Growing tomatoes

When to plant tomatoes

TomatoThe growing season in most of Alberta is about four months (mid May to  mid September) so tomato gardeners usually give their plants a head start indoors. Starting the seeds in March should allow enough time for seedlings to be garden-ready by mid-May. If you plant early, keep an eye on the overnight low temperatures just to be safe — if the forecast is for near freezing temps, cover your tomato plants at night. (more on starting tomatoes from seed)

The best soil for tomatoes

Tomatoes do well in slightly acidic soils, that’s standard for most garden veggies but almost any soil can be amended for tomatoes fairly easily!

You don’t want soil that’s extra sandy, it will drain too quickly; and soil that’s too heavy with clay will take too long to drain. Adding organic matter such as leaves, grass clippings and compost will improve the drainage quality of the soil making it perfect for your tomato plants. The roots need an ongoing water supply but don’t over-water, they won’t do well in a saturated environment.

Gardens should be replenished with organic matter every season to enhance soil quality and provide it with  nutrients and microorganisms that the roots require for healthy plants.

Preparing soil for planting

Tomato SeedlingsWhen you’re ready to plant your tomato seedlings, loosen the soil (with tiller or garden fork) as you work in organic matter and remove weeds, to a depth of about eight inches.


Make a trench about eight inches deep for your plants but before placing them, add a thin layer of fertilizer into your trench, either 5-10-10, compost, or prepared dehydrated animal manure (more about fertilizers here).

Cover the layer of fertilizer with a couple inches of soil and then place your seedlings to a depth of 3 or 4 inches. It’s important that the roots are not in direct contact with fertilizer as the salts will dehydrate them, but near enough that they’ll absorb nutrients from the fertilizer in the soil as they grow. If you mix compost into the soil there’s no worry about plant roots becoming dehydrated. Lightly press soil around the base of your seedlings so they stand upright, then water and wait!

Tomato plants will take anywhere from 45 days to three months to mature, depending upon the cultivars you choose. Seed packets generally give the estimated time to maturity.

Top 10 benefits of adding compost:

  • gives structure to the soil and helps deter erosion
  • improves drainage quality of soil high in clay
  • helps aerate soil naturally and prevents it from becoming compacted
  • helps sandy soil retain moisture
  • attracts earthworms!
  • enriches soil with nutrients
  • incorporates organic matter (that plants love!) into soil
  • releases nutrients slowly
  • improves soil structure
  • helps deter soil-borne pests and diseases

Reference: Composting for Dummies

Methods of growing tomatoes

Staking tomatoes

The traditional method of pounding stakes into the ground and tying the plants to the stakes is a lot of work upfront but probably the least amount of work in the long run. Self-supporting and spiral cages also provide support for young plants but depending on their strength they may need to be replaced by sturdier cages or stakes once the tomatoes are heavy on their vines. Check your plants daily to be sure that vines are tied securely enough that they don’t allow fruit to droop to the ground but are loose enough that the ties don’t cut into the plant stems.

Staked Tomato Tomato in cage

Growing tomatoes in hanging baskets

One of my favorite ways of growing tomatoes is in hanging baskets, cherry tomatoes are particularly beautiful and work well as hanging plants. Upside down is a variation on the hanging basket — the plants grow out the bottom of the planter straight down, eliminating the need to stake or cage, gravity does the work!  Yards where growing space is limited, and balconies with lots of sun are perfect for both the upside-down planter and the hanging basket method.


Growing tomatoes on a trellis or strings

Another excellent option for the small garden is to grow tomatoes on a trellis or strings. To start, secure a string to the tomato plant at its base and the other end to an overhead crossbar — or as shown in the diagram below. The vine should be trained to the string as it matures and like with stakes, plants need to be checked regularly that they are not tied either too tightly or too loosely. The taut string should provide enough tension to support vines when they are in full bloom. Tomatoes are fairly easy to train and pruning is usually not necessary as additional lateral stems may also be easily trained up the strings.

Tomatoes on a trellis

No matter how tomatoes are propped, whether staked, caged or trained on string, it’s important that the fruit does not touch the ground, contact with the soil increases the chances of fungus and disease.

 Recommended tomato reading

The Complete Guide to Growing Tomatoes: A Complete Step-by-Step Guide Including Heirloom Tomatoes (Back-To-Basics Gardening)