Acreage and Plant Densities of Commercial Carambola, Mamey Sapote, Lychee, Longan, Sugar Apple, Atemoya, and Passion Fruit Plantings in South Florida

ing. However, the reduction in net CO2 assimilation on a hydraulic conductivity of highbush blueberry. Physiol. Plant. 43:13- whole plant basis is still great after unflooding due to the 18. reduction of leaf area. 14. Eliasson, L. 1978. Effects of nutrients and light on growth and forma tion in Pisum sativum cuttings. Physiol. Plant. 43:13-18. Flowering and fruiting. Under normal conditions, caram- 15. Gomez, K. A. and A. A. Gomez. 1984. Statistical procedure5 for ag bola fruit retention is markedly lower than fruit set (7). In ricultural research, second edition. John Wiley and Sons, New York. this study, flooded trees retained the greatest number of 16. Hodkinson, K. C. and H. G. Becking. 1977. Effects of defoliation on fruit. Therefore, flooding stress possibly increases fruit re root growth of some arid zone perennial plants. Aust. J. Agric. Res. 29:31-42. tention of carambola. However, more research is needed 17. Hook, D.D. and J. R. Scholtes. 1978. Adaptations and flood tolerance inthis area. of tree species, pp. 299-331. In: D. D. Hook and R. M.M. Crawford In summary, 'Golden Star' carambola appeared to be (eds.). Plant life in anaerobic environments. Ann Arbor Sci. Publ., somewhat flood tolerant and has the ability to recover from Ann Arbor, Michigan. flooding stress with respect to net gas exchange. However, 18. Janzen, D. H. 1967. Synchronization of sexual reproduction of trees within the dry season in Central America. Evolution 21:620-637. both continuous and intermittent flooding result in de 19. Khairi, M.M. A. and A. E. Hall. 1976. Temperature and humidity creased biomass accumulation. In addition, flooding of effects on net photosynthesis and transpiration of Citrus. Physiol. carambola appears to slightly increase flowering and fruit Plant. 36:29-34. 20. Knight, R. J., Jr. 1982. Partial loss of self-incompatibility in 'Golden set. Star' carambola. HortScience 17:72. 21. Knight, R. J., Jr. 1982. Response of carambola seedling populations Literature Cited to Dade County's oolitic limestone soil. Proc. Fla. State Hort. Soc. 95:121-122. 1. Alben, A. O. 1958. Waterlogging of subsoil associated with scorching 22. Kozlowski, T. T. 1984. Flooding and plant growth. Academic Press, and defoliation of Stuart pecan trees. Proc. Am. Soc. Hort. Sci. Orlando, Florida. 72:212-223. 23. Kramer, P.J. 1951. Causes of injury to plants resulting from flooding 2. Andersen, P. C, P. B. Lombard, and M. N. Westwood. 1984. Effect of the soil. Plant Physiol. 26:722-736. of root anaerobiosis on the water relations of several Pyrus species. 24. Kramer, P. J. 1983. Water relations of plants. Academic Press, Or Physiol. Plant. 62:245-259. lando, Florida. 3. Box, G. E. P., W. G. Hunter, and J. S. Hunter. 1978. Statistics for 25. Loustalot, A. J. 1945. Influence of soil moisture conditions on appar experimenters. John Wiley and Sons, New York. ent photosynthesis and transpiration of pecan leaves. J. Agr. Res. 4. Burroughs, W. J. and D. J. Carr. 1969. The effects of flooding on 71:519-533. the root system of sunflower plants on the cytokinin content in the 26. Magness, J. R. 1953. Soil moisture in relation to fruit tree function xylem sap. Physiol. Plant. 22:1105-1112. ing. Rep. Int. Horde. Congr., 13th, 1952. 1:230-239. 5. Campbell, C. W. 1965. The 'Golden Star' carambola. Fla. Coop. Ext. 27. Orchard, P. W., H. B. So, and R. S. Jessop. 1985. The response of Serv. Circ. S-173. sorghum and sunflower to short-term waterlogging: III. Root growth 6. Campbell, C. W. 1985. Carambola industry in Florida. HortScience effects. Plant and Soil 88:421-430. 20:16. 28. Pereira, J.S. and T. T. Kozlowski. 1977. Variations among woody 7. Campbell, C. A. 1987. Caramboa fruit development and storage in angiosperms in response to flooding. Physiol. Plant. 41:184-192. Florida. M.S. Thesis, Univ. of Florida, Gainesville. 29. Phung, H. T. and E. B. Knipling. 1976. Photosynthesis and transpi 8. Catlin, P. B., G. C. Martin, and E. A. Olsson. 1977. Differential sen ration of citrus seedlings under flooded conditions. HortScience sitivity of Juglans hindsii, J. regia, Paradox hybrid, and Pterocarya 11:131-133. stenoptera to waterlogging. J. Amer. Soc. Hort. Sci. 102:101-104. 30. Ploetz, R. C. and B. Schaffer. 1989. Effects of flooding and 9. Childers, N. F. and D. G. White. 1942. Influence of submersion of Phytophthora root rot on netgas exchange and growth of avocado. the roots on transpiration, apparent photosynthesis, and respiration Phytopathol. 79:204-208. of young apple trees. Plant Physiol. 17:603-618. 31. Sena Gomes, A. R. and T.T. Kozlowski. 1984. The effects of flooding 10. Cody, R. P. and J. K. Smith. 1987. Applied statistics and the SAS on water relations and growth of Theobroma cacao var. Catongo programming language, second ed. Elsevier Science Publishing Co., seedlings. J. Hort. Sci. 61:265-276. New York. 32. Smith, M. W. and P. L. Ager. 1988. Effects of soil flooding on leaf 11. Crane, J. H. and F. S. Davies. 1985. Responses of rabbiteye blueber gas exchange of seedling pecan trees. HortScience 23:370-372. ries to flooding. Proc. Fla. State. Hort. Soc. 98:153-155. 33. Syvertsen, J. P., R. M. Zablotowicz, and M. L. Smith, Jr. 1983. Soil 12. Crane, J. H. and F. S. Davies. 1988. Flooding duration and seasonal temperature and flooding effects on two species of citrus: I. Plant effects on growth and development of young rabbiteye blueberry growth and hydraulic conductivity. Plant and Soil 72:3-12. plants. J. Amer. Soc. Hort. Sci. 113:180-184. 34. Westwood, M. N. 1978. Temperate-zone pomology. W. H. Freeman 13. Davies, F. S. and J. A. Flore. 1986. Flooding, gas exchange, and and Co., San Francisco.

