The blackberry plant is a woody shrub that grows wild and is commonly found throughout North America. There are also cultivated varieties that are grown for their rich, sweet, slightly tart fruit, which can be picked and eaten raw, canned as jams, jellies or preserves, or used in cooking in pies, pastries and other confections. There are several species of blackberry with different names including dewberry, boysenberry, thimbleberry, and strawberry-leaved raspberry, though raspberries are actually a different plant.
Blackberries grow in every state within the continental United States and all of Canada. They inhabit woodlands, thickets, meadows and abandoned pastures and are frequently seen along fences, trails, railroad lines and roadsides. The plant prefers moister soils, however it can grow in drier conditions. Blackberry plants grow best in fertile soil with a lot of organic material, although they can tolerate clay and rock soils.
Blackberry plants produce long stems referred to as canes that grow in large brambles. There are two types of blackberry plants. Those that produce produce long, arching stems that are self-supporting can reach up to 10 feet tall. Others that cannot support themselves trail along the ground. The canes are green and usually bear thorns along them, although there are thornless varieties. Canes are biennial, which means they grow one year and flower and bear fruit the next. The first year's growth is referred to as a primocane, and the flowering growth, the floricane. Once the cane has borne fruit, it will die back, and new canes will take its place.
The leaves of the plant alternate on either side of the canes. They are compound leaves, each consisting of three to five leaflets. The leaflets are oval in shape with a pointed end. They are deeply veined, with serrated edges, and a prickly feel. Leaflets are green on the surface, and the underside is light green.
The flowers of blackberry plants form in clusters along the canes. Each flower is about 3/4 of an inch across and is simple in form. A whorl of five white, open, oval petals that are often a little wrinkled in appearance, is attached to the sepal, or base of the flower, with a spray of anthers emanating from the center. There is little or no fragrance.
Red and hard when immature, the fruit of the blackberry ripens to a dark purple color. The berries grow in clusters on short stems. Each berry is an aggregate fruit, composed of a bunch of smaller fruits called drupes. Each drupe, in turn, has one seed. The surface of each drupe is smooth and glossy with a fragile skin. The center of the berry has a core that the drupes are attached to. This core helps differentiate blackberries from raspberries. The center of a raspberry fruit is hollow.