Scapes are produced for the most part by hard neck varieties. They are firm, round seed stems that grow up from the middle of the garlic plant. They will produce a flower on top where the bulbils are found inside like little seeds. They can be stored in the refrigerator for quite some time. They add a much lighter element of garlic to dishes and are delicious to grill as well as to add into different recipes such as stir fries, grilled, or even made into a pesto for pasta.
Scapes usually form a month or so after the first leaves. They start off growing straight and then will start curving in circles. There are several different ways and opinions that people have about pulling scapes. Some say to pull them off before they curl as this is when they are most tender and the best to be eaten. Others say to leave them on until they start to curl the second time around, when you can snap them off and before they get so woody that you need a knife to cut them. The reasoning behind this is that it gives you a larger garlic bulb as the energy of the plant can then be funneled into growing the bulb and not growing the scape.
However a few people have the opinion to leave the scape on until it grows straight after curling. They say it does not affect the size of their bulb and it definitely increases the storage time. We pull ours after they have curled one to two times and have had excellent storage time. Our reasoning being is that we plant later and we also have very good bulb size already as well. If you leave your scape on, when it stands up straight that is usually a good indication that the garlic is ready to be harvested.