I've got to get some carrots in the ground pretty soon or they won't be ready when I need them. You can direct seed them in the soil right now and because of the cold weather some of them won't come up. This seed pack is 5 years old. Maybe some of the seeds are no longer viable. The ones that aren't certainly wouldn't grow, but how do you know what seeds are good and which aren't?
Sprouting is one of the easiest ways to figure that out. Just take your seeds and place them on a dampened paper towel. Lightly spray the seeds, close them up in a zip lock bag and place it in a room. Some will put them in the furnace room. I just put them in an upstairs bedroom. In the case of these carrots you can see they germinated in 4 days. However, one of them didn't. Whichever seeds sprout are the ones that are good seeds. These then go into a growing medium where they will sit for the next 80-90 days. By that time they'll be delicious mini-carrots that are full of flavor. If I had planted these directly it would have taken 3-4 weeks before they emerged in the garden soil.
I just cut off about 25 days by doing it this way. And I know what seeds are good to be transplanted to individual cells. And since I know I need about 100 carrots, I'll sprout 115 on paper towels. This gives me some wiggle room. Then at a certain point they will go into the garden and take up a measly 4 squares. No wasting time, money, space, or seeds in the square foot gardening system. You only plant what you eat.
For the local folks, in a matter of a couple of weeks I'll be posting dates for SFG classes. Some are free, some aren't. The free classes cover the basics of the SFG system. The paid version($25 per person)teach not only the basics but also the advanced techniques of the system.