How to Care for & Feed a Blue Rug Juniper

Examine the location of the blue rug juniper while it is still small enough to transplant easily. This plant prefers full sun exposure, but tolerates some shade, where it grows fewer needles. Make sure the site has well-draining soil. This shrub adapts to most soil types, except wet soil. If using several of these plants as a ground cover, they need to be spaced about 5 feet apart.

Feed the blue rug juniper once a year in the fall with rhododendron-type fertilizer like slow-release 12-4-8. Sprinkle 1/4 to 1 1/2 cups of fertilizer around the base of the shrub, spreading it beyond the ends of the branches. Do not get the granules on the branches or trunk. The amount used depends on the size of the juniper. Small ones only need a little, while full-sized bushes need the maximum amount. Scratch the fertilizer into the top inch of soil with a rake and water the area well.

Water the juniper to the depth of 12 inches every 10 days for the first summer after planting. This encourages the growth of deep, drought-resistant roots. Do not keep the soil wet, since this causes root rot. If it rains, do not water the plant right away. Once established, do not water the juniper unless a prolonged drought occurs.

Spread 2 to 3 inches of organic mulch around the base of the shrubs until the shrubs fill in the area with a dense mat. Mulching reduces competition from weeds and keeps the moisture in the soil. Use chopped leaves, wood chips or dried grass clippings. Keep the mulch 6 inches away from the trunk and replace every year in the spring.

Prune back the branches with pruners when they begin to extend out of their growing area, for example into the lawn or adjoining flower bed. Cut the branches in late winter or early spring before new growth begins. To encourage new growth, pinch back new tips halfway. The juniper responds by growing more branches to produce a bushier plant. Do not cut into the old growth, because it does not grow back like the new growth.

Inspect the shrub for aphids and spider mites each month during the summer. Spray the needles with a strong stream of water to knock the garden pests off the branches. Bagworms sometimes infest blue rug junipers. Pick the caterpillars off the branches and drop them in a jar of soapy water to drown. Remove the webs, which contain egg sacks, and destroy them.