Starting Tomatoes from Seed

Growing your own plants from seed:

-allows one to be sure of variety

-gives one more choices of varieties

-can ensure less chance of disease, insects and weeds

-allows for special care or treatment

-raising seedlings for grafting

One can start your tomatoes begining 6-8 weeks before setting them out in just about any type of container that can provide drainage. Just make sure to start with good seed and a sterile soil mix. I like to use a half-peat moss, half-vermiculite mix. Using a sterile mix will reduce the potential for soil borne disease problems.

Pre-moisten the mix slightly before planting. Plant seed about 1/4" (7mm) deep, cover with soil and water.

Seed should emerge in about 3-5 days at a temperature of 75-80F/24-27C degrees(min 50F/10C max 95F/35C). Optiumum temperatures for growth are 65-80F/18-27C days and 60-65F/16-18C nights. During germination, place them on the top of a refrigerator near the back to act as a heating source. Wait till after the seeds have germinated to put them in light as some genotypes (or varieties) require dark for germination to occur.

Keep the soil moistened till germination. When the seedlings start growing, allow the soil surface to dry slightly between waterings. I gauge watering by lifting the containers to check how heavy they are. I try not to water past 3pm. If seedlings sit overnight in cool and wet it can increase the chance of a disease problem or mold. That said, never let the seedlings wilt. If one misses a watering during the day and finds they needing water late afternoon, go ahead and water them.

Wait till the first "true leaves" appear to fertilize with a mild or dilute fertilizer solution that is based on a higher phosphorus content (P=the second number of analysis). These are often called "Starter" or "bloom booster" fertilizers and will work well for this purpose. P helps in fruit and root growth but it's also been found that much of the P in the fruit is acquired early during seedling in growth. I suggest using 1/2 of what the label recommends. One can always fertilize more. This way there shouldn't be any problems.

To start seed:

• good seed
• clean containers
• sterile soil mix
• warm temperatures for germination (75F/24C)
• once they emerge a good light source

Tip 1

from Growing greenhouse tomatoes in soil and in soilless media Dr. A.P. Papadopoulos Research Centre Harrow, Ontario

Under a cold treatment regimen, place young tomato seedlings in a day and night air temperature of 50-55F/10-13C for approximately 2 weeks, while providing as much light as possible for 9-12 hours. Seedlings should be subjected to cold treatment just after the seed leaves (cotyledons) unfold and the first true leaves start to appear (see below). Shoots kept at low temperatures at this stage of growth produce a small number of leaves below the first flower cluster and therefore flower earlier; roots kept at low temperatures cause branched clusters, i.e., many flowers in the first and possibly the second cluster. Cold temperatures during both day and night are effective.

stages in seedling growth used for initiating (plant A) and terminating (plant B) the cold treatments

The cold treatment increases the number of flowers but does not influence the setting of fruit. If later conditions for fruit setting are right, a greater number of flowers will set fruit because of the increased number of blossoms. If, however, the temperature for fruit set remains less than ideal, the pollen does not germinate and grow normally, resulting in poor fruit set and cat-faced fruit. When the cold treatment is used, seed 10-14 days earlier than usual to compensate for the slow growth rate during the cold treatment. The growth medium in the seedling trays must be sterile, because when plants are grown at relatively low temperature the danger of damping-off is increased.

Tip 2

Leggy plants can result from poor light, excessive watering, high nitrogen, warm temps or combinations of them. Cooler temperatures can slow plant growth down as well as cutting back on water and fertilizer. Light can be supplemented with flourescent shop lamps. If the plants are leggy when you plant thats, okay, just carefully burry the stem into the soil and roots will form along it.