How to create privacy on condo terrace using containers

(Question)

Hello, I have a 200 sq ft terrace that is partially shaded (sun between 9:30 am -2 pm). Using containers I want to create a privacy “wall” of about 10-12 ft wide using plants that will grow as tall as possible as fast as possible.

I tried to grow annual ivy last year and found it took too long to grow tall and around the trellis I placed in the containers. It was beautiful, but not what I was looking for. Last year I also had a rose bush, which did really well and grew about 5 feet tall. We took it inside for the winter and it’s back on the patio and still alive.

This year, I’m wondering if adding rose bushes would be a good option or if there is something else I could plant in those containers that would produce the privacy I’m looking for.

Note that I live in a small condo so will not be able to bring in more than one plant. I’m not sure how these container plants would survive the winter wind and cold but without much snow at all.

I really look forward to your response!

Many thanks,
Louise

(Answer)

Hello – Great to hear that your rose bush pulled through! I suggest using a combination of perennials including roses and ornamental grasses as well as fast growing annual vines to achieve the privacy you are after.

First of all, if you are adding additional large containers and soil be sure to check with your building management for regulations on the use of balcony space, safety concerns and weight considerations.

It would be great to add another rose and one or more tall, ornamental grass to get the height you are looking for.  A feather reed grass such as the variety Karl Foerster (Calamagrostis acutiflora‘Karl Foerster’) is a good choice.  This grass grows 3-5 ft. with a narrow, vertical profile. This is a full sun grass but should be fine with part afternoon shade. ‘Avalanche’ another feather reed grass cultivar has attractive variegated foliage and a more compact size (2-4 ft.) You could grow these plants as annuals given you have limited space to overwinter plants indoors.  However, it may be possible to overwinter the plants on your balcony using four-season containers or other winter protection and reduce the expense of replacing the plants every year.

A 4-season  container is typically insulated such that it will withstand the changes in temperature throughout the seasons. The freeze-thaw cycle is the main problem; that is, the melting of the water in the container’s soil during sunny or warmer spells, followed by freezing when the temperatures dip again.A previous post on our site has information on insulating containers.

https://www.torontomastergardeners.ca/askagardener/winterize-ornamental-grass-in-container/

Another consideration when selecting plants that will successfully overwinter on your balcony is to choose plants from a hardiness zone one or two lower than the zone for your location. The feather reed grasses noted above are hardy to zone 4 whereas Toronto is generally considered to be zone 6.

As for vines, there are a number of possibilities.  My favourite annual vine is morning glories (Ipomea purpurea) which will grow 6-10 ft. in a season. Another possibility is scarlet runner bean (Phaseolus coccineus), which is a climbing bean plant that produces beautiful red flowers and then beans that you can eat.  Both of these vines can be grown from seed or you can purchase plants at your local garden centre.

Two tropical vines that we treat as annuals here are Black-eyed Susan vine and Mandevilla vine. The Black-eyed Susan vine (Thunbergia alata), with orange, yellow or white flowers grows 3-8 feet and will bloom all summer.  A Mandevilla vine (Mandevilla sanderi), a tropical with deep green leathery leaves and huge flowers in pinks to reds that blooms all summer grows 3-10 ft. Both do well in full sun to part shade.

I hope some of these suggestions will appeal to you.  It may take some experimentation to find the best plants that will work for your situation but that’s part of the fun of gardening.  Thanks for contacting the Toronto Master Gardeners.