How to Care for Water Wisteria (Hygrophila difformis)

Water wisteria (Hygrophila difformis) is a very popular aquarium plant in the hobby because of its lacy leaves, bright green color, and rapid growth. It is relatively easy to care for but it can easily melt and lose its leaves once you buy it. Learn our top tips and tricks to plant your new wisteria and get past the melting phase. Then, propagate it to grow new plants.

What is Water Wisteria?

This aquatic stem plant is native in India and Thailand. It can reach heights of up to 20 inches (51cm) and widths of 10 inches (25cm). (Below 20 inches, light may have difficulty reaching the base of the Wisteria, and the bottom leaves might become thinner. Many people use this bushy species as a background plant in their fish tanks, but you can also plant it in the foreground or midground if you want to cut it shorter. As a fast-growing plant, it is often used to consume nitrogen waste compounds in the water and outcompete algae growth. However, if you do not provide enough lighting or liquid fertilizer, it will let you know by melting away from starvation.

Why does my new water wisteria not look like the pictures online?

Wisteria is a live aquatic plant that is commonly grown in commercial plants farms. The leaves and stems are taken out of the water, and the roots are kept in the water. This is an efficient way to grow plants faster, larger, and without pests and algae. Emersed-grown plants, or plants that have been grown above the water surface, generally have thicker stems and larger leaves that can absorb carbon dioxide from the air. Wisteria produces emersed foliage that looks like strawberry leaves. It has a oval shape of approximately 1.5 inches (4 cm) and grooved veins. The edges are slightly jagged.

Emersed-grown wisteria leaves

Once you place the wisteria in your fish tank, it must drop its old, emersed leaves and grow new, submersed leaves (or leaves that are grown completely underwater) that are capable of drawing carbon dioxide and other nutrients from the water. Submerged leaves look thinner, smaller, and more delicate than their emersed counterparts. Submerged leaves of Wisteria can look very different to their emersed counterparts. This can cause confusion. However, they are the same species that adapts to changing environments and changes their leaf appearance. Wisteria can grow underwater to produce bright green, feathery, and tall fronds measuring 4 inches (10 cm). Its bushy appearance can be used to add an interesting visual texture to planted tanks and is perfect for hiding fish fry or shrimp.

Submersed-grown wisteria leaves (on the right)

What are the differences between water wisteria, water, and water, sprite, and how do they look? Wisteria and water, both Ceratopteris.thalictroides, have delicate, lacy, similar leaves. However, when compared side by side, water, sprite has more needle-like, thinner leaves. Water wisteria, which is a stem plant, can form long branches along its stem. Water sprite, on the other hand is a fern species that produces new shoots from the central point of the plant.

Submersed-grown water sprite

How to Plant Water Wisteria

1. Carefully remove the stems from the rubber band, bundle, or rock wool inside the plastic pot. 2. Take care to trim any damaged stems and leaves during transport. 3. Use your fingers, or tweezers. Push the base of each stem into the gravel or substrate as deeply as you can. 4. Each stem should be planted separately, approximately 2 to 3 inches (22.5-5 cm) apart, so that they can develop roots and become anchored.

If you have fish that like to dig in the substrate, protect the newly planted stems by surrounding the patch of wisteria with a ring of rocks, wood, or other decorations. You can also grow wisteria as a floating plant. It simply rises to surface water and forms lots of hanging roots along its horizontal stem.

Planting water-wisteria in gravel using tweezers

Why is my new Wisteria plant dying?

Expect the wisteria to look beautiful for the first few days once it has been planted. Halfway through the first week, the emersed foliage will turn yellow and then brown. This is especially true near the base of the stems. Once the leaves are brown, you can remove the leaves if you wish to avoid having excess rotting organics in your aquarium. If the wisteria has a low level of light and/or nutrients, it may turn brown and melt. Replant the green, healthy parts of the wisteria by removing the soggy stems. As needed, add additional lighting and fertilizer.

Emersed-grown stem leaves at the base tend to brown first.

How to Convert Your Wisteria from Emersed to Submersed Growth

The conversion phase can take anywhere from a couple of weeks to a couple of months, depending on the fish tank’s light, nutrient, and carbon dioxide (CO2) levels. For a low tech tank with dimmer lighting and no CO2 injection, it may take about a month for the first submersed leaves to appear. You can speed up the process by using medium to high lighting in your aquarium. The wisteria should be placed directly under the sunlight. Also, provide lots of nutrients in the water column using an all-in-one liquid fertilizer, and add a mineral supplement if you have soft water with low amounts of GH. Although CO2 injection is not necessary, it will significantly reduce the conversion time as it provides more building blocks that the wisteria can use.

Plant the wisteria in a substrate and don’t move it. It will stop growing for a time if you move it around. Then, it will adjust to the new place and grow again. Make sure that your stems don’t grow out of water too much. They may develop more emersed than submerged leaves. If your wisteria is not converting, you can try floating some stems so they can receive more light and CO2 at water’s surface. You can then plant them again in the substrate once they have established enough roots. Keep the water parameters, lighting, fertilizer, and water quality stable as wisteria can easily melt in volatile environments.

At Aquarium Co-Op, we strive to source submersed-grown wisteria to jump start the conversion process and save you the hassle.

How to Propagate water wisteria

Once the plant is established, it will start to grow at a rate that is 0.5-3 in (1-8 cm) per daily. Cut off the top of the stems to prevent it blocking light and outcompeting other plants. Replant the trimmings to grow wisteria. The stem’s bottom half can be left in place and it will eventually sprout new leaves. However, if the bottom half is too “leggy” and lost most of its leaves during conversion or from lack of light, many people choose to remove it and plant the top half of the stem in its place. If the wisteria has begun floating, it should not cover more that 50% of the water surface. This will cause it to shade other plants, and lead to stagnant, oxygen-deprived waters.

The emersed leaves lower on the stems have developed holes and algae growth, whereas the new, submersed leaves at the tips of the stems are healthy and bright green. You can remove the submerged leaves that have reached several inches and replant them.