Mahonia is the state flower of Oregon. It is sometimes called Oregon grape, Oregon holly or Oregon hollygrape. The leaves are like those of the Christmas holly plant. Flowers are yellow and form on the end of the twigs in April or May. When the flowers die off, clusters of fruit form that look like purple grapes. The fruit is edible but is so sour it's eaten more by birds than by humans. The plant will grow to an average of 7 feet tall and 5 feet wide and is hardy in USDA planting zones 5 through 9. Plant mahonia where it will receive morning sun and part afternoon shade.
Dig a hole three times the diameter and the same depth of the root ball, using the shovel. Clean the soil of all weeds, lawn grass and any other debris. Amend the soil with one part compost to three parts original soil.
Place the shrub in the planting hole and fill halfway with the amended soil. Place enough water in the hole to settle the soil around the root ball and remove air pockets. Continue to fill the hole until the soil is at the same level as the surrounding ground. Hand-tamp down firmly.
Water the shrub to keep the soil moist for the first two weeks after planting. For the rest of the growing season, water twice a week if there is no rain. Additional water may be needed during very hot, dry or windy weather.
Apply a time-release evergreen fertilizer in the spring each year, following the manufacturer's directions.
Prune to shape the tree after the fruit drops off, using pruning shears. This shrub has a very irregular growth habit and will look unkempt if not shaped. Cut off dead, damaged or diseased branches any time.