcultivars with compatible growth habits and avoid large forms. I have neverseen a good looking hanging basket of dill, which doesn’t mean it can’t bedone, but the point is to look for plants with a growth habit that will lookgood and last in mixed or specialty containers.

Vegetative or seed? It gets a bit confusing as to whichherbs to grow from seed and which to grow from cuttings. Here’s a shortbreakdown: Vegetative propagation of certain herbs is recommended for a varietyof reasons. Seed produced forms may vary too much in flavor and habit to getreliable quality. Many of the variegated or foliage interest types do not cometrue from seed, plus some herbs are a bit tricky to propagate, so buying inyour liners may be the best bet. Examples of herbs produced from cuttings wouldbe lavender, rosemary, tarragon, certain basils, marjoram, oregano, mint, sageand thyme. Herbs easily produced from seed include chives, cilantro, dill,fennel, parsley and some of the hybrid basils.

Types of Herbs

Basil (Ocimum basilicum and hybrids). Lots and lots of cultivars are available, bothvegetative and seed produced. How do you select which is right for you? Mostgrowers look for the dwarf forms, as they have a better pack or 4-inchperformance, but some of the larger forms are nice as well. There are some newcultivars with colorful flowers on the market so that the herb and ornamentalcrossover of these crops is really nice. Just because you are going to eat themdoesn’t mean they can’t be good looking as well.

Two highly flowered cultivars of Ocimum basilicum areavailable. ‘Magic Mountain’ and ‘Kasar’ have large, salvia-like spikes of pinkto violet flowers and good flavor. ‘Purple Ruffles’ is an older cultivar withpurple ruffled foliage; newer purple forms are less disease (Fusarium) proneand may do better in production. Ocimum x ‘Spicy Globe’ and other similarcultivars have a clove/cinnamon taste and a compact habit. ‘African Blue’ islarger cultivar with green leaves splotched purple and pale blue-white flowers.

Cilantro or culantro.These are totally different plants with very different growth habits, but bothhave the soapy taste of cilantro. If you are growing cilantro (Coriandrumsativum) —by the way, it is thesame herb as coriander; coriander is the seed, cilantro the foliage — thisherb has a habit of bolting when under any stress, such as heat, drought, insectpressure, etc., so maintain cool, bright light conditions. Cilantro is veryfast growing, so cut back on fertilizer when plants are 2-21/2 inches indiameter to keep them from outgrowing their pots and to reduce stretch. As withmost seed-produced herbs, it is best to drop multiple seeds per cell so thatyou get a fast, full pot that will be ready to sell as soon as possible.Culantro (Eryngium f?tidum) is a much slower crop with fewer hassles, butit is also not as well known and may be a bit tougher sell without some effort.The foliage has a stronger flavor that is used in most Caribbean cooking.

Dill (Anethum graveolens), fennel (Foeniculum vulgare)and parsley (Petroselinum crispum). Theseare all closely related genera with similar requirements in production; cooltemperatures and bright light are essential. All are quick crops from seed, orthey can be purchased as liners to make them a 2- to 3-week turnover crop.Again, in 4-inch production, cut back on fertility when plants are 2-3 inchesin diameter so they don’t overgrow their containers.

Lavender. There is aproliferation of new lavender hybrids on the market. Lavender is aMediterranean crop, meaning it prefers low humidity, good air circulation andlower water levels. In general, you want to avoid afternoon watering, as mostof the disease issues arise from water on the foliage for extended periods.English and French lavenders are the connoisseur’s choice Á forfragrance. Spanish lavenders (Lavandula stoechas) have colored petals arisingfrom each spike like rabbit’s ears and are good, tough garden or containercrops. For Southern growers, most lavenders will suffer in the summer; bestoptions for Southern growers include Fernleaf, French and sweet lavenders. Note:Lavender does better with a slightly higher pH than most other herbs; 6.5-7.5is best. Other forms to look for include Lavandula dentate, which is good fornorthern and western climates, and the Madeira series (Lavandula stoechas).

Mint. There are manyflavors, growth habits and foliage colors. Mint (Mentha species) is usually avery vigorous crop, so 4-inch production is difficult because the plants growin so quickly that they have a short sales window. This is a great crop to sellas a 6- to 8-inch or 10-inch basket. Other forms to look for include Mentha xgracilis, Mentha piperita ‘Variegata’ and pineapple mint, a variegated formwith a pineapple-like fragrance.

