Plant Focus: Bougainvillea ‘Tom Thumb' Bougainvillea ‘Tom Thumb' is a compact plant (about 50 x 70 cm) with small lilac bracts. One cannot miss bougainvilleas when they are in full flower. Looking magnificent, they hang over walls, form dense impenetrable hedges, mimic bright carpets over pergolas and create explosions of colour in large containers. The warmer the summer, the prettier they become. Bougainvilleas are primarily classified as creepers or semi-creepers.