As August draws to a close, Monty Don turns his attention to autumn and tackles that perennial problem of what to grow in the shade of a tree or shrub. He also takes cuttings of his favourite pelargoniums - an essential task at this time of year. Carol Klein takes a closer look at that late summer jewel, the crocosmia, and we meet a gardener in Derbyshire who has spent a lifetime growing and showing gladioli.