Monty Don mulches the borders in preparation for spring and pots up his dahlias for the year ahead. Carol Klein celebrates her plant of the month, which can only mean the bright and beautiful daffodil. Frances Tophill heads to Barbados to offer her services to Andromeda Botanic Gardens and using the opportunity to brush up on her horticultural skills. And as part of the programmes 50th anniversary, Nick Bailey reveals the plant he thinks has had the most impact on British gardens over the last half-century.