It certainly feels like the summer borders have peaked too soon! Perennials that would usually still be sitting pretty have given us a fine display and gone to seed. But all is not lost, I believe there’s still time to get a second flush of flowers by cutting some of them back.
Salvia nemerosa plants produce spikes of blue or pink flowers in summer and, when the flowers have faded, they leave attractive seed spikes that look good in winter. I cut back half of the spikes and chance another flurry, if it doesn’t happen I still have structure for winter interest.
Geraniums can be cut back hard once they have flowered, especially those that are rampaging across the border. This chop will stimulate a fresh crop of lush leaves to keep the garden looking good.
Nepeta, adored for its silvery foliage, purple/blue flowers and attractiveness to bees, will be looking tired now. Cutting it back hard will produce new leaves and another flush of flowers; it will also prevent it self seeding all over the place. If you do want to grow more, save the seeds in a brown paper bag and sow them in spring.
Alchemilla mollis is another rampant self seeder. Nail scissors are ideal for snipping off the clusters of yellow ochre seed plumes.
Cut back any other perennials that are looking a bit sorry for themselves to improve the appearance of the garden leaving ornamental grasses such as stipa tennuisima to waft in the summer breeze and cover any temporary gaps.
Seed saving is a fantastic way of replenishing your borders. Plants like foxgloves, lupins, campanulas, stachys and poppies produce seed heads readily. Snip these off and store them in a paper bag. Keep them in the fridge and re sow in spring.
There are lots of plants that have gone to seed but should be kept for their structural contribution to the garden in winter. These include ornamental grasses such as calamagrostis Karl Foerster and stipa gigantea. Perennials such as bronze fennel and artichoke keep the height in the border while teasels and spent sunflowers are a fantastic food source for birds that need to fill up before their journey overseas for winter.
If your garden is lacking in colour and you have a few gaps then add some rudbeckias and heleniums. The yellow and orange flowers of these late perennials will keep the interest going in your garden well into autumn.