Scrawny, Purple Tomato Seedlings

I'm on my third year of growing tomatoes from seed. The last two years everything went well and I grew strong, healthy beautiful tomato plants in peat pellets. This year, I read a lot of negative commentary about peat pellets and some great commentary about a particular kind of seed starting mix, so I thought that I would try this mix. I thought that I might get even better plants.  

Well, I should have left well enough alone. The tomato seedlings that I planted in the seed starting mix are puny and have a purple hue, while the seedling started in the left over peat pellets are thriving.

Look at the difference between tomatoes growing in the two different planting media.  The tomatoes on the left were started two weeks before the ones on the right in the seed starting mix while the plants on the right were started in peat pellets.

Close up of a seed mix seedling

A close up of the peat pot seedling

Last week, I added a small amount of organic Plant-Tone (a 5-3-3 balance) to the sickly looking seedlings. I figured that they probably had some sort of nutritional deficiency.  It doesn't seem to be making a difference, so I asked my neighbor (a landscape designer) what I should do.  She told me that the plants probably need phosphorus.  She only has synthetic fertilizers.  Does anyone out in the blogosphere have any suggestions for a good organic source of phosphorus?  I could try bone meal, but it is so slow acting.  Is there another source of organic phosphorus that is faster acting?  Is it worth trying to save these seedings, or should I just start some more plants from seed in the peat pellets?

I think that next year, I will go back to what has worked well for me in the past....