3338 



THUNBERGIA 



THUNBERGIA 



The thunbergias are nearly all vigorous greenhouse 

 climbers resembling allamandas in habit. In large con- 

 servatories where they are not cramped for room they 

 flower freely and display their flowers to the best 

 advantage. Severe pruning, which is necessary in small 

 greenhouses, prevents the production of flowers. The 

 larger species, T. laurifolia, T. affinis, T. grandiflora, 

 T. mysorensis, and T. coccinea are rapid growers, 

 requiring plenty of feeding and root-room. All do 

 better in open beds than in pots. They may be propa- 

 gated either from seeds or by cuttings which are taken 

 from the young wood which starts into growth after the 

 plants have been cut back during winter. These pro- 

 duce few flowers the following autumn, but bloom 

 freely the second season. As a rule, the plants flower 

 in late summer or autumn, but the time of flowering 

 may be made to vary according to treatment in some 

 species. T. data and its varieties and T. fragrans are 

 often treated as annual garden plants, flowering in late 

 summer. T. erecta and T. affinis, when grown in pots, 

 form rather compact shrubby plants (see Gn. 24, p. 314; 

 30, p. 292, -47, p. 150). In Porto Rico T. alata has escaped 

 and is common. Cook writes that there are two forms, 

 one with corolla-limb cream-yellow and other whitish. 

 Thunbergias and allamandas are great favorites in 

 central and southern Florida, being used on verandas, 



3802. Thunbergia alata. ( X W) 



arbors, small trees, old stumps, trellises and buildings. 

 Of the blue-flowered kinds T. grandiflora is hardiest and 

 commonest. It has large heart-shaped leaves which 

 overlap one another in a charming manner. It blooms 

 from September until Christmas, the flowers being light 

 blue and rather dull. The form of T. laurifolia known 

 to the trade as T. Harrisii, has nearly sky-blue flowers, 

 of a deeper but brighter hue than the preceding. It is a 

 taller-growing and choicer plant, and has ten or more 

 flowers in a raceme, while those of T. grandiflora are 

 solitary in the axils. T. fragrans is the common white- 

 flowered kind. The form cultivated in Florida is proba- 

 bly var. vestita, as the blossoms are not fragrant. T. 

 alata is a general favorite. The flowers range from buff 

 and white to orange with a deep purplish brown 

 throat, the last form being the most popular. This 

 species is killed to the ground by sharp frost every 

 winter but sprouts vigorously the following spring. It 

 also comes up from self-sown seed. This species grows 

 only 7 to 8 feet high. All the thunbergias mentioned 

 above are easily raised from cuttings or layers in 

 summer. T. erecta is not a climber but has a some- 

 what straggling habit. It has small dark green leaves 

 and large deep purplish blue gloxinia-Eke flowers 

 which are white at the base. There is a pure white 

 variety of it. It blooms all summer and autumn. It is 

 readily raised from cuttings during the rainy season 

 (H. Nehrling.) 



affinis, 1. 

 alata, 2. 

 alba, 2, 4. 

 alhiflora, 2. 

 aurantiaca, 2. 

 Backerii, 2. 

 Bakeri, 2. 

 cserulea, 4. 

 chrysops, 6. 



INDEX. 



coccinea, 10. 

 Doddsii, 2. 

 elegans, 11. 

 erecta, 4. 

 fragrans, 3. 

 Fryeri, 2. 

 grandiflora, 7, 8. 

 Harrisii, 8. 

 intus-alba, 2. 



laevis, 3. 

 laurifolia, 8. 

 lutea, 2, 9. 

 mysorensis, 9. 

 natalensis, 5. 

 sulphurea, 2. 

 unicolor, 2. 

 vestita, 3. 



KEY TO THE SPECIES. 



A. Fls. axillary, solitary. 



B. Lvs. entire : l. 



BB. Lvs. angularly toothed. 



C. Petioles winged 2. 



cc. Petioles not winged. 



D. Color of fls. white: corolla-lobes 

 truncate and sinuately toothed 



at the apex 3. 



DD. Color of fls. blue (white only in 



varieties). 

 E. Plant erect or suberect. 



F. Lvs. petiolate 4. 



PF. Lvs. sessile 5. 



EE. Plant climbing. 



F. Throat of the corolla, yellow. 6. 

 FF. Throat of the corolla white . 7. 

 AA. Fls. in terminal or axillary racemes 

 (see, also, T. grandiflora). 



B. Color of fls. blue 8. 



BB. Color of fls. yellow 9. 



BBB. Color of fls. scarlet 10. 



11. 



affinis 

 alata 



fragrans 



erecta 

 natalensis 



chrysops 



grandiflora 



laurifolia 

 mysprensis 

 coccinea 

 elegans 



1. affinis, S. Moore. A rambling shrub, 10-12 ft. 

 high, smooth: branches 4-angled: Ivs. short-petioled, 

 elliptic, acute, entire: fls. 2 in. across, deep purple-blue, 

 with a yellow throat. Summer. Trop. Afr. B.M. 6975 

 G.C. III. 2:461. G.M. 32:291. This plant is closely 

 allied to T. erecta, from which it differs by its entire 

 Ivs. and larger fls., which are about twice the size 

 of those of T. erecta. When grown in a pot the plant 

 forms a compact shrub, but when given more room it 

 is a rambling climber. 



2. alata, Bojer. BLACK-EYED SUSAN. Fig. 3802. St. 

 square, climbing, hairy: Ivs. opposite, triangular-ovate, 

 hastate, repand-toothed, rough-pubescent, tomentose 

 beneath; petioles winged, about as long as the Ivs.: 

 fls. solitary, on axillary peduncles; calyx very small, sur- 

 rounded by 2 large inflated bracts; corolla-tube some- 

 what longer than the involucre, dark purple within; 

 limb rotate, oblique, of 5 rounded segms., buff or cream- 

 colored. S. E. Afr. B.M. 2591. P.M. 2:2. B 5'238 

 (not good). L.B.C. 11:1045. J.H. III. 48:11. G.L. 

 27:38. A perennial climber which may also be treated 

 as an annual greenhouse plant. Usually prop, by seeds. 

 It is used either as greenhouse climber or to grow on 

 trellises outdoors. Outside it flowers mostly in Aug., 

 but by prop, at various times plants may be had in blos- 

 som nearly the whole year in the greenhouse. There 

 are many varieties, some of which have been described 

 as species. 



Var. alba, Paxt. (T. alata var. albiflora, Hook.). 

 Fls. white, with a blackish center. P.M. 3:28. B.M. 

 3512. Var. aurantiaca, Kuntze (T. aurantiaca, Paxt.). 

 Fls. bright orange, with a dark center. The best of the 

 group. P.M. 6:269. H.U. 1, p. 355. Subvar. D6ddsii 

 has variegated Ivs. P.M. 15:221. F.S. 4:415. Var. 

 Bakeri, Hort. (T. Bakeri or Backerii, Hort.). Fls. pure 

 white. Var. Fryeri, Hort. (T. Fryeri, Hort. T. alata 

 var. intm-dlba, Hort.). Pale orange, with a white 

 center. Var. sulphfcrea, Hort. Fls. sulfur-yellow. Var. 

 Ifttea, Hort. (T. alata var. unicolor, Hort.). Fls. 

 entirely yellow. 



3. fragrans, Roxbg. St. slender, climbing: Ivs. 

 lanceolate to triangular-ovate, cordate or subcordate, 

 mostly angularly toothed on each side of the base, 

 rough on both sides, petiolate: fls. white, axillary; 

 corolla-tube narrow; limb spreading, 1}^ in. across, 



