Home grown spinach is much better than any store bought in both taste and nutritional value. Plant around 20 seeds per foot of dirt for good measure. Then thin the plants out leaving three inches for each.
Seed Starting Advice,
Getting a head start on a growing season is a wonderful way to harvest earlier and harvest more per growing season. All you need is a seedling tray and some growing lights. Or you could stick the seedling tray filled with rich soil and your choice of seed by a well lit window. When its time to transplant your seedlings some plants like tomatoes need to be acclimated for about a week. Give the sprouts two to three hours of outside time a day to get used to conditions of wind and sun.