Using Sugar as a Lawn Fertilizer: Myth or Microbial Magic?

When a reader asked about Charlotte Brunkhorst's suggestion to use sugar on lawns, the Long Island Gardener dug into the science—and the folklore—behind this sweet remedy. Charlotte, a Texas gardener, championed sugar as a chemical-free way to boost turf health. But does it actually work?

Mainstream science says no. The sucrose molecule is too large to enter plant roots, and student experiments show sugar-fed plants often end up stunted. Yet some gardeners swear by it. The likely explanation? Sugar feeds beneficial soil fungi—mycorrhizae—that form symbiotic networks with plant roots. Those fungi love the hexose sugars released when sucrose breaks down, and in return they help plants access water and nutrients.

The catch: this only works in a living, chemical-free soil. Herbicides, synthetic fertilizers, and fungicides kill the very microbes sugar aims to support. So if you want to try Charlotte's method, spread 4–5 pounds of plain white sugar per 1,000 square feet, water it in well, and—crucially—stop using lawn chemicals. The sugar itself won't burn grass or attract pests if it's watered in; a healthy soil food web will keep ants and grubs in check naturally.

Bottom line: sugar isn't a fertilizer in the traditional sense, but it can be a catalyst for microbial activity. Try it on a small patch, observe, and see if your lawn gets sweeter.