A pond creates a home for some of the 26 Sydney frog species, as well as for fishes, provides a water source for birds and beneficial insects like bees, and adds extra diversity for a healthy garden ecosystem. There are a range of edible plants you can grow in and around ponds, like water chestnuts, Vietnamese mint, hyssop, watercress, water parsley, taro, lemongrass, and water spinach.
You can also grow the amazing floating water fern, azolla. It helps keep out mosquitoes, and tadpoles love it. Azolla is high in protein and minerals and fixes nitrogen. It can be fed to your chickens and ducks and used as a compost activator, which is lucky as it grows very fast in summer – doubling in size every two days!
Building a pond is easy. You can buy precast fibreglass or plastic ponds to drop into a hole. For a more free-form design, dig a hole and line it with black UV-resistant pond liner. You can even create simple above-ground ponds in a large pot or bathtub. Sydney frogs will lay eggs pretty much anywhere they can access water (including buckets and wheelbarrows full of rainwater!).
Find a spot that gets both sun and shade, ideally shaded from the hot afternoon sun. You want some sun to allow algae to grow to feed tadpoles, but too much sun brings too much algae and lowers water quality. Fill the pond with fresh rainwater. If you use tap water, let it stand in the sun for about five days to allow the chlorine to dissipate.
You will need plenty of plants, rocks, and logs in and around the pond to provide shelter and shade. Add an overflow pipe or ditch in case of heavy rain, but make sure any non-native fish can’t escape to local waterways. Make sure you include a variety of depths and a way for frogs to get out – gentle slopes, rocks and logs will all help.
If you are worried about mosquitoes, Chinese white cloud mountain minnows are small, hardy fishes that eat mosquito wrigglers, but leave frog eggs alone.