Today Jim re-potted the tomatoes into 4" pots. It has been just 20 days since we started the tomatoes in Bio Dome flats and as you can see they have developed a very healthy root system.
We are a strong believers in the Bio Dome system. It is easy and practically foolproof. I also think that bottom watering is the way to go. I think it is easier on the tiny seedlings and may reduce dampening off.
We use a 2 tray system to hold our seedling pots. The inner tray has an open mesh bottom and the outer tray is solid without drain holes. It holds eighteen 4" square pots. Water is added to the trays and absorbed through the drain holes in each pot. We use Black Gold seedling mix that seems to wick moisture very well.. With this system I only add water when the trays are dry but before the pots dry out. This worked very well last year and we shall see if it works again.