I would like to note that nettle is indeed that tenacious weed! But still you can overcome it. Although some efforts will still have to be made. The most effective way to get rid of this plant is to weed along with the roots. Of course, the first time you can’t get all the roots, and therefore, after weeding, it is recommended to mulch the area with grass, straw, cardboard, newspapers. In general, any objects that will not allow light to penetrate. Namely, this phenomenon is the death of most weeds. After a year, dig again the area where the nettle grew, and remove the remains of the roots. That's all.
You can also try to spray nettle with a solution of potassium salt. But this method is not so true. You can water the area with nettle with hot water and salt - this is a long-known folk method.
Also for nettles, the creation of a lawn, which requires regular mowing, will be a fatal option.
Of course, you can also use various chemicals, such as tornadoes or roundups. But this treatment needs to be repeated: about three to four times.
However, do not forget that nettle is a kind of very useful weed. From it you can even cook soup and prepare a salad. In fact, there are a lot of vitamins and useful substances in this plant. It helps to get rid of various diseases.