Acmella repens

Acmella repens, the Oppositeleaf spotflower, is a little known, rare stem plant. It occurs as a swamp plant in the warmer parts of the Americas from the southern USA to Paraguay in several wet places and is able to grow submerged. Aquarists collected it in Texas years ago and discovered its suitability as aquarium plant. Since around 2012 it is also known in Europe. Acmella repens belongs to the sunflower family (Asteraceae) and is closely related with the Pará cress or Jambú (Acmella oleracea). It resembles Gymnocoronis spilanthoides except that it is considerably smaller. In its suberged form it grows strictly upright with quite long internodes and opposite, egg-shaped, medium green leaves. Strong lighting causes red-brown coloration of the stems, petioles and leaf midribs. When it is allowed to grow out of the water, one may expect its nice little yellow inflorescences that resemble tiny sunflowers.

Quick Care Guide:

• Family: Asteraceae
• Height: 2-4 inches
• pH: 6.0-7.5
• Care Level: Easy
• Light Requirement: Medium to High
• CO₂: Not essential, but beneficial for optimal growth
• Propagation: By runners
• Growth Rate: Moderate to Fast

Care Tips:

• Light Conditions: Acmella repens thrives in medium to high light. Under sufficient light, it produces vibrant green leaves and may even develop small yellow flowers. Low light may result in leggy growth.
• Substrate: This plant prefers a nutrient-rich substrate to support its spreading growth habit. It can also benefit from root tabs or liquid fertilizers for enhanced growth.
• Water Quality: Acmella repens prefers stable water parameters with regular water changes to maintain clean, healthy conditions. It is generally hardy and adaptable to a wide range of water conditions.
• Trimming: Regular trimming is necessary to maintain a compact, bushy shape. You can propagate it by cutting and replanting the runners, which will quickly root and spread.

Acmella repens is a great plant for aquascapers looking for a low-maintenance foreground or midground plant with good spread potential. Its bright green leaves and occasional yellow flowers bring a touch of vibrancy and interest to aquariums.