Proc. Fla. State Hort. Soc. 102:239-242. 1989.

ACREAGE AND PLANT DENSITIES OF COMMERCIAL CARAMBOLA, MAMEY SAPOTE, LYCHEE, LONGAN, SUGAR APPLE, ATEMOYA, AND PASSION FRUIT PLANTINGS IN SOUTH FLORIDA

Jonathan H. Crane Additional index words. Tropical fruit crops, plant density. University of Florida, IFAS Abstract. A survey of seven commercial tropical fruit crops Tropical Research and Education Center grown in south Florida was conducted to determine current 18905 S.W 280 St. acreage, total number of trees, primary cultivars, grove ages, Homestead, FL 33031-3314 and predominant plant spacings. Current acreage is as fol lows: carambola (Averrhoa carambola L), 435; mamey sa- Florida Agricultural Experiment Station Journal Series No. N-00071. pote (Calocarpum sapote (Jacq.) Merr.), 267; lychee (Litchi The author gratefully acknowledges the assistance of the Research Com mittee of the Tropical Fruit Growers of South Florida, Inc. chinensis Sonn.), 190; longan (Euphoria longana (Lour.)

Proc. Fla. State Hort. Soc. 102: 1989. 239 Steud.), 72; sugar apple (Annona squamosa L), 49; atemoya The survey form was used to record the number of (Annona cherimola Mill, x A. squamosa L), 47; and passion acres and trees, cultivars grown, area planted and number fruit ( Passiflora edulis Sims), 20 acres. Most of the carambola, of trees of a particular cultivar (if available), number of lychee, longan, atemoya, and passion fruit acreage is 4 years acres and trees at a particular plant spacing, and tree ages. old or younger. In contrast, more than half the mamey sapote Groves of < 100 trees per acre were considered planted at and sugar apple acreage is 5 years old or older. Most caram low density; 100 to 200 trees per acre, moderate density bola, lychee, and sugar apple acreage is planted at moderate and >200 trees per acre, high density. Effort was made to plant densities while most mamey sapote, atemoya, and lon contact all commercial growers with established and new gan acreage is planted at low plant densities. Intermediate plantings. within-row plant spacings (e.g., 15 ft, 20 ft) are favored by many growers, while some utilize close within-row plant Results and Discussion spacings (e.g., 10 ft.) with the idea of removing trees upon crowding. Acreage and production of these tropical fruit crops South Florida currently has approximately the follow are expected to increase in the near future. The survey infor ing numbers of commercial growers: carambola, 68; mation should be useful in determining possible research and mamey sapote, 30; lychee, 40; longan, 20; sugar apple, 16; marketing needs for these crops. atemoya, 9; and passion fruit, 13. However, the number of commercial growers and plantings will most likely in crease in the near future due to increased consumer de South Florida's commercial tropical fruit acreage has mand and the high prices obtained for these crops (5). historically been dominated by avocados, 'Tahiti' limes, Dade and Lee Counties have commercial plantings of and mangos (13, 18). Recent figures estimate south Florida all 7 crops. Small acreages of lychee and carambola can be has 11,239 acres of avocados, 6,792 acres of limes, and 2,895 acres of mangos (1). Many other tropical fruits such found in Broward and Palm Beach Counties, respectively and some interest has been shown in establishing plantings as papaya, acerola, sapodilla, guava, banana, mamey sa pote, and lychee have been grown commercially on a for all these crops in Collier County. minor scale (i.e., <400 acres each) for the past 