Sign In

Trending Searches: Job OpportunitiesParks | Library

Virginia Cooperative Extension
Natural Resources

Weather reminder: If Prince William County Schools close early or are closed due to inclement weather, classes and programs will be cancelled and will be rescheduled. Please call 703-792-7747 for more information.


Staff and volunteers with the Prince William Cooperative Extension’s Environment and Natural Resources program provide educational programs for individuals and business to implement sound practices producing aesthetically pleasing landscapes that have minimal negative impacts on the environment. Programs include:


Help us go green and save more than just a tree! For FREE lawn, landscape and garden updates, register to receive notifications by e-mail.

Seasonal Tips

The Environment and Natural Resources team and Master Gardener Volunteers of Virginia Cooperative Extension answer many questions throughout the year. Below are some of our most frequently asked questions for this time of year.

If you have additional questions, contact our Extension Horticultural Help Desk at 703-792-7747 or


With the mild winter and warmer temperatures we experienced in January and February, it appears we are 4-6 weeks ahead of normal bloom times.  As colder weather returns, plant growth will slow.  In the event of freezing weather, tender plants will need to be protected from the freezing temperatures.  Use burlap, sheets, or other covering to protect tender growth from low temps.  Remove it during the day to prevent breakage on Shrubs.  Resist temptation to plant tender annuals and vegetables earlier than April 20th which is our average frost free date.  Refer to the Recommended Planting Dates publication for more information


Time to put away the snow shovels and get out the lawn mower!  And now is the very best time to get your lawn mower blades sharpened.  Dull mower blades do significant damage to your grass plants so do your lawn a favor and get them sharpened (and beat the early spring rush for service).  If you didn't winterize your lawn mower last fall, now is a good time to prepare it for the upcoming season.  Operating any type of machinery can be hazardous so take a moment to read Safe Operation of Compact Tractors.

Crabgrass will begin to germinate as the temperature warm up so plan to apply your pre-emergent crabgrass preventer when the dogwoods are ready to bloom.  Find a crabgrass preventer product that does NOT contain fertilizer. 

If your lawn needs a spring overseeding, the best time to do it is between March 15 and April 15; otherwise you can wait until late August and the month of September.  

Spring is also a good time to take a soil test.  Soil test boxes and instructions can be obtained from the Extension Office (call 703-792-7747).  Test results will help you determine what your soil needs in order to grow a healthy lawn. 

It is not too late to participate in the BEST Lawns program.  For a $25 fee, we can measure and sample your lawn, develop a nutrient management plan tailored to your lawn and provide information to help improve the problems specific to your lawn.  For more information visit BEST Lawns on the Prince William County website.


Many insects are starting to appear in and around the house.  Virginia Tech has factsheets on many common insects.  Click here to visit the Web site or call our Horticultural Help Line for information on what's "bugging" you and the best and safest way to cure the problem.


If you have concerns about what to do if your trees and shrubs have sustained winter damage, click on our Managing Winter Injury document. 


While not complete, the following are diseases and insects that are more commonly found in our region. Contact the Extension office for help with diagnosis and control recommendations.

  • Boxwood blight is a recently introduced fungal disease that causes severe defoliation and decline of susceptible boxwood. It was first identified in Virginia in a nursery location in Carroll County in 2011, but has been found in both landscapes and nurseries in several Virginia counties since then. VCE and the Virginia Department of Agriculture and Consumer Services partnered to form the Virginia Boxwood Blight Task Force (VBBTF) to provide leadership to protect Virginia’s boxwood nursery industry, historical gardens and landscape plantings from boxwood blight. The task force is developing Best Management Practices (BMPs) for boxwood blight for stakeholders potentially affected by the disease (e.g. boxwood producers, retailers, boxwood tip producers, professional landscapers, historic groundskeepers and home growers of boxwood). The task force solicited valuable input on the BMPs from representatives of the various stakeholder groups through meetings and electronic communication. The BMPs are available for download in PDF format at the VBBTF website.
  • Anthracnose: A common spring fungal disease associated with wet weather.  Lesions are usually quite large and follow the veins of the leaf. It can also mimic cold damage.  Trees may drop some affected foliage. These diseases normally occur on large trees and do no permanent damage – practice good sanitation by cleaning up fallen leaves. You may choose to apply a preventive fungicide treatments next spring. A certified pesticide applicator and certified arborist can make these treatments for you. Plants susceptible: ash, maple, sycamore and oak trees.
  • Fireblight is caused by a bacteria. The most typical symptom is branch die back from the tip down typically resembling a shepherd’s crook. Affected branches usually start dying in mid-May or June. Prune out dead branches about a foot below the dead tissue. Sterilize pruning shears between cuts. Plants susceptible: cotoneaster, pyracantha, apples,and  pears.  
  • Juniper Tip Blight is characterized by dead branch tips in juniper plantings. Two different fungi cause this blight. Small outbreaks can be pruned out. Fungicides are also an option. The timing of the treatments depends on the causal fungus. Blight caused by Phomopsis is treated in the spring. Blight caused by Kabatina is treated in the fall.
  • Rose Rosette Disease: Believed to be caused by the recently identified Rose Rosette Virus, has been spreading through much of the wild rose population of the Midwestern, Southern, and Eastern United States for years. It has been confirmed in cultivated roses in Virginia and other states.  See link for more information
   Virginia Cooperative Extension
Environment and Natural Resources
8033 Ashton Ave. Suite 105
Manassas VA 20109
Virginia Cooperative Extension complies with the Americans with Disabilities Act. If you are a person with a disability and require auxiliary aids services or other accommodations for a workshop or meeting please discuss your accommodation needs at least five days prior to the event with Virginia Cooperative Extension 703-792-6289/TDD PC 1-800-828-1120.


You are now leaving the official Prince William County Government website.