Skip to content

What perennials cut in August or late summer, and the advantages that this method of care brings

Most perennial plants require pruning at some point. But not only spring or autumn are typical pruning seasons. Sometimes it can even be the summer months when plants are pruned. And mid-summer, and especially August, for example, is such an exceptional case. We would like to explain why you should cut back perennial plants in the first place, and also address the question “which perennials cut in August or late summer”.

Why should you cut back your plants?

Which perennials to cut in August or late summer - tips and list

August, or midsummer, is that time when the blooming season ends for many flowers, including perennials. Of course, this is a bit of a shame, because the colorful flowers were so beautiful to look at. But you still have a chance for some species to cause a second flowering period, and for this you just need to shorten the plants in August. In this way, they still have enough time to resprout and form new flowers until the cooler autumn and first frost.

Which perennials to cut in August or late summer and why pruning makes sense

Furthermore, with such cuts, but you also promote a denser growth, as well as a longer flowering period. And also, if you want to prevent self-seeding of certain perennial plants, you can do this with pruning. Because in this way it plant has no opportunity to form seeds. And then there are those perennial varieties that need pruning in order to present a magnificent and lush flowering in the future. But which perennials cut in August or late summer?

Which perennials to cut in August or late summer?

Which perennials to cut in August or late summer - Properly care for the perennial garden.

In the following, we have compiled some popular perennial species that are often found in the perennial garden and should be cut back now in midsummer. We have divided them into categories for this purpose:

Summer-flowering perennials that need pruning for next year.

Cut back splendor candle (Gaura) to rejuvenate and encourage blooms


The following summer perennials will benefit from pruning in August, especially in the future. It ensures that the plants can grow more lush and dense, but also improves the amount of flowers. Simply shorten the faded flower stems of the pretty summer perennials . Varieties that typically also lignify, but not only rid them of the faded flowers, but also trim the tips of all shoots. This measure is advantageous for short-lived perennial species, because in this way your life will be extended by a few years. Thus, pruning serves, so to speak, rejuvenation.

  • Horned violet ( Viola cornuta )
  • Cocklebur ( Gaillardia hybrids )
  • Night violet ( Lunaria annua )
  • Magnificent candle ( Gaura )
  • Purple coneflower ( Echinacea )
  • Hollyhock ( Alcea )

Tip: You can also stimulate dense and lush growth by dividing the plants. Inquire about the right time for this, depending on the type of perennial. In this article, we have once summarized which perennial plants can be divided as early as August.

What perennials cut in August to prolong or repeat flowering.

Maintain steppe sage (Salvia nemorosa) for a second blooming season

Still in the same season, again, the perennials listed below will benefit from pruning. This way, summer-flowering perennials promptly become fall-flowering perennials. Thus, some can achieve a second flowering season if they are completely pruned, while for others only the faded parts are ever removed, causing the plant to form new flowering shoots shortly thereafter. This extends the flowering period, so to speak.

Among others, the following plants achieve a second flowering:

  • Burning love ( Lychnis chalcedonica )
  • Colorful Magerites ( Chrysanthemum )
  • Fine radiant aster ( Erigeron )
  • Catmint ( Nepeta )
  • Ball thistles ( Echinops )
  • Climbing sage ( Salvia nemorosa )
  • Starthistle ( Astrantia )
  • Cranesbill ( Geranium – some species )
  • Delphinium ( Delphinium )
  • Troll flowers ( Trollius )

For these perennials, regular pruning will result in a longer blooming period:

  • Dyer’s chamomile ( Anthemis tinctoria )
  • Yellow coneflower ( Rudbeckia )
  • Golden yarrow ( Achillea filipendulina )
  • Scabiosa ( Scabiosa caucasica )
  • Sun eye ( Heliopsis )
  • Sunflower ( Helenium )

Preventing self-seeding in invasive plants

Prachtspiere self-seeds and reproduces if cut too late


There are plants that self-propagate easily and quickly. However, this is not always desirable in the home garden. You can prevent this by simply interrupting the formation of the seeds. Seeds, as you know, are formed after flowering. Thus, August, when these very flowers have withered in summer bloomers, is the best time to cap. What perennials cut in August to avoid seeding?

  • Columbine ( Aquilegia vulgaris )
  • Purple loosestrife ( Lythrum )
  • Brown cranesbill ( Geranium phaeum )
  • Three-master flower ( Tradescantia )
  • Jacob’s ladder ( Polemonium )
  • Dyer’s chamomile ( Anthemis tinctoria )
  • Flame flower ( Phlox )
  • Lady’s mantle ( Alchemilla )
  • Goldenrod ( Solidago )
  • Bellflower ( Campanula glomerata )
  • Magnificent spirea ( Astilbe )
  • Red yarrow ( Achillea )

Which perennials to cut in late summer – The last minute option

What perennials to cut in August or late summer - rejuvenate or encourage new blooms

Missed the month of August? Do not worry, because late summer is also suitable to carry out this maintenance measure in the perennial garden. There will then even be a few more specimens that you can take care of with a pruning. For example, you can cut your peonies . In principle, you can still cut back all early-flowering perennial species until late summer, when you hope for a new bloom. If flowering is now no longer so important to you, but you simply want to care for the plants and prepare them for winter, the perennials can also be pruned in autumn.