A quick drive through almost any neighborhood with cool season lawn grasses quickly reveals the biggest lawn care mistake known to man - you are mowing too short! As I drive home from work or to the store or a function, I am constantly checking out peoples' lawns. That's right, I am critiquing and taking mental notes on every lawn I see. I admire the well kept lawns and wonder if the owner is responsible or perhaps a really good lawn service. I wonder too who is responsible when I see a lawn mowed too short and scalped to the point of turf damage. Unfortunately, it is the stressed, scalped lawns that I see a lot more of.
How does it get this bad?
How goes it get to the point that the majority of the lawns in any given neighborhood are being mowed incorrectly? I believe it to be a culmination of several factors both in the lawn care industry and among home owners. Mowing the lawn has always been seen as a necessary evil, often seen as punishment towards a teenager or at the very least a symbol of hard work when there is something better one could be doing. This attitude leads to the logic that mowing the grass extra short will somehow avoid or delay the inevitable task of mowing the lawn again. At the most, you can go an extra few days without mowing but the cost to the grass is significant and not worth the avoidance of sticking to a lawn care routine.
Another factor that I believe leads to mowing the lawn too short is television. People see highly manicured turf on TV and justifiably want it on their lawn. It's only grass after all, mow it short, keep it green and stripe it like Fenway Park right? Well not really. Highly manicured turf is mowed with specialized reel mowers and protected from stress with an dizzying array of chemical fungicides, herbicides, fertilizers and other products rarely seen by homeowners. Not to mention a computerized irrigation system and a caretaker and staff with more college degrees than one would believe. To be frank, many homeowners have unrealistic expectations when it comes to how their lawns should look.
Why is it so bad to mow the lawn short?
I understand why the short look is desirable. It is very aesthetically pleasing to see a dense turf mowed to around two inches or less, it truly looks like a golf course or other fine turf. The trouble is in the stress these heights put on the turf. A shorter lawn means less leaf blade on the plant, the less leaf blade, the less photosynthesis that can occur which means less shoot and root growth
When the lawn is mowed so low that the turf is scalped and the crown of the plant is injured, it opens itself up for a host of problems. As the plant puts all it's energy into recovering from the crown damage, it opens up a weakness in the lawn increasing the pressure from weeds, insects, and diseases. It is not uncommon for these short lawns to be struggling against weed invasions and grub infestations for an entire season. These conditions favor the never ending cycle of relying on herbicides and other pesticides to deal with problems that occur season after season. The multibillion dollar lawn care industry is only too happy to play along with the notion that insecticides and herbicides must be applied religiously every season.
So what's the solution?
Mow the lawn as high as possible. It's that simple. Set the wheels as high as you are willing to go, 3-3 1/2 inches is a great height. Mowing the lawn at this height, once a week (or less during heat and drought stress), will ease the stress to the plant and result in an overall healthier lawn. Using a mulching lawn mower is even better. Returning the clippings to the lawn saves work and provides another source of organic matter to the lawn.
A longer lawn means more leaf blade, this provides numerous benefits. More leaf blade means more photosynthesis which results in stronger, more prolific root and shoot growth, meaning the plant can greater withstand stresses like drought, insect infestation, and heat. It also creates a denser turf, able to crowd out weeds and providing a lawn that is arguable as attractive as a cropped, yet unhealthy, lawn. A lawn can be patchy, thin, and relatively uncared for, but when mowed high, looks just fine out the window or from the road.
The Weed-n-Feed connection
As the hate mail continues to fill my inbox regarding a blog I wrote regarding the Canada-wide ban on weed-n-feed, I can't help but think that a lot of the complainers are guilty of mowing their lawn too short (among other lawn crimes). Weeds are a messenger and their presence should not mean "get out the chemicals". Addressing the underlying problem is the key to controlling weeds and in many cases it is a simple as mowing the lawn a little higher. Try it.