Janis Matson is a landscape designer and owner of Shoreline Landscape Design. She teaches workshops on gardening in small spaces.
Here are some of her tips:
1. Factors to consider - amount of light (for vegetables you want at least 4-6 hours a day), weight limitations, size of the balcony, wind exposure
2. What to plant - You don't want tall vegetables as they don't stand up to the wind. Consider trellises and patio tomatoes or other semi-dwarf varieties. Go for the bushy rather than leggy variety, below 2 feet so you don't need a lot of staking. You can plant just about anything, from cauliflower and broccoli to lettuces and kales. It's a question of space.
3. Drainage and soil - Drainage is a big issue, so think about soil type and containers. The water needs to drain out and not pool. For soil, you want to have a planter box mix, and add a compost especially if you're doing herbs or vegetables, about 50/50. There are all sorts of containers you can get at the garden store, or you can make your own out of coffee sacks (for potatoes), plastic bottles, and trays.
4. Vertical gardening is a good thing to consider - but only if you've got plants with a lot of drought tolerance and a shallow root system.
5. When to plant: The May 24 weekend is traditionally the time to get out and plant in the garden. Right now, you can seed inside.
Happy balcony gardening!