all-weather-space bark bottle-shaped bottle-tree branched ceiba-chodatii conservatory deciduous display displayed distinctive dome exotics floss-silk-tree flower-dome gardens Gardens-by-the-Bay glasshouse gnarled greenhouse grotesque horticultural horticulture indoors inside palo-borracho shape shaped shapes Singapore South-American stored-water subtropical surface surfaces swollen-trunk texture textures tree tropical trunk unusual utilitarian vegetation warty-tree