More intensive cultivation under shade structures can increase yields. This system requires more initial investment for infrastructure, but allows for increased planting density and yield potential. Trellis support systems vary greatly, but are generally made of vertical wood or concrete supports with wire running between them. Supports vary in height but are usually no more than 2 m (6 ft) tall to facilitate pollination once vines mature. The post and wire system allows for greater control over vine spacing compared to tutor trees. Vines will need to be maintained on 15-20 cm (6-8 inches) of a mulch substrate.
Spacing and Planting
An estimated 1,000 plants per acre is often used for establishing a commercial vanillery. Spacing recommendations are to plant vines 1-3 m (3 to 10 ft) apart with and 2.5 to 3 m (8 to 10 ft) between rows.
Vanilla can be grown in a wide range of soil types but thrives in light soils with plenty of organic material. For the tutor tree method, a slight slope may be beneficial to reduce the incidence of standing water and incidence of disease. Dry soils will require additional irrigation to maintain adequate soil moisture. Under more intensive cultivation systems, soil moisture can be regulated by managing the height of raised mulch beds.
Mulch is a popular substrate for Vanilla cultivation. The particular type of mulch is not as important as its ability to provide a slow release of nutrients and retain an optimal level of moisture for roots. Some areas rely on aged coconut husks to mulch vines. Mulch will need to be reapplied every 6 to 12 months to replenish the source of nutrients and suppress weeds. Much can be applied directly on top of the resident soil without the need for incorporation into the soil.
Pruning and Training
Vines are trained to facilitate hand pollination and harvesting in a process called looping. Vines should be looped around supporting trellises or branches as the grow. Looping vines to the ground will stimulate terrestrial roots to form, especially if they are covered in mulch, leading to stronger vines.
Looped, healthy vines from mature plants can be tipped (apex removed) to induce flowering. Vine tips are cut about 15 cm (6 inches) from the end (above the soil line) right before the dry season. These vines will be primed to flower in the coming months.
The natural rain cycles of Florida are favorable for Vanilla production. The rainy season, along with the high summer temperatures stimulates rapid growth. The drier season induces a rest period needed prior to flowering. As a result, established Vanilla plants sometimes may not require supplemental irrigation except during extremely dry periods. Vanilla plants are tolerant of short periods of desiccation. Irrigation is more critical for commercial production than in the home landscape.
Vanilla cultivation relies on the slow release of nutrients from decomposing organic material. Supplemental foliar nutrition can be applied, but scientifically-validated tests to justify this additional input are still lacking.
Insect pests generally do not typically cause serious damage. Snails and slugs, however can sometimes be problematic if not controlled. We have noticed larval feeding on young plants, but manually removed the pests.
A major limitation to Vanilla production in many regions is root and stem rot disease caused by Fusarium oxysporum. Fusarium is a ubiquitous soil-borne fungus that causes rot in many species. One specialized type (Fusarium oxysporum f. sp. radices-vanillae) causes rot in Vanilla in all major producing areas by penetrating roots and spreading throughout the plant. Typical symptoms include browning and wilting, eventually leading to death of vines. The disease can be partially controlled by good horticultural practices including the avoidance of excessive waterlogging. Fungicides and biocontrol agents can have some benefit under certain conditions. Other potential fungal diseases include anthracnose and mildew.
Harvesting and traditional curing
Beans begin to yellow at the blossom end when fully mature. Care should be taken not to harvest beans prematurely as this negatively impacts the quality of the resulting extract. V. planifolia beans that are left on the vine for too long have a higher propensity to split or mold eliminating their economic value. The exception to this is V. x tahitensis that does not display the bean splitting trait and can be left on the vine until completely brown. Individual beans should be carefully removed from the raceme in order to avoid damaging the beans.
Vanilla beans must be cured in order to develop the characteristic vanilla aroma and flavor. Curing outcomes vary greatly by location and are heavily influenced by the growing environment, plant genetics, and the maturity of beans. The curing of Vanilla beans remains somewhat of an art with many variations being used in different parts of the world. In general, curing includes a few major steps: sorting, killing, sweating, gradual drying, and conditioning.
Sorting: Beans are sorted into classes including beans 16 cm and longer, beans 12-16 cm, and small/split/reject beans. Sorting beans by size is important for the heat kill step of curing.
Heat Kill: Heat is applied at a temperature that is high enough to kill the plant cells, but not so high that the enzymes required to produce the desirable vanilla flavors would be destroyed. Water killing at 63-65°C is required to arrest cell development and start the curing process. Long beans (>16 cm) should be heated for 3 minutes, with 12-16 cm beans heated for 2.5 minutes. Smaller beans can be water-killed for 2 minutes depending on the needs for the final product. After heat killing, the beans are packed into plastic bags for sweating.
Sweating: Sweating is the process of maintaining elevated bean temperatures above 45°C for 24-48 hours after heat killing. This can be done using insulated boxes with temperature control or by placing bottles with hot (~60°C) water inside the insulated container. Beans should be dark brown after water killing and sweating.
