It is time to take a good look at your herbaceous borders. By now, many plants will have flowered and need cutting back. If this leaves gaps, the nursery is full of colour –Rudbeckias, Crocosmia, Penstemon, Summerina, Heleniums and Kniphofia. Professionals plan borders so there is a succession, always something of interest. If you are not quite that clever, the easy way is to buy a few plants in flower every week or two and pretty soon you too will have a professional long-season border.