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?

The aquatic stem plant can grow to a height of 20 inches (51 cm) or 10 inches (25 cm) in countries between India and Thailand. (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. It will however, let you know if there is not enough lighting or fertilizer by melting when it becomes starved.

Why is my new water not looking like the pictures?

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 grown above the water surface) generally have thicker stems that are built to withstand gravity and broader leaves that can absorb carbon dioxide directly 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. Wisteria produces submersed leaves that look drastically different from their emersed growth, which can lead to a lot of confusion, but they are in fact the same species that changes its leaf appearance to adapt to different environments. When grown underwater, wisteria has bright green, feathery fronds that can reach 4 inches (10 cm) across. Its bushy appearance can be used to add an interesting visual texture to planted tanks and is perfect for hiding fish fry or shrimp.

Submerged grown wisteria leaves (on left)

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 to push the stem’s base into the substrate or gravel as deep 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. Alternatively, wisteria can also be grown as a floating plant where it simply rises to the water surface and develops lots of hanging roots all along the horizontal stem.

Planting water-wisteria in gravel using tweezers

Why is My New Wisteria Plant Dying?

The wisteria will look great for the first few days after it is 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. You can remove the leaves once they have turned brown if you don’t want to have excess rotting organics. The stems of wisteria that isn’t getting enough light or nutrients may become brown and eventually melt. Cut off the brown, soggy stems and replant the healthy green parts of the wisteria. Then add more lighting or fertilizer as needed.

Emersed-grown leaves at the base of the stem tend to brown and melt off 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. A low-tech tank may require a month to see the first submerged leaves. You can speed up the process by using medium to high lighting in your aquarium. Place the wisteria directly in front of the sun and ensure that other plants do not shade it. Make sure to add lots of nutrients to the water column by using an all in one liquid fertilizer. You may also need to add a mineral supplement if your water has low levels 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. You can stop the ground from growing if it is disturbed. It will then adjust to the new environment and continue to grow for a while. You should also ensure that the stems do not grow too high or out of the water. Otherwise, they might develop more emersed foliage instead of 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. After they have grown enough roots to be able to plant in the substrate, you can replant them. You should also keep your water parameters, lighting, as well as fertilizer stable. Wisteria is prone to melting if its environment becomes volatile.

At Aquarium Co-Op our goal is to source submerged-grown Wisteria to speed up the conversion process and to save you the trouble.

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. You can remove the top half of the stems so that it doesn’t block the light or outcompete other plants. You can leave the bottom half of the stem in the ground, and it will eventually grow new leaves from the tip. If the bottom half of the stem is too “leggy”, or has lost most of its foliage due to conversion or lack of sunlight, some people decide to remove it and place the top half of their stem. 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. Once several inches of submerged leaves have grown, you can trim off the healthy tips and plant them again to replace the emersed-grown portions.