Pots and containers of summer flowers are reaching the end of the road by early autumn, and it’s time to hold off on the watering. This not only helps to conserve a precious resource, but saves time and effort that will not be paid back with much in the way of flowers from now on. The majority of plants will have slowed or even stopped their flower production, and no amount of watering, or feeding come to that, will keep them going.
So take the bull by the horns, and get on with the important job of dismantling your summer displays. You’ll be able to sort out what to keep and what to compost, and get on with some essential bulb planting. The sooner those snowdrops, crocus and daffs go in the better, so they can start to get their roots down and finish flower bud formation!
What to do with summer container plants overwinter
It is also time to take stock of what you are going to try and keep over winter. In some cases, the plants will not be worth it, but reliable tender perennials like cannas, salvias, pelargoniums and fuchsias are all worth potting up singly to overwinter in a cool greenhouse, shed or garage. Don’t move them inside immediately, however, simply keep them growing outside to establish in their new pot and wait until overnight temperatures really start to take a tumble (below 2-3C) later in the autumn.
Apart from an initial soak to keep them happy, they should then be kept on the dry side, so that new leaf growth is kept to a minimum. This will also start the dying back process so that the plants go into a semi-dormant state which will help them get through the winter when you move them inside. Don’t feed these plants either.
As for any hardy perennial plants, they can either be left in-situ or potted up individually as required. You might even decide to plant them out in a garden border – something which I often do, after growing them on to a larger size in a mixed container display for the summer. Small shrubs, herbaceous perennials and alpines are all suitable for this treatment.
Any true annuals or tender perennials that aren’t worth keeping overwinter can now be discarded. Put any disease-free remains, including roots and top growth, on the compost heap. Here they will rot down to recycle this valuable organic matter and the nutrients it contains.
What to plant in containers for winter and spring
And then, of course, it’s time to plant up your pots and containers for spring. Empty out the compost, breaking it up with your fingers to remove any large clods and use it to re-fill the container to around two-thirds their depth. You can plant your spring bulbs in layers, into this compost as you re-fill. Then top up the container with some fresh, peat-free compost, and plant up the top with a mix of plants that will look good over winter and into next spring. Spring bedding, dwarf evergreens shrubs, winter-flowering heathers, evergreen ferns, grasses and carex are just a few things to go for – there are plenty more!
See my popular YouTube video for more inspiration and details on how to replant your containers for winter. Summer might be on the wane, but there’s so much planning and planting to do that will help keep your garden looking good.