Weed killers are chemicals that are used to get rid of undesired plants. However if weed killers are not chosen with care, they are as likely to harm many desired plants along with the weeds. Selecting weed killers with care is safer in the long run not only for the desired plants in the garden but also for the environment. There are not many weed killers that are safe for all desired plants. The best remedy is to use homemade weed killers with natural ingredients, as these are likely to cause minimal damage to other plants and are safe for the environment.
Because vinegar is highly effective at killing weeds and does not harm other plants, it is one of the most used weeds killers in organic gardening. To prepare weed killer, add half a teaspoon of dish-washing detergent to a gallon of vinegar. This helps to increase the penetrability of the vinegar into the soil and to the roots. Use a large squeeze bottle to apply the weed killer. Trim off any large leaves on the weeds so they don't get in the way, and apply the vinegar solution to the root area. Vinegar weed killer should be avoided in mixed beds, as it can harm some desired plants as well. Weeds treated with vinegar are usually dead within a couple of days.
Salt, or sodium chloride, is a commonly available, natural ingredient that can kill weeds without the use of store-bought chemicals. Salt has desiccant properties and, when applied in excess to any plant, it draws out the moisture from the plant and causes it to die. Salt is one of the oldest known herbicides; the mention of salt to destroy plant life is found in documents dating to the Roman Empire. Apply the salt to soil in a high concentration, without mixing it with water. A single of cup of salt works efficiently on 10 square feet of weeds. However, more can be used if this is not effective.
Liquid dish detergents are highly effective in getting rid of weeds, as they break down the waxy surface on the weeds. This makes the weeds susceptible to the effects of the acetic acid in the detergent, which gradually kills the weeds. The use of soap disintegrates the surface tension of the water, and this allows the chemicals in the detergent to stick to the weeds rather than running off, hence increasing the efficacy of the killing agents. Use one cup of soap for 10 gallons of water to make soap weed killer.