Shrubs

• Boxwood shrubs will grow for several consecutive seasons in a window box.Polka Dot/Polka Dot/Getty Images
  
  Boxwood, heaths, heathers, dwarf Alberta spruce and most dwarf conifers will survive the winter months in a window box. For added warmth and to dress up your outside decor, decorate these trees with small holiday light sets. Be sure to keep them watered well, because just like indoor plants, shrubs and dwarf conifers grown in a container rely on you for hydration. Check the soil daily, about mid-morning, to see if it is moist or dry. Normally soil in winter window boxes will not dry out as fast as it does during the summer.
  
  

Foliage Plants

• Prevent ivy grown in window boxes from attaching to the side of your home.Photos.com/AbleStock.com/Getty Images
  
  Kale, flowering cabbage, ivy and parsley provide season-long color. Select a variegated ivy and allow it to spill over the side of the window box to help soften the look. Harvest parsley and kale to use in recipes throughout the winter. Kale leaves sweeten once they have been exposed to frost. Flowering cabbage is a rather large plant once it reaches maturity, so keep this in mind when selecting other plants to combine with it in the window box.
  
  

Bulbs

• Florist cyclamen, which is not hardy, grows in a window box.Jupiterimages/Goodshoot/Getty Images
  
  Paperwhites, florist cyclamen and hardy cyclamen are ideal bulbs for winter window boxes. Paperwhites are a tender bulb, thus are better to grow in window boxes in warm climates. Several varieties of cyclamen are hardy and thus ideal for gardeners in cold northern climates. Grow paperwhites and florist cyclamen toward the back of the winter window box to accommodate their height. Hardy cyclamen is low-growing, thus better positioned near the front edge of the window box so its tiny pink or white flowers are easier to enjoy.
  
  

Annuals and Perennials

• Pansies bloom almost non-stop from fall through spring.Jupiterimages/Comstock/Getty Images
  
  Hellebore, flowering sweet pea, pansy and viola are colorful winter flowering plants that can add plenty of pizazz to window boxes. Sweet peas and pansies are annual plants, which means they grow, flower, set seed and die in one growing season. Select a bush sweet pea that states on the package it is a winter flowering variety. Sow the seeds in late summer so they have time to germinate and grow before winter sets in. Plant pansies in the early fall so they can establish their root system before winter. Hellebore and viola are perennials, which means they come back from their own root system year after year. Plant these in mid-to-late summer so they have plenty of time to establish. Hellebore, depending on variety, may bloom as early as November.