Hi Mary Ann - you aren't killing them, just being overly kind to them. ;) The yellowing is typical of excess watering and the purple discoloration is quite common in seedlings grown in the artificial environment of inside. In other words, we all have it to some degree (as all the "why are my leaves purple?" posts at GW will attest.

It's cause is cooler temps than tomatoes prefer (something we can't really avoid), excess watering preventing the roots proper uptake of nutrients (let the plants dry out well before watering), and the fact that they are young.

Once transplanted to the garden and the warm weather stabilizes, it quickly disappears IF excess moisture levels are avoided and you don't get tons of rain.

So cut back on the water and cut yourself some slack with the worrying ;) and plant them in the garden as soon as it's possible. They will be fine.

Dave

For future reference: use only diluted fertilizers on seedlings - no more that 1/2 strength. 1/4 strength of the normal recommended mix is best. Seedlings cannot tolerate the regular dosage levels prescribed on the labels for full grown plants in the garden.

Thanks for your help, digdirt. The purple itself wasn't really bothering me, since I've read those posts you're talking about. :-> I've also had plants turn purple outside (and recover) when I set them out a little too early. But it's part of the whole picture, so worth mentioning.

Dang, I thought I was showing restraint with the watering. I've been letting the top of the soil get dry, usually every 7-8 days. Still too much? I could let it go a few more days and see what happens.

The fert I gave them is supposed to be the diluted strength already, according to what I'm reading. Well, I set my expectations low, and the plants are generally doing well, so I'm still ahead of the game.

MA