While an antler is growing, it is covered with velvet; the velvet contains the many veins and arteries that supply oxygen and nutrients to the growing bone. The growth starts at the tip, and is initially cartilage, and then mineralized to become bone. Once the antler has finished growing, the velvet is lost and the antler’s bone dies. This dead bone is the mature antler.
Fallow deer start to grow the antler almost immediately after they shed the previous year’s antler. The new antler then grows to it’s full size in about 6 to 8 months. You will hear people saying things like “they grow a new antler every year”, when actually, 4 t 6 months of that year it is either done growing, shedding its velvet (which takes two to three weeks) or they are in hard antler and not growing anymore.