TankBud

Giant baby tears

Micranthemum umbrosum

Also known as Pearl weed, Shade mudflower, Giant pearl grass, Giant pearlweed

FreshwaterStemCuttingsSide shoots

Giant baby tears (Micranthemum umbrosum)
Alex Popovkin, Bahia, Brazil · CC BY 2.0

Care at a glance

Light
Medium light
CO2
CO₂ beneficial
Temperature
68–82°F
20–28°C
Max height
7.9 in
20 cm
Growth rate
Fast
Placement
Midground
Type
Stem
pH
6.0–7.5
Hardness
2–15 dGH
Spread
3.9 in (10 cm)
Nutrient uptake
Water column
Growth region
Submersed or emersed
Difficulty
Easy
Family
Linderniaceae
Origin
Southeastern USA and Central/South America

Overview

A fast, easy stem plant best used in the midground or as a bushy mat, though it can be kept low like a foreground filler with hard trimming. It is mainly a water-column feeder with a weak root system, so dose liquid fertilizer rather than relying on root tabs. Bright light keeps it compact and bushy; moderate light gives looser upward growth. CO2 is optional but encourages dense growth and pearling. Under strong light it grows so quickly it needs weekly trimming, and the trimmed tops replant easily.

In the wild

Native to the southeastern United States from Texas to Florida and Virginia, and into parts of Central and South America, growing in ponds, ditches, and slow rivulets. In many areas it is emersed in summer and submersed in winter, so it handles both forms readily. It favors shadier, soft to moderately hard water habitats.

Good to know

Placed in the family Linderniaceae, this is the larger round-leaved pearl weed, distinct from the finer Micranthemum 'Monte Carlo' and the much-confused Micranthemum micranthemoides (formerly Hemianthus micranthemoides). The common name shade mudflower reflects its tolerance of low light. Underwater it carries small bright green ovate leaves in opposite pairs along soft creeping stems.

Did you know

Did you know this plant is named for the strings of tiny oxygen bubbles, or pearls, that cling to its leaves on a bright CO2-rich day, which is where the hobby name pearl weed comes from.

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