Oregano (Origanum vulgare) and marjoram (Origanummajorana). Both of these crops are fromthe same genus Origanum, and taxonomists debate if they are even differentspecies; their growth and production are very similar. Easily grown from seedor purchased as liners, they are sold without flowers and can be turned oververy quickly. Gourmets will tell you that the best oreganos are those producedvegetatively, as they retain superior fragrance and taste. Look for cultivarswith variegated and yellow foliage, which acts to boost sales and also makesfor a great component plant in mixed containers. Other forms to look forinclude Origanum aureum ‘Crinkle Leaf’; Origanum onites ‘Aureum’; gold potmarjoram; Origanum dictamnus or Greek oregano, ornamental not culinary;Origanum rotundifolium ‘Kent Beauty’, also ornamental, totally different lookwith nodding green bracted spikes of pink flowers, good in baskets.

Thyme (Thymus vulgaris). This group of herbs is less well known in many markets. In general, itprefers very dry, well-drained conditions and low humidity, but the plants arevery tough and cold hardy. Thyme needs some air, so it is not the best choicefor mixed containers where crowding will lead to disease problems, but it is agreat plant for use between stepping-stones in the landscape. Other forms tolook for include Thymus x citriodorus ‘Doone Valley’, which has gold and greenfoliage and pink flowers, and Thymus praecox or creeping red thyme, which hasdeep pinkish red flowers and green foliage.

Chives and shallots.Of these two onion relatives, only chives (Allium schoenoprasum) seems to havea really strong market. Easily grown from seed or purchased as liners, this isa very quick crop in the greenhouse. From liners, production takes 3-4 weeksfor a 4-inch crop. Mostly sold when still juvenile, the flowers of chives are areal plus later in the season. Leaves and flowers are edible, and given brightlight, chives are tolerant of a variety of production conditions. Shallots(Allium cepa) are less commonly grown, but the crop is sold as the mature leafbase used in cooking. As a result, it is primarily grown in the field and solddry packaged. Shallots offer a small gourmet niche, but not necessarily as agreenhouse crop. Other forms to look for include anew chives series called Buster.

Rosemary (Rosmarinus hybrids). Luckily, rosemary is an easy-to-grow crop. It prefers very brightlight, slightly drier soil conditions and good air circulation. Large, uprightgarden forms are available that merit 1-gal. production, and creeping orprostrate types are excellent in hanging baskets. In the West, rosemary makesan excellent landscape plant; for those of us in the North and South, a goodannual. Southern growers will want to make sure plants are protected fromafternoon rains to avoid disease problems. Other forms to look for includeRosmarinus officinalis ‘Albus’, a white flowered form; Rosmarinus officinalis’roseus’ a pink flowered form; Rosmarinus officinalis ‘prostratus’ or weepingrosemary; and Rosmarinus officinalis ‘Haifa’, another prostrate form.

Sage. Oh for a sagethat would thrive in the Deep South. Luckily, the rest of the country has a lotof wonderful alternatives. From the classic, seed-produced Salvia offinalis toall the wonderful new vegetative forms, there is a lot to select from. Purplefoliage, variegated, large leaved, small leaved, etc. Check with your suppliersand see what is available locally. In general, the more variegation on theplant, the slower it will grow, and for this crop, bright light is essential.Other forms to look for include Salvia officinalis ‘Icterina’, a yellow greenvariegation.

Tarragon (French, Russian, and Mexican). Here is the problem child of the herb group, TrueFrench tarragon (Artemisia dracunculus var. sativa) is the undisputed tarragonof choice. Best flavor but lots of production issues, and dormancy-relatedproblems mean you really need to get this plant in as a vegetative liner.Bright light, cooler conditions and low fertilization produce best results.Russian Tarragon (Artemisia dracunculus subsp. Dracunculoides) is notconsidered to have the good qualities of French Tarragon but is more readilyavailable. If you have a high-end market, you’ll want to stick with Frenchtarragon or commit the horrible social gaffe of supplying the inferior variety.Lastly, for those of us in the Deep South who cannot keep either of the abovetwo growing all season, try Mexican tarragon (Tagetes lucida), which is a toughmarigold relative with a similar flavor and a lot better performance under heatand humidity. You won’t fool Emeril, but you’ll have a good substitute foryankee tarragon.

Conclusion

Any way you slice it, you will definitely be attracting anew audience by offering herbs as well as ornamentals. If you are going toinvest in an herb program, do it right. Make selections that will do well in yourregion of the country, provide the right conditions for optimal growth and, forthe sake of all of us, use the correctly labeled pesticides on these crops.Once the product leaves your nursery, even something sold as an ornamental islikely going to be used as an edible crop or at the least handled by customerswho assume that the crop is pesticide free. If you are a retailer, stress theimportance to customers of washing any herbs well before using them. We can allappreciate a well-grown plant, but a huge part of the gardening experience issmell and taste as well, so realize this and plan accordingly.