Using Terrestrial Plants in Aquariums

There are some plants offered in the aquarium industry that are doomed to fail in the average home aquarium. But just because some varieties of plants wont thrive in a submerged environment doesn’t mean there aren’t ways for you to enjoy them in your set-up in other ways. Sometimes you have to think outside of the “glass box” to bring a new dimension to your aquarium display.

Many aquarium displays of the past were boxed in by a hood or canopy, but especially with advances in lighting aquatic displays no longer have to be confined to the top of the aquarium. Some newer aqaurium designs even facilitate marginal plants and emerged growth.

How to Grow Emerged Plants in Your Display

Some plants that grow entirely submerged most of their days have the capacity to transform their new growth to a form that tolerates open air conditions. The emerged growth on these plants becomes more rigid so it can stand up without the support of the water and the stems and leaves become more waxy to retain vital moisture. Other plants may tolerate very moist or wet conditions, but must grow almost entirely out of the water and can only have submerged roots with the crown and/or foliage above the water. While these plants may tolerate being submerged for short periods, they typically lack the ability to adapt to the environment and the tissue will eventually rot.

In regards to the first kind, these plants can easily become established in an aquarium and nurtured so that they grow to the surface and then above. As long as they have adequate lighting and nutrients and providing that your aquarium has an open top, the plants will continue to grow, eventually showing their heartier leaves and stems. They may even produce blossoms, as you can see in the photo of the aquarium lily we had in a previous display. The emerged growth can be trimmed and maintained according to your taste.

Some of you may have had (or still have) a betta vase with a peace lily growing out of the mouth of the vase. Growing other terrestrial plants in water is just as easy, though depending on your set-up you may need to be creative. If your aquarium has an overflow box, a pond planter basket can make a perfect venue for growing a small, emerged garden. Find a basket that fits to the dimensions of your overflow and choose the moisture loving potted plant(s) you like. Rinse any soil thouroughly from the roots and plant your selection in the basket using pond planter media, clay balls, or fine gravel. You should be able to them suspend the basket or prop it in the opening of the overflow box. the water from the tank should trickle through and around the basket, keeping the roots of the plant moist, and the flow should not be impeded. If you don’t have an overflow box, you may try using a small floating planter (if you have space for the plants to grow) or an acrylic frag shelf to anchor cuttings to the edge of the tank. Place the raw ends of the cuttings into the holes in the shelves and drape the cuttings over the edge of the tank. All it takes is finding a creative solution to keeping a plant’s foliage above the water line. 

Our half circle display was manufactured perfectly for creating a submerged/emerged display. We used fully aquatic varieties of plants (Cryptocorynes, Subulata, Nymphaea), accented with a few marginal/emerged plants (Umbrella Palm, Peace Lily), then topped off with some donated houseplant cuttings (Callisia or Bolivian Jew) in the unique cascade. The cuttings quickly rooted in the water trickling down the faux rock backdrop and really tied the display together.

Troubleshooting

Adding the emerged element to your display is not only aesthetically pleasing, but the roots of the plants provide a place for fish to hide and can help to biologically filter the tank. There are some things to watch for though. As plants grow, be aware of how close they get to lighting fixtures so the leaves don’t burn. Emerged growth is also prone to outside pests such as aphids and spider mites. Observe the condition of the leaves in case pests become a problem. A small fan to circulate across the emerged foliage can help to ward off these pests. Finally, be sure that the cuttings you use do not secrete sap which may pose a problem for fish. I’ve personally never encountered a problem with toxicity with the cuttings I’ve used, but if larger herbivorous fish mangle the plants or are given accidental access to the foliage, be sure to remove the debris so it cannot decay in the aquarium. 

Suggestions

There are several common houseplants that can be easily rooted in water in my experience. Keeping in mind that the foliage should not be in the water and accessible to your fish, these may be good candidates for you to experiment with:  Philodendron (vining), Wandering Jew, Syngonium, and spider plants. Terrestrial plants that do well with “wet feet” include Dracaena, peace lilies, and many others.

Feel free to ask questions in the comments section,

Thanks,

Patty