Of course not! You can do whatever you want with your lawn. You are in control of your lawn's destiny. You can tear up your lawn and plant an asparagus farm! NO ONE IS STOPPING YOU. Except maybe your spouse.
But if you want a nice lawn?
Then yeah, you probably have to feed it.
A healthy lawn basically comes down to three things: Water, cutting, and soil biology. Water is a no brainer, kinda. Things need water to grow. And we've already talked a bunch about the right way to cut your lawn.
So that leaves soil biology.
Soil is full of all kinds of rich and wonderful living things and awesome nutrients. It's its own little ecosystem and it's pretty much the perfect environment for growing stuff.
There are two major problems though...
Over time grass uses up the natural nutrients in the soil
Our soil sucks
The soil in the Adirondack area is really hard to grow grass in. It's not just you, I promise.
It's really sandy and there is a lot of clay, which means it's prone to compaction and doesn't hold nutrients well at all. Is your soil hard as a rock and it hurts your ears when you try futilely to jam a pencil in it? Thought so. Aerating can help with the compaction, but the microbiology will have to be replenished. That's where fertilizing comes in.
The three big names in soil nutrients are Nitrogen, Phosphorus, and Potassium (You down with NPP? Yeah you know me). That's what those three numbers you see on fertilizer bags means. So if it says 24-8-16 on the bag, it means it contains 24% Nitrogen, 8% Phosphorus, 16% Potassium, and 52% some other stuff, I don't really know what. Maybe it's banana peels.
Anyway, that's all awesomely good stuff to put in your lawn. Lawns up here seem to do really well with a higher nitrogen fertilizer. The exact ratios can change though, depending on the condition of your grass (Is it an established lawn? Baby grass? Weeds?) and the season. For example, in the fall the lawn will benefit from an extra boost of potassium which promotes root growth to help your grass winter over.
And you don't have to buy the stuff in the bags if you don't want to or if it just isn't in your budget (been there). A good compost gently raked into your lawn can help, and so can mulching your leaves and grass clippings into your lawn. But if I'm being really honest with you, because I like you, and I didn't say anything when you were dating that jerk even though I should have... you probably need to get some real fertilizer. How can you tell?
If you have put down grass seed for multiple years in a row, and it just won't stick... You should feed your lawn.
If you keep fighting weeds off with gallons of herbicides (DEC would like a word)... You should feed your lawn.
If your grass grows. so. slowly. Like you only have to mow every 3 weeks... You should feed your lawn.
If your grass is yellow and discolored and it's not from your dog peeing in the lawn damn it Rosco not again... You should feed your lawn.
So yeah, you should probably feed your lawn. Or plant asparagus.