How to Care For Water Wisteria (Hygrophila Difformis).


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. While its care requirements are easy, this species is very prone to melting and losing its leaves when you first purchase it (similar to melting Cryptocoryne plants). Get our top tips for planting your new Wisteria, how to get past the melting phase and how to propagate it so you can grow new plants.

What is Water Wisteria?

This aquatic stem plant is native to countries ranging between India and Thailand and can easily grow up to 20 inches tall (51 cm) and 10 inches across (25 cm). (At greater heights, light has difficulty reaching the base of the wisteria and thus the bottom leaves may begin to thin out.) 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. This fast-growing plant is known to be a good eater of nitrogen waste compounds and can outcompete algal growth. If you don’t provide enough light or liquid fertilizer, the plant will tell you by melting away from starvation.

Why doesn’t my new water wisteria look like the photos online?

Wisteria, like many aquatic plants, is grown in commercial plant farms. It grows its leaves and stems from water and its roots in 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 leaves that look like strawberry leaves – featuring a roughly 1.5-inch (4 cm) oval shape, grooved veins, and slightly jagged edges.

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 produces bright green, feathery leaves that can reach up to 4 inches (10cm) in length. 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 can grow long stems, while water sprite creates new shoots at its base.

Submersed-grown water sprite

How to Plant Water Wisteria

1. Remove the stems of the rubber band and bundle the rock wool. 2. Trim any stems or leaves that were damaged during transportation. 3. Use your fingers or tweezers to push the stem’s base into the substrate or gravel as deep as you can. 4. To ensure roots develop and anchor the stems, plant them separately at a spacing of 1-2 inches (22.5-5cm).

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 the gravel with tweezers

Why is my New Wisteria Plant Dying

After you plant the wisteria, expect it to look good for the first couple of days. Halfway through the first week, the emersed foliage will turn yellow and then brown. This is especially true near the base of the stems. If the leaves turn brown, you can take them out to prevent your aquarium from absorbing rotting organics. The stems of wisteria that isn’t getting enough light or nutrients may become brown and eventually melt. Remove the soggy, brown stems and replant 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 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. It may take up to a month for submerged leaves to appear in a low-tech tank that has dimming lighting and no CO2 injection. To speed up this process, use medium to high lighting for the aquarium. Place the wisteria directly under the light and make sure other plants don’t cover it with shade. 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. CO2 injection is not required but will greatly shorten the conversion time since it provides more building blocks for the wisteria to use.

Plant the wisteria in a substrate and don’t move it. Every time you disturb the ground, it stops growing for a period of time while readjusting to the new location. 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. Once they start growing a decent amount of roots, then you can try planting them in the substrate again. 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, we strive to source submersed-grown wisteria to jump start the conversion process and save you the hassle.

How to Propagate Water Wiseria

Once the plant becomes well-established, it can start growing like a weed at a rate of 0.5-3 inches (1-8 cm) per day. You can remove the top half of the stems so that it doesn’t block the light or outcompete other plants. The bottom half of the stem can be left in the ground and will eventually produce new leaves. 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 is floating, don’t let it cover more than 50% of the water surface, or else it may shade out other plants and cause stagnant, oxygen-deprived water.

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