Well it's taken out of context from a current discussion on the Growing from Seed forum so you have to know the context of the whole discussion but no, it isn't an old wives tale or such.

Seed starting mixes are just that - germination mixes only, not growing mixes - and most do not contain any sort of fertilizers because it isn't needed and can be detrimental to both germination rates and young seedlings regardless of the type of fertilizer it is in the mix although some types more so depending on its concentration.

Yes, fertilizers in the mix MAY burn young seedlings. So yes they may very well be considered "detrimental". This point has been often discussed here and it applies to ANY seedlings. For that reason, as well as the extra cost involved in using fert- plus mixes, professional growers do not use mixes with fertilizers in them.

However, the need to avoid using them also depends on your goals and how you grow your seedlings. For a few seedlings and a desire for convenience some use fert-plus mixes. Fine, their choice. They prefer to avoid having to pot up seedlings. EX: Wintersowers use it because the intent is to leave the plants in that WS container to garden time.

But nurseries or growers that use plug trays or germination flats and grow huge numbers of plants wouldn't use one because you can't quick-load the trays with it (way too coarse), it is an extra expense that isn't needed, it can affect germination rates and kill young seedlings, and they know the benefits for the plants to transplanting potting up. Their goal is quality not convenience.

So in context: as was being discussed on the G from S forum, a newbie wanted to buy a seed starting mix without ferts and only realized when they got home that this one had it. Question was "should I still use it"?

If you are happy with your results - great. Otherwise try both a with and a without and see which works best for you.

Dave

I WS all my seeds in miracle-grow soil. If you go over to the WS forum and ask what all of them use you're gonna get the same answer. It's so mild that it causes no harm and if you can't get around to transplanting immediately you don't have to concern yourself with feeding the seedlings. It removes that aggravation and worry.

IMHO, it's a wonderful sowing medium, I don't know if there is an organic version, I suppose that might be important to some people, but otherwise use it with confidance.

Wen I first began to grow my own from seeds, I followed the advise of those who had been growing for a lot longer than I. I used non-fertilized sowing medium. After about five years, I forgot to buy the medium and all I had was the slow release fertilized soilless mix. I bit the bullet and used what I had. My germination rates and plant success rate was about the same as before. Since then I have only used mix with fertilizer as starter and transplant medium with no or little adverse effect.

My observation is that starter is finer. Regular is courser, so you have to be careful to get rid of the big chunks. Tomatoes grow in lots of stuff. Use what you are comfortable with.

Dave, you did a nice job of answering my question. Thanks.
I think what we get into is what the professional and experts do to get the most. Where common beginners would not even notice the difference.
What bothers me is when a new person, who is afraid to try, asks a question and is told that they need this or that to germinate and ever which brand, and then they need this or that to grow the seedling. And which light they have to have, and oh yes, which container is needed.
Wouldn't it be much better to say "that will work, but it would be better if you did such and such? Rather than scare them off. Gosh, when a kid we would grab an old tomato can with dirt from the garden, put it in the window and the tomatoes seemed to taste better than they do now.
If I sound harsh, I don't intent to. Its a nasty cold day and I want to plant some tomatoes.

Trudi: I have started tomatoes in MG potting mix, potted in MG and grown in container with MG, Added a little liquid fertilizer later in the year, which I don't think was really needed. Course if I was an expert, I would have done a hundred other thing to make them grow better.
Kenny

What bothers me is when a new person, who is afraid to try, asks a question and is told that they need this or that to germinate and ever which brand, and then they need this or that to grow the seedling. And which light they have to have, and oh yes, which container is needed.
Wouldn't it be much better to say "that will work, but it would be better if you did such and such? Rather than scare them off.

I agree completely. But keep in mind that some of the "scare them off" is due to limitations of this medium. It gets misinterpreted easily. Some of it is folks that are just way too easily scared off or affronted. And some is due to trying hard, maybe too hard sometimes, to give them the info that will insure them the best chance at success.

Sure I could say "just grab an old tomato can with dirt from the garden, put it in the window and the tomato will grow fine" but that sure would stack the odds against them. ;)

So I'd prefer to say for the best chance of success:
(1)Pre-wet a fine grained soil-less seed starting mix that contains no fertilizers in it. Germinate your seeds in small 2" shallow plastic containers over a source of heat. Mix is available wherever seed starting supplies are sold.

(2)Once they break the surface of the soil, move them immediately under a strong source of fluorescent light for at least 16 hours a day.

(3)Above all do not over-water, allow the surface of the soil to dry to the touch between waterings.

(4)Insure a good supply of fresh air circulation and air temperatures no higher than 65 degrees if possible.

(5)Once the first set of true leaves develop, deeply transplant those seedlings into approx. 4" dia. containers filled with a quality soil-less growing mix that either contains some added nutrients/ferts or plan to feed weekly with a 1/2 strength diluted liquid fertilizer solution.

They can take that, use what they want, and adjust as their circumstances dictate. But if that info scares folks off from trying to grow their own tomatoes from seed than maybe they need to stick with buying transplants.

OK?

Dave