1. Carambola / Star FruitBelimbing (Averrhoa carambola L.)

2. Botanical Description The star fruit tree is slow-growing, short-trunkedwith a much-branched, bushy, broad, roundedcrown and reaches 6 - 9 m in height. Its deciduous leaves, spirally arranged, arealternate, imparipinnate,15 - 20 cm long, with 5to 11 nearly opposite leaflets, ovate or ovate-oblong,4 - 9 cm long; soft, medium-green, andsmooth on the upper surface, finely hairy andwhitish on the underside. 3. Pruning will keep the tree from getting toolarge while still allowing it to bear fruitprolifically. A good tropical fruit tree for limited space. 4. The leaflets are sensitive to light and more orless inclined to fold together at night or when thetree is shaken or abruptly shocked. Small clusters of red-stalked, lilac, purple-streaked,downy flowers, about 6 mm wide, areborne on the twigs in the axils of the leaves. The showy, oblong, longitudinally 5- to 6-angledfruits, 6.5 -15 cm long and up to 9 cm wide, havethin, waxy, orange-yellow skin and juicy, crisp,yellow flesh when fully ripe. 5. The fruit has a more or less pronounced oxalicacid odor and the flavor ranges from very sour tomildly sweetish and tastes something like a mixof apple, pineapple, and kiwi fruit. The so-called "sweet" types rarely contain morethan 4% sugar. Slices cut in cross-section have the form of astar. There may be up to 12 flat, thin, brown seeds1/4 to 1/2 in (6-12.5 mm) long or none at all. 6. A. Leafy shoots B. Inflorescence C. Flower D. L/S of FlowerE. Fruit F. C/S of Fruit G.Seed 7. Origin and Distribution The star fruit is believed to have originatedin Ceylon and the Moluccas but it hasbeen cultivated in southeast Asia andMalaysia for many centuries. It is commonly grown in the provinces ofFukien, Kuangtung and Kuangsi insouthern China, in Taiwan and India. 8. It is rather popular in the Philippines andQueensland, Australia, and moderately soin some of the South Pacific islands,Guyana, and in Guam and Hawaii. There are some specimens of the tree inspecial collections in the Caribbeanislands, Central America, tropical SouthAmerica, and also in West Tropical Africaand Zanzibar 9. VarietiesThere are 2 distinct classes of star fruit: the smaller, very sour type, richly flavored,with more oxalic acid; the larger, so-called "sweet" type, mild-flavored,rather bland, with less oxalicacid. 10. Climate Classed as tropical and sub-tropical becausemature trees can tolerate freezing temperaturesfor short periods and sustain little damage at 3C. It can grow up to an elevation of 1,200 m (inIndia). Requires moisture for best performance; ideallyrainfall should be fairly evenly distributed all year(In Australia, it is claimed that fruit quality andflavour are best where annual rainfall is 1800mm). 11. Soil No particular preference for soil type; thestar fruit does well on sand, heavy clay orlimestone, but will grow faster and bearmore heavy fruits in rich loam. It is often chlorotic (show burn symptoms)on limestone soil. It needs good drainage; cannot standflooding. 12. Propagation The star fruit is widely grown from seedthough viability lasts only a few days. Onlyplump, fully developed seeds should beplanted. In damp peat moss, they willgerminate in one week in summer, require14 to 18 days in winter. The seedlings aretransplanted to containers of light sandyloam and held until time to set out. Theyare very tender and need good care.Seedlings are highly variable. 13. Air-layering has been practiced andadvocated. However, root formation isslow and later performance is not whollysatisfactory. Inarching is successful in India, shield-budding in the Philippines and theForkert method in Java. Trees can be top-workedby bark-grafting, a populartechnique in Java. 14. For mass production, side-veneer graftingof mature, purplish wood, onto carambolaseedlings gives best results:- the rootstocks should be at least 1 yearold and 1-1.5 cm thick.- grafted trees will fruit in 10 months fromthe time of planting out.- mature trees can be top-worked by bark-grafting. 