Ideas for Cool-Weather Windowboxes
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 Its Best: Early autumn to spring
Time to Complete: 1 1/2 hours
- large windowbox
- ericaceous potting mix
- multipurpose potting mix
- broken plastic pieces
- carex oshimensis 'Evergold'
- cupressus macrocarpa 'Goldcrest'
- Golden thyme, Thymus pulegioides 'Archer's Gold'
- Leucothoe Scarletta
- stipa tenuissima
- Japanese tassel fern, Polystichum polyblepharum
- winter-flowering pansies, Imperial Antique Shades
- Cupressus macrocarpa 'Goldcrest'
- Grape hyacinth, Muscari
- Narcissus 'Topolino'
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.
Extend the Season
This colorful windowbox makes a bright winter display with a mixture of pansies and textured evergreens. Then, as the weather starts to warm up, blue grape hyacinths and dainty daffodils (not in flower here) appear in succession to keep the interest going throughout spring.
Plant Up Bulbs
Follow Steps 1 to 3. Evenly space the narcissi bulbs on the layer of soil, and plant the rest of the plants carefully between them.
Fill in around the plants and cover the bulbs with soil, up to about 3 in (8 cm) from the rim. Add a few grape hyacinth bulbs between the plants and then cover with soil to about 1 in (2 cm) from the rim. Firm gently and water.
Top Tip: Caring for Pansies
Winter-flowering pansies will bloom throughout the cold winter months, although they put on their best performance in spring. Remove the dying flowers as you see them, and if plants become straggly in spring, renovate them by cutting the stems back to 3 in (8 cm). Then apply an all-purpose fertilizer and water in well.