> Any breeding tips would be welcome as I have not managed to breed any of my dartfrogs. I keep azureus and leucomelas.
The procedure for some of the thumbnail frogs can be a bit different, but for the larger dartfrogs species such as azureus and leucomelas it's usually much the same.
First of all, you need to have a male and a female. Don't laugh, on two separate occasions I've spent over a year trying to breed a group of males (it doesn't work!). Get some help if you're not sure. The frogs need to be adult or near adult (usually 8-12 months) before you can determine their sex with confidence.
These species breed best as pairs. You can get away with more than one male if your vivarium is big enough, but females will fight and even if one does not kill the other(s), usually not breed very successfully. The frogs need to be old enough, in good condition and not stressed to breed successfully.
Even in a heavily planted vivarium, the frogs prefer a spawning site. The classic is half a coconut shell with a notch in the rim, and a plastic lid of a leaf underneath for them to lay the eggs on. Most frogs will use this secluded spot in preference to anywhere else, and this makes it easy for you to check if there are any eggs. If you find eggs, leave them for at least a day before removing them to make sure they have been fertilized. Don't keep interfering with the frogs though - I usually check my vivaria for eggs once a week.
Once they are mature and the males are calling regularly, give them as much food as possible and spray heavily, e.g. 2-3 times a day. That should do the trick after a few weeks. If not, give them a one month break (less food, less spraying and a little cooler if possible), then repeat the conditioning process.