Holes in Skip Laurel Leaves: Causes and Solutions for This Common Problem

Skip laurel (Prunus laurocerasus) is a popular evergreen shrub used extensively in landscaping for its glossy foliage and fast growth habit. However, homeowners often notice holes developing in the leaves especially on lower branches. Known as shothole, this unsightly damage can diminish the ornamental value of skip laurel hedges and shrubs.

In this article, we’ll examine the common causes of shothole in skip laurel and effective treatment methods to restore plant health. With some adjustments to care and timely interventions, you can get your laurels looking lush again in no time.

What Causes Holes in Skip Laurel Leaves?

There are three primary culprits responsible for holes chewed into skip laurel foliage:

Fungal Leaf Spot Diseases

Several foliar fungal diseases can infect skip laurel, including cercospora leaf spot (Cercospora spp.), phytophthora leaf spot (Phytophthora spp), and anthracnose (Colletotrichum spp.). These fungi thrive in warm, humid conditions Infected leaves develop distinct spots that enlarge and coalesce, eventually turning brown and breaking down to create shothole symptoms.

Bacterial Leaf Spot

Xanthomonas arboricola pv. pruni, the bacterium that causes bacterial spot, is another possibility. Water-soaked lesions appear on leaves, becoming necrotic with yellowing halos. As with fungal diseases, the affected spots drop out to leave holes.

Environmental Stress

Abiotic factors like insufficient water, extreme temperatures, compacted soil, too much or too little light, and nutrient deficiencies stress the plant. Damage from these stresses can allow opportunistic fungal and bacterial infections to take hold, resulting in shothole damage.

In many cases, it’s the interaction of biotic pathogens and abiotic stresses that brings on shothole in skip laurels. Getting control of both factors is key.

How to Treat Shothole in Skip Laurel

If your laurel hedge is displaying early symptoms or isolated cases of shothole, take prompt action to get the problem in check:

• Improve air circulation and light penetration by selective pruning to open up the canopy. This reduces humidity levels unfavorable to fungal and bacterial diseases.

• Water at ground level instead of overhead to discourage wet foliage where pathogens thrive.

• Apply fungicide sprays containing chlorothalonil, myclobutanil, copper sulfate or Bacillus subtilis regularly as a protective barrier and at first sign of spots. Read all labels carefully and follow instructions.

• Boost plant vigor with a balanced 10-10-10 fertilizer to strengthen disease resistance. Fertilize in early spring and midsummer.

• Remove and dispose of fallen leaves and prune out any dead or obviously diseased branches. This limits spread of inoculum.

• For bacterial shothole, trim back well into healthy tissue, sterilizing pruners between each cut with isopropyl alcohol.

• Consider replacing susceptible varieties like ‘Zabeliana’ and ‘Herbergii’ with more disease-resistant cultivars like ‘Cherry Brandy’, ‘Schipkaensis’, and ‘Etna’.

If shothole damage is already extensive, more aggressive renewal pruning is needed:

• In spring before new growth begins, cut each stem back to just above a healthy bud. Remove and destroy all debris.

• As regrowth occurs, apply fertilizer and fungicides on a preventive schedule as described above.

• Be prepared to prune again next spring if needed, and then annually thereafter for maintenance.

• Keep plants well-watered during regrowth. Healthy, vigorous new foliage will replace damaged leaves.

Cultural Practices For Preventing Laurel Shothole

Once you’ve tackled existing shothole damage, focus on prevention so your efforts aren’t wasted:

Select a Sunnier Site

Skip laurels prefer morning sun with afternoon shade, rather than deep shade. Insufficient light leads to weaker growth vulnerable to pathogens and environmental stresses.

Space Properly

Do not plant skip laurels too close together. Allow at least 2-3 feet between shrubs for air movement, and 4-6 feet between hedge plants.

Improve Soil Drainage

Skip laurels need well-draining soil. Improve dense, compacted clay by amending with compost or peat moss to aerate and create a better growing environment.

Water Correctly

Allow soil to partially dry out between waterings. Overwatering encourages fungal and bacterial diseases. Drought stress also weakens plants, so aim for consistent soil moisture.

Apply Organic Mulch

2-3 inches of shredded bark or other organic mulch helps regulate soil temperature and moisture while suppressing weed competition.

Fertilize Annually

Feed with a balanced organic or slow-release fertilizer in early spring to maintain plant vigor and offset disease damage.

Monitor for Problems

Inspect skip laurel routinely. Early detection of spots or other abnormalities gives you the best chance of saving plants with prompt treatment.

Decrease Humidity

Improve airflow by thinning inner branches to open up shrub canopies. This keeps the humidity down inside the foliage, deterring fungal growth.

Remove Nearby Host Plants

Since fungal spores easily spread from one host to another, avoid planting other susceptible Prunus species like cherry laurel nearby.

Be Patient During Rehabilitation

Don’t expect an instant fix for existing shothole damage on your skip laurels. It takes time for the plants to generate new, healthy leaves to replace spotted ones that dropped out. But with persistence using cultural methods, fungicides, and proper pruning techniques, the shrubs will regain their former beauty. Just remember that prevention is easier than the cure!