Think you’re smart and thrifty feeding flat beer to your lawn? Think again. Home remedies for lawn care may cost you more than you think.

We might love the idea of maintaining our lawns with non-toxic pantry products — soda, vinegar, and dish detergent — that help keep pesticides and other chemicals out of the environment while saving us a little money.

But do these home remedies really work as organic alternatives to traditional pesticides? And if so, do they really save money?

Not so much, say turf professors and pros.

“I wouldn’t waste my time,” says John Boyd, a University of Arkansas professor of weed science. “You can kill a weed with vinegar — in the better neighborhoods they use balsamic. But it’s not all that effective or cost-efficient.”

Also, home remedies — especially bug-killing concoctions — don’t have the same precision and accountability of store-bought lawn care products.

“They’re not labeled as pesticides, and have not been through any review or screening process,” says Dan Gilrein, an entomologist with the Cornell Cooperative Extension of Suffolk County in New York. “Materials may not be as benign as assumed — particularly when not used as intended.”

So are organic home remedies for lawn care a waste of time and money? Some are; some aren’t. Below, we break it down for you.

Boiling Water

Reputation: Weed killer

Reality: Undoubtedly, dumping boiling water on a weed will scald and kill some shallow-rooted, annual weeds, like chickweed. But it won’t wipe out the deep roots of perennial weeds, like dandelions, unless you repeat for days.

What’s more, the boiling water treatment is non-selective; not only can you scald yourself, but you can also kill grass and prized plants around the weed, says Craig Jenkins-Sutton of Topiarious Urban Gardens in Chicago.

Cost: How much is your time worth? By the time you boil the water, run it out to the garden before it cools, and carefully dump it on unwanted weeds, you could have grabbed a good weeder and dug up a garden full of dandelions — and those won’t come back.

Vinegar

Reputation: Weed killer

Reality: Acetic acid is a good general herbicide that sucks water from common weeds. But most pantry vinegar has only a 5% acetic acid concentration — too weak to kill all but the most tender, annual weeds. Perennial weeds — fuggedaboutit!

If you want to kill weeds with vinegar, you’ll need a commercial solution that’s 20% acetic acid. It’ll suck weeds dry, but will also dry out your prized plants, so be careful when spraying.

Cost: Distilled white vinegar: $2.40/gal.; commercial vinegar: $33/gal. (Note: Diluting it 1:1 with water will give you twice the amount of vinegar at a high concentration.)

Dish Detergent

Reputation: Insecticide

Reality: The Iowa State University Extension says it’s OK to use dish detergent, like Ivory or Palmolive, to kill soft-body insects, such as aphids, scales, and whiteflies. The soap destroys the waxy shell that protects the bugs, causing them to desiccate (dry up).

In a spray bottle, combine 1 tablespoon of dish detergent with 1 quart of water. Then thoroughly saturate the infected plants to completely wet the insects you want to kill.

One problem with dish soap, however, is that it can kill plants along with the insects. That’s where commercial insecticidal soaps have the advantage. Their formulas usually have a stabilizing agent that helps prevent the soap from damaging plants. Of course, you pay more for that formula.

Cost: Palmolive dish washing liquid: $3.30/10 oz.; Safer Brand Insect Killing Soap spray: $6.40/24 oz.

Soda and Beer

Reputation: Fertilizer that greens-up lawns

Reality: Home remedy guides say beer and soda contain carbohydrates and phosphorous, which feed lawns. Turf scientists, however, say that grass makes its own carbs from photosynthesis, and that soil generally has all the phosphorous a healthy lawn needs. Actually, phosphorous runoff is a watershed pollutant, and some municipalities are banning commercial fertilizers that contain phosphorous.

Spraying flat cola or beer on your lawn essentially just waters the grass, which can help it turn green.

Cost: Six 16-oz. cans of Bud: $7.80 (enough for a 10-by-20-ft. lawn)

So What’s a Greenish Lawn-Owner to Do?

First, know this: Lawns suck up more water than any other irrigated crop in the U.S. — so their very existence, arguably, is eco-unfriendly. If you’re dedicated to protecting life on Earth, replace your lawn with indigenous, drought-resistant plants or artificial turf.

Still, you might think life on Earth isn’t worth living unless you can wiggle your toes through cool fescue that’s not covered with toxic chemicals. If so, here’s some advice:

  • You’ll have to devote yourself to precisely mowing (with a push mower, if you want to be green), watering (deeply and less often), and fertilizing (with nutrient-rich compost). Diligent lawn care will keep out weeds naturally and promote beneficial insects that will eat the ones you don’t want.
  • Forget the idea of lawn perfection. Without chemicals, a few weeds will grow and some patches will turn yellow.
  • Spend a few extra bucks and buy organic lawn products that take the guesswork out of applying non-toxic solutions.

Related: Was Your Lawn Damaged by Severe Winter Weather? Here’s How to Fix It.