I live in Zone 4. I have a deck 8 ft off the ground that gets high winds early in summer. I have a corner pergola on the deck and a large planter box below it. It’s south facing and full sun. I’m looking for ideas of long-flowering climbers that can grow and overwinter in place. This sounds like a tall order, but I have a couple of ideas to see what you think. The Lonicera periclymenum “Scentsation” is one potential I’ve considered. Another is the paniculata Hydrangea “Pink Diamond”, if pruned to enable it’s height to advance. I would greatly appreciate any feedback on these and any other ideas or suggestions you might have.
Thank you for contacting the Toronto Master Gardeners. When planting on a balcony you need to consider few things:
- The soil dries out faster due to high winds and the simple fact that plants are in containers. Are you planning to add a drip line to the planter bed to supplement rain water?
- Growing plants in containers in an exposed site like a balcony means your plants will need a bit more TLC to stay healthy; you will need to water and fertilize more often, and offer more protection from the elements, since the higher up your balcony is located of the ground, the colder the air becomes
- For a perennial climber to overwinter, the larger and more insulated the planter box/container the greater the chance that the vine will survive the winter, also don’t forget to make sure there are adequate drainage holes in the bottom of the planter box.
Lonicera periclymenum “Scentsation is a very showy vine with extremely fragrant yellow flowers blooms from mid-spring to late summer, followed by bright red berries. This vine grows best in full sun to part shade in moist well-drained soil. This long blooming vine will be is a wonderful addition to your garden.
Hydrangea paniculata ‘Pink Diamond’ is not a climbing vine but is a very vigourous up-right large deciduous shrub which can grow up to 15′ if left to grow on its own. This shrub is best grown in organically rich, medium moisture, well-drained soils in full sun to part shade and will not be a suitable choice for your planter box.
You might like to consider planting a Clematis. Clematis vines prefer sunny locations (at least six hours of sun needed for blooming) but the soil should be kept cool. An easy way to accomplish this is by planting some type of ground cover or shallow-rooted perennial plants around the clematis. A 2-inch layer of mulch can also be incorporated to keep the roots cool and moist.
One clematis that has been bred for pots and may be suitable is Climador or ‘Konigskind’. This variety of clematis stays relatively short, has blue/purple flowers and is suitable down to zone 3. It reportedly can survive in a pot over the winter with some protection.
I found an article: Six Vines that Grow Well in Containers by Bill Marken, Suzanne DeJohn, and The Editors of the National Gardening Association from Container Gardening For Dummies, 2nd Edition
https://www.dummies.com/how-to/content/six-vines-that-grow-well-in-containers.html, quite relevant to your question. It is important to note that the vines Bougainvillea, Mandevilla and Star Jasmine are not hardy in our climate and will have to be treated as annuals. You may wish to plant an annual vine. There are many benefits to planting annual vines; annuals unlike perennials which have a limited flowering period are bred for continuous flowering throughout the growing season. Also, by planting annuals, winterizing the planter box is not necessary.
If you decide to overwinter your container remember that the soil must be moist when the plants are stored to help protect the roots. Covering your planter with anything from evergreen boughs, blankets, bubble wrap or burlap around the planter helps. Remove the coverings once the weather warms.
We wish you much success and pleasure with your new adventure on your terrace.