Bring Plants Indoors, Wrap Up Containers

By Christina Da Silva

Shorter days and the arrival cooler temperatures should have condo gardeners scurrying around getting ready for winter.

Now is the time to bring herbs, tender perennials and balmy tropicals indoors and to insulate outdoor containers. With frost on the way, the tropicals – hibiscus, bougainvillea, heliotrope, fuchsia and even the classic annuals (geranium, coleus, impatiens and begonias) migrate indoors.

Slowly introduce the plants to the indoors: outside during the day, and indoors at night. Gradually increase the time spent indoors until they remain indoors 24/7. Only condos with bright south facing or west facing windows have the right conditions for herb survival. Bring in bay and rosemary before the first frost.

Not all herbs require warmer temperatures. Mint, chives and tarragon not only survive the winter in insulated pots they need frost to grow well next year.

Now comes the hard part. Before bringing them in, cut back plants to one-quarter of their original length, flowers and all. Ensure that no bugs hitchhike indoors with the plants by watering the pots until water pours out through the bottom.

Bugs lurk on the underside of leaves, so remember to spray both sides of the leaves with a diluted soapy water mix (a few drops of dish detergent in a litre of water).

Because of space limitations, bringing in pots may not be a viable option. Cuttings, which take less room, offer an alternative for saving your favourite plants. Take cuttings from the healthiest plants and root the stems indoors. By spring, the cuttings will have developed into container-ready plants.

Not all pots are made equal. Ceramic and terra cotta pots, which crack at the first sign of frost, should be emptied and stored upside down in a sheltered spot. Tough frost-resistant containers are a must for over-wintering perennials, shrubs and trees as well as for fall and winter displays. There are plenty of choices, including metal, stone, wood, plastic, fibreglass or good quality plastic resin pots. Shoots are more cold hardy than their roots. For example, Japanese maple (Acer palmatum) grown in the ground can survive -20C, whereas temperatures between -5 and -10C will kill its roots.

Since the ground and snow cover provides excellent insulation, you don’t need to worry about plants in garden beds. It’s a different story for container gardens; pots don’t provide as much protection to sensitive roots. So, perennials, shrubs and trees over-wintering in pots on balconies require extra insulation from late October to April.

Insulating pots needn’t be expensive. Consider recycling newspapers. Crush newspapers into enough balls to fill a plastic bag. Then tie or tape the plastic bag around the pot. Bungee cords also work well. Besides newspaper, other more conventional insulation material includes Styrofoam slabs or bubble wrap.

Cluster the pots together in a wind-sheltered, shady spot. Surround the more tender plants with hardier specimens. Then cover the assortment of pots with a plastic tarp, leaving part of it open for air circulation. Autumn isn’t only about protecting plants; it’s also a time to create dazzling fall containers and plant spring bulbs.

Replace the summer annuals with fall bloomers, such as mums, asters, pansies, ornamental kale and heather. Later on, these containers can change into soothing winter displays of conifers, dogwood twigs and seed pods.

Fall is also the time to plant spring flowering bulbs – tulips, daffodils and crocuses – in large insulated containers. Keep the soil moist, not wet. Place the pots in a sheltered spot, away from the wind and sun. Then sit back and relax, knowing a colourful spring is guaranteed.