Growing Urban Vegetables: A Toronto Master Gardeners Guide

Space is at a premium in our urban environment, but there can still be room to grow vegetables in containers or raised beds.  Gardeners should think about growing high value vegetables, and ones that taste best when they have just been picked!  This Garden Guide provides an intro to growing vegetables, with advice on where and what to grow.

Where to Grow – Vegetables need sun!

  • Most vegetables need at least 6 hours of sun. This includes all fruiting vegetables: beans, cucumbers, peppers, tomatoes, and zucchini.
  • Shade tolerant vegetables need 3-4 hours of sun. These are vegetables where we eat the roots or leaves. (beets, kale, lettuce, radishes, Swiss Chard)

Where to Grow Urban Vegetables – containers and raised beds:

  • Almost any vegetable can be grown in a container.
  • Almost anything can be used as a container but
    • Container must have enough depth and width for root system of vegetable.
    • Container must have drainage holes.
    • Container cannot have held a toxic substance in its previous life.
  • Use a soilless mix that is a blend containing at least 30% compost or composted manure as well as peat moss (or alternative) and some sand/vermiculite/perlite. Do not use garden soil, top soil, or triple mix in a container – these products will be too compacted.  Start with fresh growing medium each season.
  • Raised beds are an efficient use of space because they permit more intensive planting. Plants are reached from outside the bed, so no paths are needed, and compaction is avoided. This maintains better soil quality making it easier for plants to absorb nutrients and water.
  • Raised beds should be no more than 1.3m wide, assuming the bed is accessible from both sides.

Watering and Fertilizing:

  • Regular watering is required. Check for water by inserting your finger about 2cm down into the growing medium.  Water at the base of the plant and water deeply.
  • Feed your container grown vegetables because frequent watering will leach the nutrients out of the growing medium. Feed with an organic fish or seaweed based liquid fertilizer every two weeks.  Top dress with compost once a month.  Carrots and parsnips should only receive the compost.  Beans and root vegetables do not need to be fed.

Terms to Know:

  1. Days to maturity – from seed means the number of days from the time the seed germinates until the fruit is mature. On a seedling, the number of days from when the seedling is ready to put in the garden until the fruit is mature.  Not exact.  Can be found on seed packet.
  2. Hardening off – seedlings accustomed to the indoors must be gradually exposed to the outdoor elements before being transplanted into the This process should take place over about ten days to two weeks.  Initially, plants should be placed in a shaded and protected area for two or three hours a day.  Over the hardening period gradually increase the time the plants are exposed to the sun and wind each day.

Direct Sow Seed Outdoors or Start See Indoors and Transplant:

Many vegetables can be direct sown into the garden.  The following table gives dates for direct seeding in Toronto[1].  Plants that need more days to maturity should be started indoors and transplanted into the garden or can be bought as seedlings.   Seedlings need to be hardened off before they are transplanted into the garden. It’s a good idea to monitor the weather forecast before planting.  You can plant earlier if you will be around to cover your plants if there is a cold snap, and if your garden is small enough that you can cover the plants. Transplanting should be done on a overcast day if possible.

Category: Dates Vegetables
Frost hardy April 15 – 25 Lettuce, peas, radishes, spinach
Semi-frost hardy April 25 – May 10 Beets, carrots
Semi-frost tender May 15 – 25 Snap beans, tomatoes (transplant)
Frost tender May 25 – June 5 Transplant: cucumbers, peppers, squash

Choosing Varieties:

Miniature or bush type varieties are best for containers.  If you plan to eat your vegetables fresh (rather than freezing or canning) look for varieties that produce a harvest over an extended period of time.  Growing leafy greens as “cut and come again”, rather than growing into a full head, with frequent plantings over the season, will create a continuous supply.  Lettuce doesn’t do well in summer heat so consider planting in spring and then again in late August.  Swiss chard and spinach can supply summer salad needs.  Tomatoes come in “determinate” and “indeterminate” varieties.  Indeterminate tomatoes need to be pruned.  See the link below for instructions.

More information: