Tips for Balcony Gardening in a Cold Climate

Yes! Absolutely! You can have a garden on your balcony. As with any garden, there are some considerations and decisions to make. This year we are adding some planters to our product catalog, especially for you balcony gardeners. This blog post provides some advice for the practical decisions you'll be making as you design your garden. There is a separate blog article about the actual plants.

Containers

Of course, on your balcony, you'll need to use containers. Really, anything that can hold soil, and can drain water, will work. I advise you to get fewer bigger planters rather than many small ones. It will be much easier to keep them watered. Think of several plants in each planter. A planter needs to be about 45cm in diameter for most perennials to overwinter. Also, consider the winter hardiness of your planter. The double walled planters come with a winter warranty: Madison, Delano, Orinoco, Gramercy. The others we carry are also meant for outdoors, but we advise winter protection. The most reliable method would be to remove the soil from the planter every fall - but this is complicated if you have perennials planted in there. The solution is to use a liner inside your planter. Then you can lift out the liner in the fall, and store your planter for winter. I have found planter bags are inexpensive and work really well (so long as the pot is an appropriate shape). Check out the grow bags from Rootpro (www.rootpro.ca) , a local company in Thorndale. For the winter treat your planter bag similarly to a pot and wrap it in insulation. If a big planter isn't in your budget - yes, you can just use the bag. Spend your money on good soil and wonderful plants!

Understand your micro climate.

Your micro climate is the climate in your own little space. It may be quite different from what we think of as the climate that we live in. So, it's best to take a bit of time to consider the specific conditions for your plants. In my experience, this is the biggest factor in the success of a balcony garden. Does your balcony get blazing sun all day long because you are high up above any trees and face South? Or does it never get any direct sunlight at all because you are on the North side of the building? Is that sunlight going to be different in the specific location for your plants? Is there furniture or railings blocking the light. Is there a tree that will leaf out at the end of May? Is your balcony situated so that it gets sunlight but only for a shorter part of the season once the sun migrates further North. (OK, I know, technically, the sun isn't the one migrating...). Generally we consider less than 4 hours of sun a day to be full shade, 4-6 hours to be part sun, and more than 6 hours to be full sun. In addition, the length of your sunny season can influence what climate zone you are in. A longer season may shift you up a zone, and a shorter season may shift you down a zone. If you are above the fifth floor, your balcony likely has considerably higher winds than lower down. Compared to gardening in the ground, this wind can affect your plants in many ways. More wind will mean more evaporation. The solution is to make sure to water frequently. The wind may be so much that tall plants could break. The obvious solution is to grow shorter plants, but also if your plant grows up in this windy location it will likely be stronger. For instance, I grow papyrus grass on my deck. Usually the existing growth that is there when I transplant them in the spring will break in the first thunderstorm, but the new branches that grow in place are fine. The wind may even be so much that your pots could tip over. You can choose a shorter wider pot, or put something heavy in the bottom, or even secure it to something that doesn't move.

Dealing with Winter

Compared to being in the ground, plants in pots experience more winter stress. The problem isn't that they get colder. Here in Toronto our ground generally freezes quite solidly for most of the winter. The problem is that they may freeze and then thaw over and over. The best solution to alleviate that problem is to provide as much insulation for your pots as you can. For rectangular pots, before any soil is added, line them with pink styrofoam insulation (like builders use in walls!). If that won't work, try to keep all your pots close together for winter, and consider wrapping them in bubble wrap or some other insulation. If you have a windier location, that will also affect your winder hardiness. Any plants that are exposed to winter winds will have a tougher time on a higher balcony. You may need to provide a wind shield, or move your pots to the least windy part of your balcony.
My usual advice is to consider your hardiness zone to be 2 zones colder than the one that you live in. For Toronto, choose zone 4 and colder plants.

Soil

DO NOT, for any misguided reason, use garden soil in your planters. It WILL become compacted, it will not drain properly, and your plants will suffer. Plant roots need air, and in a compacted soil they just don't get any. Besides, garden soil is just SO heavy. It's more expensive, and a bit of an investment, but get a soilless mix designed for planters. It will contain either perlite or vermiculite that makes sure that there is air for the roots of your plants. There are different brands, and people have their preferences, but I will point out that PROMIX is a Canadian company based in Quebec. Usually these mixes contain enough fertilizer for a season. For subsequent years you can replace a portion of the soil, and start using a diluted fertilizer.

Watering

One downside of planter soils is getting them wet enough in the first place. Usually they have quite a bit of peat moss in them, and tend to be hydrophobic when they are dry. Use warm water to get them wet before planting, and NEVER EVER let them dry out. Planters need to be watered often, sometimes daily. If you have the opportunity, I do recommend an irrigation system for your planters. If not, plan to water daily when you go out to admire your garden's progress.

What to plant?

That's a topic for a separate article. Or, you can take a look at our collection of planter friendly plants.