By the end of a long growing season, a shared herb box on the balcony often looks impressively full, but underneath that lush surface the plants may already be competing hard for space, light and water. Late summer is a sensible time to step back, take stock, and sort the box out properly before autumn arrives.
Give every plant a fair share
Start by lifting each herb out carefully, one at a time, so you can see how the roots have actually spread beneath the surface. Some plants will have taken over far more space than they were originally given, quietly crowding out their neighbours in the process.
Trim back the most vigorous herbs, such as mint or chives, before replanting them, so they no longer dominate the box as soon as they go back in. A firm trim now saves the smaller, quieter herbs from being swamped again within just a few weeks.
Refresh the compost as you go, rather than simply tucking the same plants back into tired, exhausted soil. Even a partial replacement of the top layer gives the roots something new to work with as the season winds down.
Reposition the plants themselves once they go back in, placing taller or more vigorous herbs towards the back and smaller, slower growers nearer the front where they can still catch the light. This simple rearrangement often solves crowding problems on its own.
Label each herb clearly while you have everything out of the box, especially if several varieties look similar once trimmed back. This small step saves a good deal of guesswork later in the season, particularly once new growth appears and the plants no longer look quite the same as before.
Water thoroughly once everything is back in place, and keep an eye on the box over the following fortnight to make sure each herb is settling in well. A tidied box like this usually rewards the effort with noticeably fresher growth right through into autumn.