15. Cultural Practices The tree needs full sun. A spacing of 6 m has been advocated but if thetrees are on good soil no less than 9 m shouldbe considered. Trees 2.5 - 3 m high respond well to 0.5 kgapplications of N, P, K, Mg in the ratio of 6:6:6:3given 3 to 4 times per year. If chlorosis occurs, it can be corrected by addediron, zinc and manganese. Some advisersrecommend minor-element spraying 4 timesduring the year if the trees are on limestonesoils. 16. Moderate irrigation is highly desirableduring dry seasons. Heavy rains during blooming seasoninterfere with pollination and fruitproduction. Inter-planting of different strains isusually necessary to provide cross-pollinationand obtain the highestyields. 17. Harvesting and Yield In Malaysia, they are produced all the yearround The fruits naturally fall to the ground when fullyripe. For marketing and shipping they should behand-picked while pale-green with just a touchof yellow. Trees that received proper attention haveyielded 45 to 115 or even 135 kg of fruit per tree 18. Pests and Diseases The carambola is relatively pest-free except forfruit flies. In Malaya, fruit flies (especially Dacusdorsalis) are so troublesome on carambolas thatgrowers have to wrap the fruits on the tree withpaper. Experimental trapping, with methyleugenol as an attractant, has reduced fruitdamage by 20%. Reniform nematodes may cause tree decline. 19. Anthracnose caused by Colletotrichumgloeosporioides may be a problem Leaf spot may arise from attack byPhomopsis sp., Phyllosticta sp. orCercospora averrhoae.- Cercospora leaf spot is sometimesreported in Malaysia, (but widelyoccurring in Ceylon, China and in thePhilippines as well). 20. Plant Facts: Common Name: Star Fruit, Carambola Botanical Name: Averrhoa carambola Family: Oxalidaceae Plant Type: Deciduous tree Origin: Ceylon and the Moluccas Form: Short-trunk with a much-branched,bushy, broad, roundedcrown 21. Height: to 12 m Rate of Growth: Slow Salt Tolerance: Low Soil Requirements: Not too particular asto soil, but will grow faster and bearmore heavily in rich loam. Needs gooddrainage; cannot stand flooding. 22. Water Requirements: Medium droughttolerance Nutritional Requirements: Balanced liquidfertilizer monthly, side dressings ofcomposted manure Light Requirements: Full sun 23. Leaves: Deciduous leaves, spirally arranged,are alternate, imparipinnate, 6 to 10" long,with 5 to 11 nearly opposite leaflets, ovate orovate-oblong, 1 1/2 to 3 1/2" long; soft,medium-green, and smooth on the uppersurface, finely hairy and whitish on theunderside. The leaflets are sensitive to lightand more or less inclined to fold together atnight or when the tree is shaken or abruptlyshocked. 24. Various forms of terminal leaf 25. FlowersSmall clusters of red-stalked, lilac,purple-streaked, downy flowers, areborne on the twigs in the axils of theleaves. 26. Flowers 27. FruitsShowy, oblong, longitudinally 5- to 6-angled fruits, have thin, waxy, orange-yellowskin and juicy, crisp, yellowflesh when fully ripe. Slices cut incross-section have the form of a star.Flavour ranges from very sour to mildlysweetish. May be up to 12 flat, thin,brown seeds or none at all. 28. Fruits 29. Pests or diseases:- Fruit flies,- black beetles,- stinkbugs,- nematodes,- anthracnose,- leaf spot, 30. Fruit fly 31. Dacus dorsalis attacking fruit 32. Fruit borer (Cryptophlebia encarpa) 33. Symptom on young fruit caused byLymantriid larva (Porthesia scintillans) 34. Archips tabescens Walka Lepidopteran larva attacking young fruit 35. Adoxophyes privatana WalkLepidopteran larva attackingnew shoots & young leaves 36. Indarbela disciplaga SwinchFrass left behind by stem borer (left)larva within the stem (right) 37. Fruit wrapped to avoid insect anddisease attack 38. Propagation: Cuttings, air-layering,or seeds 39. Bud grafting 40. Cantuman baji sisi(Side veneer grafting) 41. Technique for planting star fruit onex-mining land 42. Popular Clones 43. Dome-shaped canopy of B2 clone (L)Elliptical shaped terminal leaflet of B2 clone (R) 44. Young shoot of B2 reddish brown in colour 45. Flower on terminal branch of B2 clone(light purple in colour) 46. Dome-shaped canopy of B10 clone (L)Young leaves of B10 turned upwards (R) 47. Young leaves of B10 reddish in colour (top)Flower on terminal branch purplish in colour 48. Differences between stamen length and stigma oftwo clones B2 and B10 49. Dome-shaped canopy of B17 clone (L)Leaf base of leaflets raised (R) 50. Various forms of canopy