One of the toughest plants in the landscape, junipers (Juniperus spp.) are very hardy and tolerant of drought. They grow in USDA zones 4 through 8, depending on the variety. Juniper plants are either male or female. The male produces flowers and the female produces berries, which are used to flavor the alcoholic spirit gin.
An evergreen with pointed, sharp, scalelike foliage, junipers produce fleshy blue berries that can take up to two years to mature. Juniper leaves take on colors in varying shades of green, from pure green to yellow-green to blue-green. Their foliage can also be yellow, gold or blue.
Plant junipers in full sun and well-drained soil. The are well-adapted to hot, dry and unimproved soil and thrive where other evergreens will not. Do not plant junipers in shade because they will grow thin and be more susceptible to diseases. Many varieties will grow in sand and several are tolerant of salt spray. Because of the large number of varieties, junipers can be planted virtually anywhere in the landscape. They make excellent hedges, windbreaks, screens, ground covers, foundation plants or lawn specimens.
Hundreds of varieties of juniper exist, according to the University of Missouri Extension. Many named varieties have been confused with other varieties and a certain amount of confusion exists when identifying them. They can, however, be divided into three major groups: upright, prostrate and spreading. Upright junipers are commonly grown as shrubs and are often heavily sheared to contain their size. Most upright junipers have foliage that is blue to blue-green. Prostrate juniper varieties are used as ground covers. They grow about 18 inches high and spread over a large area. Their foliage color ranges from light green to gray-green to blue-green. Spreading juniper grows in either a horizontal or arching habit, growing from 2 to 8 feet high and spreading from 5 to 8 feet. Spreading juniper ranges in color from yellow-green to green to blue-green.
Care and Culture
Junipers require very little care from the home gardener. They should not be irrigated other than normal rainfall and do not tolerate over-watering. Fertilize them in early spring and late summer with a complete, balanced granulated fertilizer applied at the rate of 1/2 lb. for every 100 square feet of growing bed. Do not allow the fertilizer to come in contact with the base of the plant. Apply fertilizer prior to a rainstorm or water it in with a soaker hose.
Pests and Diseases
Junipers almost never succumb to disease, except when over-watered or planted in shade. They are susceptible to insect pests, including spider mites, leaf miner, scale and aphids. Control these insects by applying pesticide recommended for the control of the individual pest, following the directions of the pesticide manufacturer.