Sterility and a high degree of aeration are generally considered two important properties of media to be used for starting seeds. Packaged seed starting mixes work well, (like Jiffy Mix) because they are sterilized, but they can be easy to over-water, so be careful if you use them.

I have found that sterility doesn't seem to be as important as aeration increases, probably because any chance of anaerobic conditions are reduced in an inverse relationship with aeration, so damping off disease pathogens don't as easily get a foothold as they can in heavier mixes like potting soil.

What I have used successfully: Jiffy Mix, 100% screened Turface, 100% perlite, the gritty mix, the 5:1:1 mix.

For the pine seeds, I would suggest spreading them over a bed of screened Turface or the gritty mix in the fall. Cover them with 1/4" of Turface fines or coarse sand and let them over-winter in your garage. If the seeds are stratified, skip the overwintering part & plant in early spring.

Since very high aeration levels are excellent for seed starting and seedling growth, it is often a benefit to cover the seeds with coarse sand or Turface fines to keep them from drying out on the media surface.

Al

I completely agree with Al.

Last February I sprouted Hot Pepper seeds in a course mix, most similar to the gritty 1:1:1.
Although I failed to sterilize my media (whoops!), I had full germination and no damping off.

I currently have an outdoor container of maple seeds in the 5:1:1 mix.

Josh

I lightly covered some tomato seeds in 5" pots of 5-1-1 mix on Jan 10. Put the pots on a heat mat and they all poked above surface on day 5 and 6.
5-1-1 seems to work fine with seeds. I got similar fast results with sweet pea seeds which I sowed last November to over-winter in a cold greenhouse.

I've started seeds and cuttings in the 5:1:1 mix with no problems so far, but I try to err on the side of caution when I offer any advice. I would feel horrible if you lost your seeds after I said the 5:1:1 mix was ok, even if I'm comfortable using it. Just watching out for you guys, is all.

Al

How about direct sowing ..

Would it work to put a thin layer of something on top of the soil, then the seeds and cover with fines? Say lettuce and onion for example. I have tons of pine bark fines, all the materials actually.

JoJo

Thanks for all of the information, greatly appreciated. I think that I'll do a little experimenting with the different soils.
Al, no worries.

Thanks again, Luke