20-30 years Carambola. About 435 commercial acres of carambola are currently in south Flcrida. Eighty-nine percent of the (2, 3). During the past 5-10 years, commercial acreage of acreage is 4-years-old or younger. Ninety-four percent carambola, atemoya, sugar apple, longan, and passion fruit (410 acres) is planted to sweet cultivars and 6% (25 acres) has been established and acreage of mamey sapote and to tart cultivars. There are about 50,858 carambola trees lychee has increased (4, 5, 11, 12). Papaya, acerola, in commercial plantings; 97% (49,050 trees) of the trees sapodilla, and guava acreages have remained near previ are sweet cultivars and 3% (1,808 trees) are tart cultivars. The predominant sweet cultivar is 'Arkin' and predomin ous levels. Recommended cultural practices and cultivars have ant tart cultivar 'Golden Star'. The sweet cultivar Twang been described for carambola (6, 9), mamey sapote (7, 17), Tung', is grown commercially to a very limited extent. lychee (8, 14), longan (3, 14, 15), sugar apple (4, 11, 16), Seventy-seven percent of carambola acreage is planted atemoya (4, 10, 11), and passion fruit (4, 12). However, at moderate plant densities (e.g., 145 trees/acre) (data not little information is available on the current acreage and shown). Of that 77%, 58% is set at 6 moderate plant spac plant spacings employed by commercial growers of these ings (Table 1). Low density plantings (e.g., 69-87 trees/ crops. With this in mind, an extensive survey was con acre) account for about 18% of the acreage (Table 1). ducted of south Florida groves with the objective of deter About 5% of the acreage is planted at high density (e.g., mining the current acreage, number of trees, primary cul 290 trees/acre or more) with the majority of that acreage tivars, grove ages, and plant densities and spacings. This utilizing a 10 ft x 15 ft spacing (data not shown). information may be of value to the tropical fruit crops Interplanting of low and moderately spaced carambola industry (e.g., growers, packers, marketers) in determining trees is a common practice in south Florida. Generally, the future trends in production and marketing and in helping interplanted species is a fast growing fruit crop such as identify possible research needs. papaya or banana which affords the young carambola trees

Materials and Methods Table 1. Carambola plant density and percentage of acreage at various The bulk of the data reported in this study was com spacings. piled by the Research Committee of the Tropical Fruit Growers of South Florida, Inc. and the author during the Plant Number of Plant spacing trees per Percent of summer of 1988. Initial and subsequent computations and density (ft) acre total acreage updates (Nov., Dec, 1988; Jan., 1989) were carried out by the author. The last update occurred during May 1989 Moderate 15x22 132 16 and is reported here. Moderate 15x20 145 15 Moderate 15x25 To obtain the desired data, the Research Committee 116 11 Low 25x25 69 11 composed a list of commercial growers. A survey form was Low 20x25 87 7 designed by the author and used when interviewing com Moderate 20x20 108 6 mercial growers by telephone or in person. Commercial Moderate 12.5x25 139 5 carambola growers were defined as growers with 50 or Moderate 16x23 118 5 Misc.z 24 more trees, while plantings of 25 or more plants of mamey — — sapote, lychee, longan, sugar apple, atemoya, and passion 'Various plant densities and spacings, each accounting for less than ^ ,v fruit were considered commercial. of carambola acreage.

