Micranthemum umbrosum


Background History

Micranthemum umbrosum is an adaptable aquatic plant suited for practically any type of layout or aquarium condition.  Indigenous to Central America and abundantly in North America, this plant can be found in shallow ditches, streams, and marshlands.

Although it appeared in earlier aquariums layouts, Micranthemum umbrosum was brought center stage in the late 1990s by in Japanese Aquascaper, Takashi Amano, who demonstrated its practical beauty and ease of trimming to create a stunning midground bush.

Micranthemum umbrosum is a commonly known as Baby Tears and Pearl grass.

Growth Characteristics

Micranthemum umbrosum is an undemanding plant that only requires bright light to survive and thrive. It is adaptable to less light conditions and minimum fertilizers; however its best growth is spurred through light and carbon dioxide injection.

Each stem reaches a height of 4-8 inches (10-20 cm) and a leaf width of about 1 inch (2 cm).  It produces whorls of two rounded leaves at each internodes.  This is the most distinguishable underwater characteristic that makes it differ from Hemianthus micranthemoides, which has 3-4 whorls per node.

Micranthemum umbrosum grows fast under high light conditions. It will produce side shoots that can be cut and replanted to propagate this plant. If allowed to reach above the water surface, it will produce tiny white leaves at the nodes.

Aquascaping Application

Micranthemum umbrosum is a stunning aquatic plant that can be trimmed to fit any layout.  Under high light, this plant can be trained to creep along the substrate by initially planting horizontally and trimming any vertical side shoot growth.

Round, manicured bushes can also be created through regular trimming and replanting of the cuttings.  These bushes are commonly used in Dutch Aquascapes, but have also found its way into Nature layouts. 

Plant Profile
Scientific Name: Micranthemum umbrosum
Common Name: Baby-Tears
Difficulty: Moderate
CO2 Requirements: Moderate
Lighting Requirements: Medium
Plant Arrangement: Midground
Growth Rate: Fast
Family: Scrophulariaceae
Genus: Micranthemum
Origin: North and South America
Plant Type: Stem
Water Hardness: Medium (GH = 9-13 dH)