Today I’m talking with ecologist Katie Oxenham about frogs, how to make a frog pond and why we need frogs and ponds in our gardens. Frogs control lots of insects pests like mosquitos but also a range of other insects including cockroaches. People often worry that stagnant water in a pond will encourage too many mosquitos but if you keep the water occasionally circulating with a small pump, you shouldn’t have more mozzies than the frogs can handle.
You’ll need a pond for at least part of the frogs’ life cycle. You could dig a pond into the ground but even a pre-made above ground pond or water-filled pot on a deck or paving will attract them to your garden.
The best place to put the pond is out in a sunny spot, and not under trees that can drop leaves into it, particularly ones with toxic leaves like oleander or camphor laurel. Frogs can be noisy at night, so you might also want to keep it away from bedroom windows – especially your neighbours!
A larger pond is better but you have to watch its depth as deeper than 30cm (1ft) might mean you’ll need to fence it off. Create a deeper and shallow end so that the smaller frogs can get out easily but you can also put large rocks or a timber bridge in for those frogs that aren’t such good climbers, like most of the ground-dwelling frogs, such as the striped brown marsh frog.
A small pond will only attract the smaller frogs but in a larger pond, say over 1m (3ft) diameter, you may well end up with a wider range of frogs in your pond such tree frogs, as many frogs will quite happily cohabit with other species.
Include plants in your pond to give them shelter from predatory birds like kookaburras. They often like to sit up out of the water on water reeds to catch a little sun. But make sure that the plants don’t spread too far and cover too much surface area, especially plants like water lilies.
Frogs should find your pond without you having to do anything and DON’T ever take frog spawn from another place as you could be spreading harmful fungal diseases.