Six weeks

April 13, 2024

Six weeks.  If you are starting veggie or flower seeds indoors, I recommend doing so six weeks before the last frost.

Most of us get the garden itch as early as February or March, but starting seeds too early will result in seedlings that are overgrown and stretched by the time they are ready to be transplanted into the garden.

Four weeks is also fine.  It is better to plant young and vibrant seedlings into the ground than plants that are past their best before date.

Tomatoes and peppers are the most popular crops to be planted in home gardens.  Sow seeds into seedling trays in the middle of April and if all goes well, they will be up in a week with two or three tiny leaves.  Two weeks later they will be an inch or two high, and by week 5 they will be 4 or 5 inches high and will be ready to plant in the garden.

Cabbage, cauliflower, kale and brussel sprouts, can be started earlier indoors, and because they don’t mind light frost, can be planted into the garden in early May.  Ditto for lettuce and spinach.

Melons, cucumbers, squash and pumpkins don’t like cold soil, and can be seeded 3 or 4 weeks before the frost-free date.  These vines sprout quickly and grow quickly.  They can also be seeded directly in the soil in late May or June, skipping the indoor sprouting step.

The advantages for starting seeds indoors rather than buying transplants are primarily two-fold.  Good garden retailers will have a broad selection of plants available for planting in springtime, but that selection will not be as vast as what is available on seed rack displays or at seed houses.  If you are fussy about varieties, you will want to buy and sow your own seeds.

Starting seeds indoors is cost effective.  A packet of seeds will cost about the same as a box of 4 or 6 transplants. Seeding trays and growing medium will cost pennies.

Seed packets will often give you far more seeds than is required for a backyard garden.  Use what you need and store the remainder in a cool dry spot for future use.  Many seeds will remain viable for several years.  Some will last decades.

When starting seeds, be sure to use a soilless growing medium.  For containers, use paper cups, egg cartons or last year’s plastic seeding trays.  Be sure to punch a hole in the containers to allow excess water to drain away.

When placing seeds in soil, a good rule of thumb is to plant them at a depth of 2 or 3  times the size of the seed.  Water carefully and slowly, so as not to cause disruption.  Allow excess water to drain.  For the first few days, and until the seeds are showing green, cover the seeding trays with a damp cloth or paper towel.  Lightly water to maintain moisture.  Bottom heat is beneficial.  Light is not necessary until leaves appear.

Once seeds have sprouted, provide lots of light.  If feasible, and if the weather is warm and mild, move the seedlings outside for some fresh air, but bring indoors if frost is expected.  Keep an eye on the weather and transplant seeds into the garden after the danger of frost is past.  For us in Southwestern Ontario, the frost-free date has traditionally been the Victoria Day weekend.