Cut back any suffering in this way and they will put out new leaves in days, followed by autumn flowers.
Top varieties for this treatment include 'Orion' (the best early-flowering blue) and 'Patricia' (a black-eyed magenta sprawler with G. psilostemon blood).
These are both sterile hybrids so they don't set seed and have a much longer flowering period.
Other hardy geraniums have also browned and may be setting seeds. These include named forms of our meadow cranesbill, G. pratense, such as 'Mrs Kendall Clark'.
These also need cutting back to prevent unwanted seedlings, although you could save some of the seeds if you wish. These are best kept for either February or March sowing.
These summer-flowering geraniums will probably not flower again this year, but they will produce attractive new foliage. This will help keep them vigorous for next year and improve the look of a garden.
Certain sun-loving, mound-forming varieties, including the low-growing 'Mavis Simpson', 'Russell Prichard' and 'Coombland White' should be left alone as they stay compact and keep flowering.
These tend to be short-lived, however, as they flower themselves out. Propagate regularly by division in spring - every second year.
The one plant you must never cut back is the lupin, despite the foliage nearly always looking shabby by July.
This would decimate next year's flowers. Tidy it slightly if you have to.