Terrace Container Gardening

(Question)

I have a large terrace with NW exposure and is sheltered by a 6 foot wall. The condo is in the Beach area of Toronto so very close to the lake. I am looking to make an empty space into an intimate garden oasis. Direct sunlight is limited during the day. I would like to plant Scentsation’ Honeysuckle along 2 walls in smallish containers and dwarf cypress and dwarf Japanese maple to ground the area. Will these selections succeed.

 

(Answer)

Thank you for contacting Toronto Master Gardeners with your interesting gardening question.Your choice of ‘Scentsation’ Honeysuckle Lonicera periclymenum ‘Scentsation’ is a beautiful and fragrant choice which should do well in your sun/part shade environment and is reputed to be hardy down to zone 3. (The rule of thumb is to go at least one zone lower than your local zone, Toronto is zone 6 for plants in containers to remain outdoors in winter.)

Containers for the plants you suggest must have drainage holes in the bottom, and must be at least 5 cm wider than the nursery pot. I suggest that you avoid a metal container which can heat up tremendously in sunshine, and ceramic which will not withstand our winter conditions. Many fibreglass containers come in elegant styles and colours and withstand our winter weather. I have a healthy dwarf white pine which has been living outside in a plastic pot for four years.

Planting the honeysuckle: water the plant thoroughly before planting. Place some good quality potting soil in your chosen container. Remove the nursery pot and spreading out the roots, position the plant along with its supporting cane leaning onto your wall or trellis with the rootball at the same height as in the nursery pot. Fill your container with potting soil, firming as you go. Arrange and tie the stems onto the support. Water well and keep well watered during the plant’s first year. We suggest an application of 10-10-10 plant food at the beginning of each new growing season.

The best trees for containers are small and slow growing with compact root systems. Evergreens that are cold hardy in Toronto will need to be rated at zones 4 or 5 when in a container. Dwarf cypress appears to be a questionable survivor in our climate, however, Chamaecyparis or False Cypress would be a suitable choice and hardy to zones 4 and 5 and there is a great variety of colour, foliage and form available. Because evergreens transpire throughout the winter, they must be kept watered right up until the soil ball freezes hard. Spread out the roots at potting up for all plants.

Acer palmatum or dwarf Japanese Maples grow well in containers with a lovely variety of foliage colour and form, upright or pendulous in habit.

Overwintering your containers: Soils must be moist when the plants are stored to help protect the roots. Covering with anything from evergreen boughs, blankets, bubble wrap or burlap around the pots helps. Remove the coverings once the weather warms. Raising the pots off the deck with ‘pot feet’ or pieces of wood allows water to escape through the drain holes and protects from splitting or cracking in freeze-thaw cycles.

We wish you much success and pleasure with your new adventure on your terrace.