Fire ants can be real pests here in Florida. In the best case, you may step on a mound and get bit by a few ants. This will sting for a bit. But many people are allergic to red ant bites and need to be extra careful.
Beware of misinformation found on the internet. There are many sites claiming you can use popsicles with nutrisweet in them or boiling hot water with soap. You may kill a few ants this way but you will not take care of the bigger problem.
If you have a red ant infestation in your yard and you want to get rid of them naturally, there are a few options.
The first thing you want to do is get the ants feeding on something that will kill them. A very effective, natural product is boric acid. The worker ants will take the boric acid back to the mound. There, the larvae will eat it.
The larvae actually act as the food factory for the mound. When they eat the boric acid they will produce a by-product that the queen and worker ants will eat. In this way you are killing both the current and future generations of ants in the mound.
Another choice is to attack them with multiple products. Using a combination of boric acid and a botanically based dust from EcoSmart is very effective. Use the dust around the mound and where you think the ants will be walking. The ants will walk through the dust and then groom themselves. This will cause them to die.
Red ants are nocturnal so you will only see them in the day time if a mound is disturbed. Because of this, the best time to treat for red ants is in the evening, just before sunset. Give a thorough dusting around the mound and lay out your baits or boric acid. The ants will be affected when they emerge after dark.