Winter Shrub Protection

Protect Shrubs From Winter Weather With Anti-Desiccant Treatments

Why?

Some broadleaf evergreens, such as Rhododendrons, Andromeda, Hollies, and Laurels are susceptible to winter injury from desiccation (also called winter burn).

All shrubs transpire (or give off water vapor) during the summer, but evergreens lose moisture during the winter too. This leaves them vulnerable to excessive moisture loss during the cold, wind, and dryness of winter.

The end result is that the evergreen leaves shrivel up, turn brown, and die. In severe cases, the entire shrub can die from desiccation.

Winter injury on holly after severe snow and cold

Holly with anti-desiccant winter protection

Shrubs Affected by Winter Burn

Shrubs that are most affected by winter desiccation are evergreens with broad leaves.

Some of the more common broadleaf evergreens in central New Jersey and eastern Pennsylvania include:

Andromeda (Pieris japonica)
Aucuba (Aucuba japonica)
Camellia (Camellia)
Euonymous or Wintercreeper (Euonymous spp.)
Firethorn (Pyracantha coccinea)
Gardenia (Gardenia spp.)
Hardy Boxwood (Buxus )
Heavenly Bamboo (Nandina domestica)
Holly (Ilex)
Leatherleaf Viburnum (Viburnum rhytidophyllum)
Leucothoe (Leucothoe)
Mahonia (Mahonia )
Mountain Laurel (Kalmia latifolia)
Privet (Ligustrum ovalifolium)
Rhododendron (Rhododendron spp.)

Some deciduous shrubs with sensitive stems, such as roses and hydrangea, can also benefit from anti-desiccant spray.

A few conifer species that are at the edge of their growing zone may also do better with protective treatments over the winter. These include certain species of:

Cedar
Juniper
Arborvitae
Pine, and
Cypress

If any of your shrubs have experienced winter desiccation in the past, talk with our Landscape Professionals about how to protect them this winter.

Anti-Desiccant Shrub Treatment

To minimize the chance of winter burn, Organic Plant Care uses an anti-desiccant spray, called Vapor Gard, to protect broadleaf evergreens and other winter-sensitive plants.

Vapor Gard is an organic, Pinolene®-based concentrate that's mixed with water and sprayed on plants. It forms a soft film that's flexible enough to allow the plant freedom of movement while limiting its water evapotranspiration.

Also called an anti-transpirant, this safe, non-toxic spray is applied in late fall before the weather gets too cold – usually in November. A second treatment can sometimes be applied in January if we have warm enough weather. If it looks like plants will need a second application of anti-desiccant, we keep an eye on the temperature and mobilize our crews when it looks like we’ll have a break in the weather.