A dog and his friend.
Dog owners, beware. Many commercial-made weed killers use chemicals that can be harmful to your pet, so reading the instructions before applying it, and keeping dogs, kids and other pets away, is a good idea. However, there are many ways to kill weeds that will do the job well, without endangering man's best friend. Generally, these methods are simple, cost effective and work as well as any chemically-made weed killer on the market.
Although many weed-killing alternative solutions use fairly harmless, non-toxic solutions, it is a good idea to be prepared when using any substance for the purpose of killing weeds. Safety glasses or goggles are a must when dispensing or spraying any kind of solid or solution onto your lawn. Eye irritation or worse can be easily prevented by using a good pair of glasses or goggles.
Long sleeve shirts and trousers will keep any substance from touching your skin. Even natural weed killers may contain organic irritants. It's a good idea to wear gloves to protect your hands, as well.
One of the best ways to kill weeds naturally and keep them from coming back is using salt. A pinch of salt placed at the base of a weed will leach into the soil, upset the pH balance of the plant and effectively kill it. Salt dirt or gravel drives heavily, and weed growth will be contained for many months.
Sugar can be added to your salt mix, as well as some chopped up chilli peppers to prevent your favourite pet from eating what you've placed on the ground. It works the same way as regular salt, and you won't have to worry about your pet's health.
Sprinkling cornmeal into cracks and crevices will control weeds in hard-to-reach places. No need to pull them up anymore, just put some cornmeal into the cracks, and the weeds will soon be gone.
If there is one thing that will kill weeds immediately, it's dousing them with boiling water. This is an age old remedy for intrusive weeds, and about as natural as it gets. This may not be the best spot weed killer of the bunch, because if there is any run off to the sides as you pour, it will kill everything around it, but boiling water is a good solution for large areas. Consider drenching cracks or crevices with boiling water and then lay cornmeal into them as a double whammy. Be careful, as scalding water can seriously burn your skin.
Another timeless and natural weed killer is vinegar. The acids in vinegar, although mild to us, are killers for weeds. Target the base of the weed so the vinegar can get into the root system and kill the weed.
Mix 1 gallon of white vinegar, 1 cup of regular table salt and 1 tsp of dishwashing liquid, preferably something that is biodegradable. To make less, cut the quantities in half or quarters for what suits your weed problem best.
Spray the mixture on offending weeds to kill them without harming your dogs, kids or other pets. Once again, be careful where you spray, as this mixture is very strong and will kill any kind of plant it comes into contact with. The higher the acid content in the vinegar, the more potent it will be.