On the whole, koi fish are relatively straightforwards to care for and highly sought-after among pond owners. Choosing the right plants for your koi pond however can be a little more tricky. Koi are very inquisitive fish and will dig and have a go at pretty much anything. Introducing the right pond plants in the right way is crucial to ensuring a healthy habitat for your koi fish.
Every koi pond should have a mix of the following:
- Plants for shelter & shade
- Plants for oxygenating and filtering
- Plants to support the ecology of the pond
When doing research into the right plants for your koi fish, carefully consider the plants appropriate to your climate and varieties of fish. In this article we will be focusing on plants which grow well and support koi in the UK.
1. Water Smartweed (Persicaria amphibia)
Smartweed is a type of submerged plant which is generally not fussy and easy to grow. The plant can grow thick with the potential to rise up to 3 feet in height; because of this you may need to cut back the smartweed from time to time.
Below the water the plant is an excellent oxygenator and purifier. Smartweed provides a good habitat for small vertebrates and invertebrates, providing the food they need to thrive and in-turn a great source of food and protein for the koi.
2. Hornwort (Ceratophyllum demersum)
Hornwort is considered to be one of the top performing oxygenating plants. It is free-floating so has no roots so doesn’t require planting. It’s tolerant in a wide range of conditions.
For koi fish hornwort provides an excellent breeding area, but they do love to eat it so consider creating a boundary around it. Also keep in mind if you reduce their feed they may be inclined to to eat it.
Hornwort is sometimes referred to as coontail.
3. Horsetail (Equisetum Hyemale)
An extremely hardy marginal plant, horsetail has been around for millennia. It’s popular due to the fact that it provides a good source of shade for koi and they don’t tend to eat it. Horsetail does however attract micro-vertebrates which are a food source for koi. In addition this marginal plant is a great contributor to the oxygenating of the pond.
When you plant horsetail you can rest knowing that it doesn’t overtake or out-compete other plants.
Horsetail is sometimes referred to as scouring rush.
4. Water lily (Nymphaea)
A popular choice among koi pond owners, water lilies add both beauty and practicality to your koi pond. They can grow well in colder water with less sun in as little as 6 inches of water up to several feet.
Koi fish use water lilies for protection and also to lay their eggs on the underside of the pads. Consider however that koi like to eat the leaves and roots so consider netting or potting to protect them.
5. Water hyacinth (Eichhornia crassipes)
Water hyacinth is an easy to maintain free-floating plant which requires minimal care. This plant produces blue and purple flowers which attracts pollinators such as bees and hummingbirds.
Although koi do like to eat hyacinth it’s able to sustain itself thanks to it’s ability to reproduce and spread quickly; this does however mean that you may need to keep ontop of cutting back to prevent it from overtaking other plants.