By Matt Keenan - Owner, Renew-a-lawn
Some front lawns are being converted into gardens, and I fully support it.
It would make sense to think that yard gardens would put the lawn care industry in jeopardy
but yard gardens aren’t replacing our lawns any time soon. Lawns remain popular with homeowners who feel they don’t have time to maintain garden space. However, an increasing number of Kingston residents want to know if they can maintain them sustainably.
While the “no mow May trend” is gaining popularity, In June, uncut lawns will require petrol-powered mowers and trimmers and have the clippings be taken offsite (usually), contributing to the GHG emissions that will exist in our atmosphere for centuries. No mow July or August as an alternative can still be mowed with little effort a month following and will still provide flowering weeds such as clover and chicory.
Why lawns get a bad wrap (and shouldn’t)
The ecological utility of lawns are often taken for granted. Lawns can play an important role in evaporative cooling, noise reduction, carbon sequestration, air purification and managing water runoff to name a few.
CHEMICALS IN ONTARIO
The cosmetic pesticide ban in Ontario protects our ecosystem but more importantly our lawn
care workers and residents from being exposed to true chemical pesticides, leaving only “bio-controls”, which include: iron, copper, vinegar, microorganisms, plant-oil-based pesticides and more. Ontario residents are protected from the dangers of chemicals on lawns but while the pesticide debate distracts consumers, the real threat to the future of humanity is the looming climate crisis, and your lawn can be an unforeseen contributor.
The real impact to our planet from lawn care comes from petroleum-based fertilizers (urea, ammonia, ammonium, nitrate and sulphate) and some of the mined fertilizer products (mainly potassium and phosphorus). Urea and potassium sulphate are probably the two most common nutrients found in fertilizer products in the lawn care industry and are derived from natural gas and potash mines. Canada is the largest global producer of potash4 and the 6th largest producer of natural gas5.
Natural gas is used to create ammonia and can then be synthesized into common fertilizer products. Ammonia production is estimated to generate 1-2% global CO2 (hundreds of million tons) production and subsequent nitrogen losses in the soil generate GHGs (N2O) 300x more potent than CO26. And then there is methane leakage as a result of the natural gas industry, methane is 80x more powerful in our atmosphere than CO2, and leakage estimates are not well known.
In conclusion, lawns can be maintained sustainably with a few changes to your traditional lawn care routine. Here are 5 ways your lawn can me more sustainable:
1. Trade your gas-powered mower for an electric one. Gas mowers produce the emissions of 8 passenger vehicles7.
2. Use organic fertilizers such as municipal biosolids, that are otherwise destined for our landfills. Fertilized lawns sequester more carbon into the soil than unmanaged lawns9
3. Keep grass clippings and tree leaves on site, either returning them to your lawn, the garden or compost pile.
4. Follow local watering restrictions.
5. Incorporate drought-resistant grasses such as turf-type tall fescue.
Bonus tip: Diversify your lawn with white clover, yarrow and wood sorrel to maintain a semi-uniform look with added drought & shade resistance.
References
6. https://climate.mit.edu/explainers/fertilizer-and-climate-change
7. https://psci.princeton.edu/tips/2020/5/11/law-maintenance-and-climate-change
8. https://pubs.acs.org/doi/10.1021/acs.est.0c00437
9.https://acsess.onlinelibrary.wiley.com/doi/abs/10.2136/sssaj2018.09.0359