Can you imagine what your 1/2 acre lawn would look like with 80,000 people per year walking through it or stopping to lay out a blanket for a picnic and some sun?  With that dense foot traffic, your soil would be compacted and cracked like the Liberty Bell!

This is what many popular public landscapes, such as the Independence National Historic Park (INHP) in Philadelphia, PA, endure every year. As you can imagine, it is a huge challenge to maintain healthy turf, as there is no down-time for rest and recovery to properly address the damage and stress created from the heavy use.  Most often maintenance treatments like weed killer, grass seed and fertilizer are applied in an ever losing battle to just keep turf alive.  We call this the “life support approach”, feeding the plant from the “top down” where one is just buying time until inevitably a major renovation is required. This is when Laurel Valley Soils gets the chance to address the landscape properly from the “bottom up” and fix the soil profile by amending it with compost.  Whereas healthy soil equals healthy turf, this approach is more like curing a disease vs just treating the symptoms.

Independence National Historic Park, located in the heart of Center City Philadelphia, is a 15.5 acre park which famously houses the Liberty Bell and attracts approximately 5 million visitors per year.  As the birthplace of our nation, it is imperative for the INHP grounds to be beautiful and welcoming to the people who travel there from all around the world.

Brightview, the largest landscape contractor in North America, has been providing the ongoing maintenance for INHP.  Last year, they reached out to the National Parks Service with a very bold proposal.  Knowing that the maintenance they were performing on a limited budget was not providing the results the landscape deserved, they proposed doing a full “bottom up” renovation and offered to provide this service pro-bono.

Of course the Parks Service said yes!  Brightview then approached their network of suppliers to join them in donating products and services for this project. When Laurel Valley Soils got the call from Brightview’s Scott Chambers, INHP Project Manager, to invite us to be part of such an important project, we were thrilled and happily donated several loads of compost.

Brightview got right to work removing the stressed turf and extra soil.  Then they brought in 100 yards of LVS Premium Compost and tilled that into the remaining onsite soil.  This both aerated the soil to relieve compaction and increased the organic matter content at the same time.  Then they installed a new irrigation system and laid sod after the final grading.

Healthy soils have a well-balanced structural matrix with organic matter providing the glue that creates good aggregation.  Well aggregated soils provide pore space for oxygen, biology and drainage.  Good aggregation also improves the ability to resist erosion and compaction, while increasing the ability to store water and nutrients and promote deep penetrating root growth.

Soil’s macro pores should have a ratio of 60% water and 40% oxygen.  We all know that plants need water to survive.  But just as importantly, oxygen is required for root systems and soil microbes to be able to breathe. The organic matter supplied from the compost helps aggregate the finest soil particles such as silt and clay into larger soil particles called “soil peds”.  These soil peds are what build a good structural matrix that provide pore space/aggregation.  A helpful visual is to think of a jar of marbles.  The marbles will have void spaces between them.  Even when pressure is applied on these marbles, the matrix resists compaction maintaining the voids. Poorly aggregated soils that lack pore space will see compaction quickly set in and the water to oxygen balance break down.  Dense compacted soils will quickly flip flop from being water logged to being dried out. Additional, equally important benefits provided by compost are slow release micro and macro nutrients that will continue to feed plants for years after only one application.  These nutrients are organic based and safe for our children, pets and environment.  And let’s not forget the biology which compost provides to the soil.  Think of healthy soil biology as a natural immune system for soil that helps it fight off turf and plant disease.

During the dedication ceremony and official reopening of Independence Hall National Historic Park, we asked Scott Chambers what his biggest challenge was with this project.  Without missing a beat, he exclaimed “Mowing it!  We’ve had to mow three times already this week!”  Now that’s a challenge we think anyone would be happy to accept!

Watch a video of the project below: