Once you have the Leopard geckos that are sexually mature and in good health it's time to look into the possibility of mating them. The breeding season for Leos runs from February to September, although you can mate them out of season it is advised to follow their natural breeding season as much as possible. It is also worth mentioning very young or underweight female leos can sometimes be mated successfully but may not produce viable eggs, or will only produce the odd one or two eggs. If you are attempting to mate young/underweight leos I must also point out that this can cause stress and lead to the premature death to your breeders.