Pond Media Types and How to Pot Aquatic Plants
Hi, I’m Chris from Aqua Gardening.
If you’ve noticed a lack of blooming flowers, or growth is very slow for your pond plants, it is time to fertilise them! At the same time, it is often a good idea to re-pot them into a larger capacity pot or split them apart to allow them to grow.
Using a specialised fertiliser is the easiest and safest method, such as Clearpond Aquagrow Pond Tablets.
This plant food is specially formulated for slow release over 12 months.
You will need a few items to re pot your plants. Consider a fabric pot for larger plants and those which will need to sit a little deeper – or a net pot for those nearer to the surface.
Fabric pots will let water flow through without releasing any of the growing media. The pots are deep, with a height of 22cm for a 12L pot, which is 25cm in diameter. They also have the benefit of handles which makes them easy to pick up 12 months later when they become slippery underwater, so they suit the larger pond plants. Plastic net pots are also available, and we’ve found round pots with diameters of 200 and 300mm are the best. They will need a lining of geofabric to stop the media escaping, but because of their shallow depth, they can be planted in depths of just 15cm.
To plant the fertiliser tablets, you should follow our directions for potting. First we take the pot and if you’re using a plastic net pot, place a layer of permeable geofabric over the base. The geofabric should be very thin, such as the very affordable one we sell by the metre. On top of the fabric, place rinsed gravel of 8 to 13mm size up to a height of 2 to 3 cm from the base. Blue steel is a common type to use. On top of the gravel, add a layer of rinsed 2mm sized river sand with the fertiliser tablet planted inside. Plant the plant inside this layer. On the last 2 to 3 cm of height in the pot we recommend placing dark rounded pond pebbles, of about 30mm in length each.
These heavier pebbles prevent fish digging at the plants roots, and help blend the pot into the base of the pond.
Make sure the fertiliser tablet is buried completely; otherwise the fertiliser will leech into the water, and encourage algae to grow. In particular, an excessive of this nutrient shows up as microscopic free floating algae in the water making it look like pea soup.
If you find your pond is a little too deep for the plants, use besa blocks or a steel frame under the pond plants to get them to the right height. False bottoms are common in ponds for this reason, along with boosting the water volume which has other advantages.
At Aqua Gardening, we are experts in ponds! Watch on to see more frequently asked questions we receive about ponds, or follow the links below to see how you can get access to our exclusive members only online video training and knowledge database – not offered by anyone else in Australia!
I’m Chris from Aqua Gardening, and thanks for watching.
--- Update ---
2021 saw the release of Mineral Magic, an exciting silica based growing media. We have found the largest granule size: 4 - 10 mm (Aquaponics/Hydroponics) is great to use for potting pond plants. You can find out more about this product here.