Alan Titchmarsh is walking through a beautiful British bluebell wood. Although bluebells were present in our ancient wild woods, they were scarce, kept in check by a dense tree canopy that blocked out the light. Bluebell numbers then increased when humans began to chop the forest down. Open glades sprang up all across the country and these bright open spots were perfect for bluebells. Britain has more than half the world population of bluebells, so if it did not thrive here it would probably be extinct by now.