Tropical gardens rely more on foliage for their colour than bedding plants. By using plants with leaf colour one also gets a show the whole year round. To create interest in a tropical garden the foliage should be big bold and dramatic. Use contrasting colours and plant in bold groups to really make the foliage pop.
For maximum impact, position plants with red, yellow, orange, pink, purple leaves near each other. There are many shrubs that flower with the bold foliage to add to the look. Just think back to gardens along the KZN coast from your summer holidays. There are always plants such as hibiscus, ornamental ginger, bougainvillea and even canna lilies that flower in abundance and will provide further contrast to the vibrant ground covers and the trees above.