Part of a garden with winter flowers and plants in it.

How to Create a Winter Windowbox

When your summer flowers are spent, and window displays are looking bedraggled and dull, give them a quick makeover with colorful evergreens that will last the course through the coldest winter. This combination of conifers, shrubs, grasses, and herbs is guaranteed to perform for many months.

When to start: Early autumn.

At their best: Early autumn to spring.

Time to complete: 1½ hours.

You will need: Large windowbox, ericaceous potting mix, broken plastic pieces, bucket.

Selection of plants you could use: Carex oshimensis ‘Evergold’, Cupressus macrocarpa ‘Goldcrest’, Golden thyme – Thymus pulegioides, ‘Archer’s Gold’, Leucothoe Scarletta.

Before planting

Buy a frost-resistant windowbox—this one is made from terracotta, but a plastic imitation would be best if you live in a cold, exposed area that is prone to frosts. Check that your plants fit comfortably in the container.

Soak the plants

Water each plant well, either with a watering can without a rose, or by dunking the plants in a bucket of water. Allow the bubbles to dissipate, then remove the pots and allow them to drain.

Provide good drainage

Break up a plastic plant tray and add the pieces to the bottom of the windowbox. Then add a layer of ericaceous potting mix—the Leucothoe and Gaultheria are both acid-loving plants and do best in this type of soil.

Place plants in position

Place the plants in their original pots in the windowbox and make sure that they will sit about 1 in (2 cm) below the rim when planted to allow sufficient space for watering.

Plant up and firm in

Plant up and fill in around each plant with soil, firming it in with your fingers as you go. Water well. Water your box once or twice a week in winter, and more frequently in spring.