There are around 500 species of barberry (Berberis) bushes, according to the Encyclopedia Britannica. Some are evergreen, while others are deciduous. All of these thorny but eye-catching plants are extremely hardy. Barberry tolerates very poor growing conditions and requires only minimum care, making them a favorite choice for many home gardeners, especially those that live in rocky soil and extreme climates, such as in southern parts of the United States.
Barberry bushes grow best in at least partial sun, but will thrive in full sun except in the hottest climates. Six hours is the minimum amount, with eight or even 12 hours preferable. Gardeners living in tropical or subtropical areas should plant barberry bushes where they will receive morning sunlight followed by filtered or dappled afternoon shade.
Barberry bushes are known for their ability to perform in even the poorest soils. They grow any type of soil--clay, sandy, rocky, loamy--except very boggy or wet soils. If the area is covered with standing water for part of the year, perhaps due to flooding, the barberry bush probably will become infected with root rot, a fungal disease that kills the roots of the plant. Bayberry will also not perform well in salty soil, because they are sensitive to salt.
Newly planted barberries should be watered deeply and thoroughly after planting and throughout the first growing season. Established plants need little water and can tolerate drought conditions. Still, barberry bushes will benefit from regular watering in prolonged hot, dry conditions.
Barberry bushes planted in the ground do not need fertilizing except after heavy pruning in the spring. Potted barberry, however, can benefit from the application of fertilizer. Do not use a fertilizer in granule form, because these often contain salt. Apply a liquid fertilizer in place of a regular watering once a month. Use one formulated for potted evergreen or deciduous plants, depending on the species and variety of your barberry.
Barberries should not be pruned often, unless they are grown as a formal hedge. If a barberry bush becomes overgrown, however, horticulturists with Clemson University suggest pruning it back severely--to only 1 foot above the ground--in late winter, then following that up with an application of fertilizer in the spring to encourage new growth.