Ammonia has a high concentration of nitrogen, which can affect nutrient levels when applied to the soil. ... However, household ammonia is a caustic agent formulated for deep cleaning. This means it's highly corrosive, and when applied neat to garden weeds, is more likely to kill grass and other plants than to fertilize.

Will ammonia harm your grass?

Yes- ammonia does kill weeds. The problem- however- is that ammonia is a non-selective weed-killer and will kill all plants it comes into contact with. Therefore- if you've got desirable plants in your garden or grass growing on your lawn- you might want to avoid using ammonia solutions.

Is ammonia good for my lawn?

Ammonia provides a readily available source of nitrogen, a necessary nutrient for grasses to develop a healthy green color and produce new growth. Not all types of ammonia are created equal. Using the wrong type or too much of the right type can burn and kill your grass.