240 Proc. Fla. State Hort. Soc. 102: 1989. some wind protection and the grower early income. When Table 3. Lychee plant density and spacing and the percentage of acreage crowding occurs, the interplanted papaya or banana plants at various spacings. are easily removed. Generally, high density plantings are Plant Number of not interplanted and are designed to be hedged and top Plant spacing trees per Percent of ped to form hedge-rows as they mature. density (ft) acre total acreage Mamey sapote. South Florida currently has about 267 acres and 23,267 mamey sapote trees in commercial pro Low 25x30 58 14 174 14 duction. About 60% of the acreage is 5 or more years old Moderate 10x25 Moderate 20x20 108 12 and the predominant cultivars are 'Pantin' ('Key West') and Moderate 12.5x25 139 12 'Magana'. Selections like 'Prolific', 'Cuban No.2', and 'Pace' Low 20x25 87 8 are also planted to a limited extent. Low 25x25 69 6 Fifty-nine percent of the mamey sapote acreage is plan Low 25x26 67 6 Moderate 15x25 116 5 ted at low plant densities (e.g., 48-96 trees/acre) (data not Misc.7 — — 23 shown). Most (54%) low density plantings utilize 18-25 ft within row and 25-30 ft between row spacings (Table 2). zVarious plant densities and spacings, each accounting for less than 5% Moderate plant densities account for 40% of the acreage, of lychee acreage. with the 15-20 ft within row and 16-20 ft between row plant spacings accounting for 32% of the acreage. Only Most (58%) of the longan acreage is planted at low den 1 % of the acreage is planted at high density and all of this sities (e.g., 41-91 trees/acre). Of that 58%, 56% have trees set at 20-30 ft within rows and 25-30 ft between rows uses a 10 ft x 20 ft spacing. Lychee. South Florida has about 190 acres of lychee. (Table 4). Thirty-five percent of the acreage is planted at Thirty-four percent of the acreage (64 acres) is planted to moderate densities (e.g., 108-145 trees/acre). Seven per cent of the plantings are set at 10 ft x 20 ft spacing (Table 'Brewster', 65% (124 acres) to 'Mauritius', and 1% (about 2 acres) to miscellaneous cultivars. Similarly, of the 16,690 4). As with lychee and mamey sapote, interplanted or dou total trees in commercial production, 34% (5,686 trees) are ble-set longan groves are common. Tree removal is recom 'Brewster', 65% (10,820 trees) are 'Mauritius', and 1% (184 trees) are of other cultivars (mostly 'Bengal'). Nearly 71% mended when crowding begins since longan trees have the potential to get quite large (35 ft high and 45 ft wide) (15). of the commercial lychee acreage is 4-years-old or less. Sugar apple. South Florida has about 49 acres and 5,261 Low density (e.g., 40-96 trees/acre) lychee plantings ac count for about 45% of the total lychee acreage while 52% sugar apple trees in commercial production. About 40% of and 3% of the acreage is planted at moderate (e.g., 103-174 the acreage is 4-years-old or younger. Sugar apple growers generally plant seedlings of known or unknown parentage trees/acre) and high (e.g., 217 trees/acre) densities, respec because there appears to be little variability among seedl tively (data not shown). Most low (34%) and moderate ing trees and seedlings are precocious bearers (16). (43%) density groves utilize just 4 different plant spacings About 49% of the sugar apple acreage is at moderate (Table 3) while a 10 ft x 20 ft spacing is used in all high (e.g., 108-174 trees/acre) plant densities while 22% and density groves (data not shown). 28% are at low (e.g., 48-96 trees/acre) and high (e.g., 223- Low density groves are typically interplanted with a 290 trees/acre) plant densities, respectively (data not precocious fruit crop (e.g., sugar apple, banana) and many shown). Forty-eight percent of the sugar apple acreage is of the moderately dense groves are double-set (e.g., 10 ft set at 5 different moderate plant spacings, 11% at a wide x 25 ft, 12.5 ft x 25 ft) within rows (Table 3). In both cases, spacing (30 ft x 30 ft), and 8% at a close spacing (10 ft x tree removal is planned for interplanted trees because of the large size (40 ft tall and wide) of mature lychee trees 20 ft) (Table 5). Generally, moderate and high density sugar apple plantings are not interplanted while many low density Longan. South Florida has about 72 acres and 7,297 sugar apple plantings are the result of sugar apple trees longan trees in commercial production. The predominant being used as the interplant among another fruit crop cultivar grown is 'Kohala' and about 69% of the acreage is 4-years-old or less. Table 4. Longan plant density and spacing and percentage of acreage at various spacings.

Table 2. Mamey sapote plant density and spacing and percentage of acre Plant Number of Percent of age at various spacings. Plant spacing trees per total acreage density (ft) acre

Plant Number of 19 Percent cf Low 20x25 87 Plant spacing trees per 25x30 91 12 acre total acreage Low density (ft) 11 Moderate 12.5x25 139 11 26 Moderate 12.5x24 145 Moderate 20 x 20 108 20x30 72 11 30x30 48 20 Low Low 69 9 86 10 Low 25x25 Low 18x30 7 10 High 10x20 217 Low 20 x 30 72 30x30 48 5 20 x 25 87 9 Low Low 108 5 69 5 Moderate 20x20 Low 25 x 25 10 20 Misc.z ^ Misc.'

'Various plant densities and spacings, each accounting for less than 5% 'Various plant densities and spacings, each accounting for less than 5% of longan acreage. of mamey sapote acreage. 241 Proc. Fla. State Hort. Soc. 102: 1989.