There are many different cell types and sub-types involved in the immune system. Some of the main types include: Lymphocytes: are white cells which circulate between blood and lymph. They play an important role in fighting infection.
After about 50 to 60 days, beets are ready to harvest. Not only can the roots be dug up and chopped to add flavor to a meal, but the greens of the beets can be harvested periodically and put in salads. Given how well these beets fare in different weather conditions, they can be grown several times in a summer.
Step 4: Harvesting the Beets. Beets can grow to baseball size, but for best taste, you want to harvest them when they are at golf ball size. You should also consult the package to see what the time to maturity is for the specific crop.