Discover the Joy of Container Gardening

Grow organic vegetables, seasonal favourites, trees and healthful herbs in moveable mini-gardens.

Credit: Carolyn Herriot

allium container gardening

I came upon the joy of container gardening 10 years ago when I knew I’d be moving from my fully planted home garden and half-acre nursery garden.

I immediately stopped planting in the ground, which is when I discovered just about any plant can look great in a pot. It’s only a matter of choosing the right container. I happily plant up anything that will contain a growing medium, from olive-oil cans to old boots, even when it means I have to punch drainage holes out first. Container gardening is perfect when you live in a townhouse with a small patio, or an apartment with a balcony.

Maybe you’d like to add some interest at your front door or some colour outside a window? You can grow anything in containers: bulbs, winter and summer annuals, perennials, climbing plants, herbs and veggies, all of which provide pleasure from spring through winter. Succulents are my favourites and there’s no end to the drama they provide, especially when they flower, which just puts the icing on the cake! Try growing lettuce, radishes, green onions, zucchinis, tomatoes or scarlet runner beans in planters. Herbs, being Mediterranean plants that thrive in hot, dry conditions, are perfect for planters in full sun. Pick fresh sprigs of mint, chives, oregano or basil from a pot outside your kitchen door. I find basil and peppers produce best when grown in two-gallon black plastic pots, and harvest huge yields of tomatoes, cucumbers, tomatillos and eggplants from five-gallon pots positioned in the hottest spot in my garden.

In cedar boxes on a sundeck plant climbing roses, clematis or honeysuckle with bulbs for spring colour and lavender for summer fragrance. Massing colourful planters together is all the rage in gardening circles. When a planter has passed its best, simply replace it with another, just coming into its best show. This way you always have a fabulous display. Many gardeners don’t realize that in a large-enough container and with proper care, young trees and shrubs can thrive for at least five years. Enjoy them in containers, then have the benefit of an instant garden when you finally plant them. Figs, bay trees, weeping birches, willows, maples, bamboo, roses and many evergreens make garden-worthy container specimens.

TIP: Use a dolly to move large potted plants around more easily. I guarantee you’ll thank me for this advice.

My Favourite Container Plants:

(Plants are hardy to the zone number indicated) • Nandina domestica (heavenly bamboo): for year-round interest; hardy to zone 6. • Myrtus communis (myrtle tree): train it into a tree shape to accent its exquisite flowers and evergreen foliage; hardy to zone 8. • Acer palmatum ‘Fireglow’ and ‘Bloodgood’ (red leaves): for sun; hardy to zone 6.

succulents in container

Rosa rugosa: for trouble-free beauty and fragrance; hardy to zone 2. Try ‘Hunter’ (a R. rugosa hybrid hardy to zone 4) for a fragrant repeat-bloomer.
Corokia cotoneaster: for a quirky conversation piece; hardy to zone 9.
Pieris japonica ‘Variegata’: for flowers and foliage interest; hardy to zone 6.
Leycesteria formosa (Himalayan honeysuckle or pheasant berry): for spectacular flowers; hardy to zone 9.

When growing plants in containers, be aware that they are effectively exposed to two extra zones of coldness. In other words, a zone-5 plant (in the ground) becomes a zone-7 plant in a pot. When roots are grown above ground they are subjected to more frost damage. One way of getting around this is to either move the pots of borderline hardy plants under the eaves against the house, or into a greenhouse, conservatory or garage where they get frost protection.

TIP: A good way to protect roots from freezing is to place a pot inside a larger one and stuff the space between with an insulating material, such as burlap or landscape fabric. It’s often not cold temperatures that destroy overwintered plants, but the combination of heavy winter rains followed by a deep freeze that kills their roots. Keeping planters undercover prevents this from happening. All container plantings need the right growing medium and close attention to watering and feeding. A free-draining soil with adequate aeration and fertility is imperative. Don’t use garden soil low in organic matter, which will dry out quickly and become compacted, depriving plant roots of oxygen. To keep perennials in planters happy I topdress yearly with screened compost mixed with granular organic fertilizer. Containers need watering daily, and at the height of summer even twice daily. To keep contained plants happy throughout the growing season, fertilize them well. This can be done simply by incorporating granular organic fertilizer into the growing mix or by applying liquid fertilizer regularly. Zipping around with a watering can full of liquid seaweed boosts fruit production, whereas liquid fish fertilizer aids in the production of leafy greens; both fertilizers give plants extra resistance to the stress of being grown in confined conditions. I liquid-feed plants weekly as they become established, and then every two to three weeks once they are growing well. Liquid seaweed is my secret to bumper yields of container-grown peppers and tomatoes.

Strip in the Garden! Strip diseased or disfigured leaves from the base of tomatoes, eggplants and peppers. Check the undersides of leaves for colonies of whitefly and aphids. Early removal prevents infestations later. Remove older leaves of beet greens, chards or perpetual spinach exhibiting leaf-miner or flea-beetle damage. Leaf-miners leave tunnels in the leaves; flea-beetle damage shows up as little round holes. Stripping these leaves early can prevent a buildup of pests in the vegetable garden. Discard or destroy the leaves – don’t add them to your compost.

Get a Leg Up on Floppy Plants Don’t throw away ruined pantyhose. Cut them into 2.5-cm (1-in.) stretchy strips, which grip and hold without cutting into soft plant tissues and are perfect for tying up perennials, annual vines, grapes, wisteria, climbing roses, tomatoes, eggplants, peppers and what have you. If you don’t wear pantyhose, no problem: buy bags of them cheap from any thrift store.

Carolyn Herriot owns The Garden Path Centre for Organic Gardening in Victoria ( and Seeds of Victoria. She is author of A Year On The Garden Path: A 52-Week Organic Gardening Guide.