They need 8 to 10 weeks to be big enough for plant sales so start them in the next day or two.

If they get too big just cut off the tops which will make them bushier and nicer looking.

Thanks! What size should I "expect" them to be at 8 weeks??

Thanks,
Beth

You could expect them to be 3-5" tall in that period, depending on the light intensity and variety.

One suggestion I can offer is that you plant shorter growing varieties first so that all of your plants will be relatively the same height for the market date. You didn't mention the varieties but there may be some short, bushy potting types like Spicy Globe that may not catch up in growth to a large leaf Italian type.

Slower growers tend to be Thai and purple types, especially Purple Ruffles. Cinnamon, licorice and lemon/lime basils are intermediate in growth. Standard basil varieties should be started a few weeks later for that reason but you can always clip plants as boulderbelt suggested.

How many plants per cell will you be using? When I did that 1 plant per cell looked skimpy and 2 per cell looked better, maybe that was because of my growing practices? Could anyone point me to some sort of industry norm for seeds per plug?

For many years I grew basil as a fundraiser for my church. It always out sold all the other herbs. I'm zone 6, and started 3/01.

Here is a link that might be useful: How I grew Basil from seed to Market Packs