On a related note, I'm copying my question from the seed propagation page: Can anyone identify if this leaf damage on my eggplant seedlings is a problem? To me, it looks like light damage from the t5 bulbs, but if it is an insect or disease problem, the sooner I know the better. thanks! http://www.flickr.com/photos/8698937@N02/8647323808/lightbox/

Have you fed them anything? Jiffy mix has zero nutrients. Give a boost with seedling fertilizer. Not seeing top-growth doesn't mean there's no growth. Right now your seedlings are developing root systems and those are far more important to a seedlings outcome than too much topgrowth wth nothing to support it below the soil. Outdoors you're still experiencing cool nights and the sunlight hours aren't long. You shouldn't be seeing a lot of topgrowth, that would be unatural. Patience is a virtue, don't rush the development of your seedlings.

1. don't use peat pots, generally, they are a pita and they dry out too easily and they don't decay fast enough when you set out the seedlings. 2. Adjust your temperature. Tomato seedlings are not at all happy in temps less than 60 degrees and do best at about 75 to 80 degrees. When the temperature is 60 or less on a regular basis, the plants cannot absorb potassium properly and develop purple stems and leaf undersides. 3. You may have a micronutrient deficiency. A photo would make it easier to tell. Just on general principles, please get a micronutrient supplement and give your seedlings an appropriate application. DarJones

What is the temperature where your seedlings are located? Purplish leaves often indicate a phosphorus deficiency which is often caused by cool soil temperatures. I've had this every year with my pepper and tomato seedlings, but they've always turned out OK once the weather warmed up.