I'm starting some lettuce from seed. I decided to use a different method this year and had some questions. I used cococoir and perlite in about 1 cm x 1cm squares. The seeds have come up and are about a cm tall with 2 small leaves. The plan is to move these 1 cm blocks into larger blocks but I'm not sure what to use. Do I add the 1cm blocks to larger blocks of cococoir and perlite or do I add to blocks of potting soil or some other medium? ThanX

To further explain my method I have a little hand tool that makes 1cmx1cm blocks and another tool that makes about 2 in x 2in with a hole the 1cm blocks fit in. You than place the 1cm blocks in the 2 in block to continue it's growth. Hope this makes sense.

Cococoir and perlite have no nutrients. As in, zero. So you can feed the seedlings with a complete fertilizer, and essentially grow them hydroponically in that stuff, or start to grow them in real soil. Commercial potting soil will have everything needed.

DougL said:Cococoir and perlite have no nutrients. As in, zero. So you can feed the seedlings with a complete fertilizer, and essentially grow them hydroponically in that stuff, or start to grow them in real soil. Commercial potting soil will have everything needed.

Thanks, that's what I was wondering, so the potting soil won't be too "strong" for the young plants?

What "strength" are you talking about? It's soil. Plants grow in soil. Many people germinate their seeds in potting soil. Seed starting mix is mainly potting soil that has a somewhat finer texture.

DougL said:Cococoir and perlite have no nutrients. As in, zero. So you can feed the seedlings with a complete fertilizer, and essentially grow them hydroponically in that stuff, or start to grow them in real soil. Commercial potting soil will have everything needed.

Thanks, that's what I was wondering, so the potting soil won't be too "strong" for the young plants?

DougL said:What "strength" are you talking about? It's soil. Plants grow in soil. Many people germinate their seeds in potting soil. Seed starting mix is mainly potting soil that has a somewhat finer texture.

I had read or heard somewhere not to use potting soil or too much compost as it "burns" the young plants. Not sure if it's an issue here but that is what I was referring too.

Certainly manure-based compost, and especially poorly composted manure-based compost can nitrogen burn plants, and seedlings are especially fragile plants. Also, poorly made potting soil may be somewhat acidic, from too much peat moss (though some potting soils are intentionally acidic, for ericaceous, or acid-loving plants). But commercial general purpose potting soil ought not to have those problems. Unless otherwise indicated, it will be neutral-ish pH.