Water wisteria

Quick facts

Max height

50 cm

Growth rate

fast

Difficulty

beginner

Placement

midground, background

Propagation

cuttings

Water parameters

Temperature

20–28°C

pH

6.5 to 7.5

Hardness

2 to 18 dGH

Light and nutrients

Lighting

medium

CO2

not required, but boosts growth and color

Substrate

any

Feeding

feeds from both water column and roots (liquid ferts plus root tabs)

Substrate

What this plant roots into (or attaches to). The substrate affects both plant nutrition and water chemistry; see each linked page for full effects.

This plant feeds primarily from the water column, so substrate choice matters more for its fish-tank compatibility than for plant nutrition.

With fish

Plant-eating fish

will be eaten by mollies, silver dollars, large goldfish, and other plant-grazers

Diggers (corydoras, loaches)

fine - root system or attachment style handles it

Root-disturbing fish

tolerates fish that disturb roots

Habitat

Native to the Indian subcontinent, found in marshes, shallow water, and wet margins across India, Bangladesh, and Nepal. The species (Hygrophila difformis) produces deeply lobed, fern-like submerged leaves that are completely different from its simple, oval emersed leaves. This dramatic heterophylly (different leaf shapes above and below water) is one of the most extreme in the aquarium plant world. Submerged leaves can be 8–15 cm long with deep, irregular lobes that create a lacy, fern-like appearance. The plant grows as a fast-growing stem that branches freely, forming dense, bushy masses. Water wisteria has been a popular aquarium plant since the 1960s for its unusual leaf shape, fast growth, and ease of care. The extreme difference between emersed and submerged leaf forms means newly purchased plants (typically farm-grown emersed) need 1-2 weeks to transition. The simple emersed leaves drop and are replaced by the deeply lobed submerged foliage. This transition can look alarming (apparent plant death) but is normal. In some countries, Hygrophila difformis is listed as a potentially invasive species; check local regulations before outdoor cultivation.

Outdoor pond use

This species transitions to outdoor ponds well, not just indoor aquariums.

Outdoor pond zones (USDA)

8 to 13 (winter low around -12°C or warmer)

Below the minimum zone, the plant won't overwinter outdoors but can still be grown seasonally and overwintered indoors. Several pond-friendly species (water hyacinth, water lettuce, parrot's feather) are regulated as noxious in some jurisdictions; check the legality data on the profile before releasing anything to an outdoor body of water.

Care notes

Easy. Grows in low to high light, without CO2, in any water chemistry (pH 6.0-8.0, soft to hard), temperature 20–28°C. Under moderate to high light, the submerged leaves develop the full, deeply lobed, fern-like shape that makes the plant attractive. Under low light, the lobes are less pronounced and the leaves are simpler. Plant stems in groups, pushed into substrate. Growth is fast: 5–15 cm per week under good conditions. Trim tops and replant weekly; the cut stems produce multiple side shoots, creating increasingly bushy growth. The rapid growth makes water wisteria excellent for nutrient export and algae competition in new or overstocked tanks. Nutrient requirements are moderate; liquid fertilizer prevents the older leaves from developing pinholes and yellowing. The deeply lobed leaves provide excellent shelter for fry and shrimp, functioning similarly to floating plants but as a rooted background or midground species. Propagation by cuttings is easy and reliable. Available from most pet stores at low cost. A classic beginner plant that combines unusual aesthetics with bulletproof hardiness.

Further reading

• How to cycle a fish tank
• Water chemistry for fishkeepers: pH, GH, KH, and what they mean