I have seen arguments on both sides around the idea of “No Mow May” and they both sound founded.
One idea is that the early flowers like dandelions are not offering much for nutrients to our pollinating community, which is the biggest reason mentioned for not mowing the lawn this month.

“No Mow May” is a good start to rethinking bee health across our lawns

 

Now even if that is true, any excuse to get people talking about bees is a good thing.
I remember as a kid it was always said that “bees will sting you, run away, I hope it flies off soon.”  Today’s conversation is more along the lines of “hello bee, thank you for coming by, need anything?  Make yourself at home and please don’t let me bee a bother” haha.

But then there is this concern around long grass:

You have to remember that when grass gets too long, it can prevent sunlight, water and nutrients from reaching the soil properly. Not only that, long, damp grass can quickly become a breeding ground for lawn fungus and other lawn diseases, etc. 

What Happens If Grass Gets Too Long?

So the way I see it, May is the month to mow if you get chance.  If you don’t get to it, you are observing “No Mow May” and if you do mow your lawn, you are concerned about the health of the grass and don’t want it to get too long.
So far it is a No Mow May for me haha.