Gradual drying: Slowly drying the beans to a final moisture content <25% is important for flavor development and control of microbial growth. This is traditionally accomplished over 12-15 days by removing the beans from their plastic bags, exposing them to direct sunlight for a few hours each day, and repacking into plastic bags at the end of sun treatment. This process could be mimicked using spaces that have temperature, humidity, and air flow control. Beans are then placed on open trays to continue drying over ~70 days. Beans are sorted by quality at the end of the drying step. Any moldy beans should be discarded as they are detected.
Conditioning: Conditioning typically takes another 1-2 months. Bundled beans should be conditioned in boxes lined with paper that is impermeable to grease and oil (eg wax paper, parchment paper, grease-proof paper). Beans should not be allowed to completely dry during conditioning.
Making your own vanilla extract
Only extract from two types of Vanilla, V. planifolia and V. x tahitensis, can be sold as “vanilla extract” under the Code of Federal Regulations (Code of Federal Regulations Title 21 CFR169.175 and CFR169.3). The regulation dictates the solvent for vanilla extract to be not less than 35% ethyl alcohol by volume with 13.35 ounces of Vanilla beans at 25% moisture content per gallon of solvent. Smaller growers may want to consider forming cooperative ventures to improve curing and storage processes, and to help ensure the uniformity and consistency of the cured Vanilla beans.
Many potential growers would like basic estimates for key inputs when considering the startup of a new vanillery. The available data is from other growing environments and production practices that will not necessarily reflect those of growers in southern Florida. Still, rough estimates can be useful when considering a new growing operation. The following answers to common questions are provided for estimation purposes only, and actual results will need to be empirically determined.
Answers to Common Questions
Q: How many years until a Vanilla vine will produce flowers and beans?
A: Meter-long cuttings will produce in 2-3 years, and smaller cuttings and tissue culture plants will take 3-4 years.
Q: How many times does a V. planifolia flower per year and when does this occur?
A: Vanilla flowers once per year usually in April-May in southern Florida.
Q: How many months does it take for a bean to ripen?
A: About 9 months after pollination.
Q: How many kilograms of green beans can one V. planifolia plant produce? How many kilograms of cured beans?
A: One healthy Vanilla plant can produce ~2 kg of green beans per plant. Curing is usually about 5:1 or 6:1 kg green bean to cured bean by weight, so each plant can produce around 0.3 to 0.4 kg cured Vanilla beans.
Q: How many cured beans do I need to obtain 1 kg of beans?
A: It will take 200-400 cured beans to make 1 kg of beans.
Q: How many plants do I need per acre?
A: Around 1,000 plants per acre is a good estimate, but this depends on the production method with more plants needed for intensive, shade house cultivation and fewer total plants when using tutor trees.
Q: Where can I obtain V. planifolia plants?
A: Tissue culture companies in both Florida and outside the USA (eg Costa Rica) can be identified by a quick internet search. Caution should be taken to ensure that these companies are selling V. planifolia or V. x tahitensis if you plan on selling “vanilla extract”.
Q: How much labor is required during pollination?
A: A general estimate is that one person can pollinate one acre of Vanilla vines. This includes monitoring the plants every day during the flowering season to pollinate freshly opened flowers.
Q: Do Vanilla flowers really need to be pollinated the morning that they open?
A: Yes, Vanilla flowers are only receptive for pollination for a short time. Temperatures can impact flower longevity, but pollinating before noon is usually optimal.
Q: Can I grow Vanilla hybrids?
A: Certainly, but the regulatory framework for some hybrids is murky. A grower must consider their buyers and consumers when considering the cultivation of Vanilla hybrids that incorporate species other than V. planifolia and V. x tahitensis. Some hybrids will be more robust and have higher disease resistance than traditional V. planifolia.
Q: How many flowers should be pollinated per raceme?
A: Usually no more than 10 beans should be allowed to develop per raceme. More could overly burden the nutritional status of the vine leading to poor vine health the following year.
Q: How long will the Vanilla vines stay in production?
A: This depends on the health of the vines, disease, and other cultural practices. You can anticipate vines staying productive for 3-5 years, but regular cycling with new, disease-free vines will aid your operation in sustainably producing beans.
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Cameron, K., 2012. Vanilla orchids: Natural history and cultivation. Timber Press.
Childers, N.F., 1948. Vanilla culture in Puerto Rico. US Department of Agriculture, Washington, D.C.
Fouche, J.G. and Jouve, L., 1999. Vanilla planifolia: history, botany and culture in Reunion island. Agronomie 19:689-703.
Havkin-Frenkel, D. and Belanger, F.C., 2018. Handbook of Vanilla Science and Technology. Wiley-Blackwell, Singapore.
Odoux, E. and Grisoni, M., 2010. Vanilla. CRC Press.