Instructions
Eliminate chemicals in your yard. Fireflies do not like the smell of many chemicals and will avoid any potentially harmful odors.
Reduce light in and around your lawn and garden. Extra lights will interfere with the fireflies light signals, so turn them off. Every time a firefly lights up, he is signaling to another firefly. Create an environment in which those signals are easy to see.
Leave an area of high grass or shrubbery. Male fireflies fly. Female fireflies will rest on tall pieces of grass or other shrubbery. If there is high grass and a lot of shrubbery, you'll see more fireflies.
Welcome slugs and snails. Fireflies love to feast on them.
Be patient. Fireflies start showing up at the beginning of spring, but will increase as the summer progresses. They tend to mate in late summer when the weather is warmest.