Juniper Care Tips

Types of Juniper:

Blue Atlas: 40-60’ x 30-40’
Canaerti: 620-50’ x 8-15’

Eastern Red Cedar: 35-40’ x 15-20’
Taylor: 30' x 3'

Saybrook Gold: 2-3' x 6'

The best time to plant junipers is in spring or fall, when moderate temperatures and ample rainfall support root establishment. Common junipers are low-maintenance,hardy shrubs that thrive in various conditions, including poor soils, dry areas, and urban environments with pollution. For optimal growth, provide them with moist, well-draining soil and plenty of sunlight. Juniper trees thrive in soil that is moderately acidic to slightly alkaline, with a pH range of 6.0 to 7.5.

When planting keep your soil type in mind if your soil needs to be amended do so. When planting make sure the root ball is above level ground by 2 inches to prevent root rot or fungus.

Fertilizing:

When planted in ideal conditions,junipers require minimal to no additional fertilizer. If needed, apply an all-purpose slow-release fertilizer in early spring. Follow the instructions to spread the fertilizer around the root zone and water thoroughly.

Pruning:

Junipers don’t need heavy pruning,but if shaping is necessary, they can be lightly pruned in late winter after the coldest weather has passed.

Sprayer Use:

• A pump-up sprayer is recommended.
• Avoid leaving chemicals in the sprayer after use.

Seasonal Adjustments:

• Reduce spraying during hot summer months following chemical instructions.

Watering Systems:

• Avoid overhead watering to minimize fungal leaf issues.
• Use drip irrigation as the best method for watering.

Tip Blight

Identify: Young growth is more susceptible to infection, while mature, darker green foliage remains resistant. Infected twigs initially turn pale, then reddish-brown, and eventually die, becoming brown.Scraping the bark reveals a clear boundary between dead, discolored wood and healthy tissue.Disease often develops during spring or summer growth flushes under warm, wet conditions.

Treatment: Inspect plants thoroughly, as symptoms of tip and twig blight may also result from drought, overwatering, or root damage. Choose disease-resistant varieties and plant them in well-drained, sunny locations with good air circulation. Avoid crowding, shaded areas, and sprinkler irrigation. Promptly remove diseased or browning branches. Pruning is usually sufficient for control,except in highly susceptible cultivars. If needed, apply fungicides such as mancozeb, thiophanate-methyl, or copper-based products before infection occurs. Always follow label instructions.

Bag Worm

Identify: Caterpillar feeding causes needle loss, slowing juniper growth during mild infestations and potentially killing plants during severe ones. Male moths are dark, hairy, with clear wings and a 1-inch wingspan, while yellow, maggot-likefemales lack wings. Larvae create carrot-shaped silk bags, which they carry as they feed.

Treatment: To prevent bagworm infestations, remove and destroy egg-filled bags in winter or early spring. For severe infestations or unreachable bags, apply Bacillus thuringiensis (Bt) insecticide in spring when young larvae are active, as they are more susceptible. Spray in late afternoon or early evening for best results. Other effective insecticides include spinosad, acephate, bifenthrin, cyhalothrin, and cyfluthrin, and always follow label instructions.

Spruce Spider Mite

Identify: Spider mites are significant pests of junipers, feeding on plant sap with piercing mouthparts. This causes yellow speckling on needles, browning, & needledrop. Heavy infestations may produce fine webbing, and prolonged damage can kill the plant. While most spider mites thrive in hot, dry conditions, spruce spider mites peak in spring and fall but decline in summer due to predator activity.

Treatment: Natural predators like predatory mites, ladybugs, and other insects often control mite populations. Avoid insecticides unless absolutely necessary, asit can kill these beneficial predators, potentially worsening mite issues. Miticides,designed specifically for mites, are less harmful to beneficial insects. Regularly spraying plants with strong water can reduce mites.To assess mite infestations,tap a branch over white paper and check for crawling mites. If dozens are present, damage is likely. Monitor populations every 7–10 days. For control, use insecticidal soap or horticultural oil sprays, following all label instructions.

Juniper Scale

Identify: Symptoms of juniper scale infestation resemble those of spruce spider mites. Affected plants may appear discolored, with needles turning yellow or brown and branches showing little growth or dying back. Severe infestations can kill the plant within 2–3 seasons. Look for tiny, 1/8-inch scales, often clustered on needle undersides, and shiny, sticky honeydew on infested needles.

Treatment: Apply horticultural oil as a dormant spray in late winter or early spring to suffocate adult females. For crawlers, use insecticides like acephate,malathion, bifenthrin, cyhalothrin, or cyfluthrin. Always follow label instruction sand precautions.

Cedar-Apple Rust

Identify: Apple cedar rust, caused by Gymnosporangium fungi, affects junipers,including Eastern red cedar, and requires an alternate host like apple or crabapple to complete its life cycle. The disease spreads between junipers and apples/crabapples and can be severe when these plants grow near each other. On junipers, hard brown galls form on branch tips in summer. After spring rains, these galls produce orange, gelatinous spore-filled tendrils that can travel up to half a mile to infect apple and crabapple trees. On apples, yellow spots develop on upper leaf surfaces, producing spores in late summer that can spread up to 2 miles to infect nearby junipers.

Treatment: Prune out all galls from junipers and avoid planting apple or crabapple trees near Eastern red cedars. If necessary, use a fungicide containing mancozeb or propiconazole for control.