Buy Deer Berry at Trees-Plants. Buy Deer Berry at Trees-Plants. The Deer Berry bush has begun to grow in popularity over the past years. This bush does not have any major pests that bother it. Most of the Deer Berry bushes grow to a mature height of about 15 feet and 10 feet wide. These bushes reach maturity at about 10 years, the fruits are found in the top of the bush on shoots which grew the year before. The berries have a typical berry shape, a delicious taste and great sugar content.