early cold treatment, anyone?

[johno]

Tomato growers: How many of you do an early cold treatment of your seedlings? I have meant to try this for the past few years. This year I finally remembered about it early enough to try it. It says you need to start them 10 - 14 days earlier if you do this. See Tip number 1:

http://www.kdcomm.net/~tomato/Tomato/start.html

Tip 1 - subject the seedlings to a cold treatment: 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.