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Pearl Grass
BeginnerMicranthemum umbrosum
A stem plant with small round leaves strung like pearls. Used in mid to background planting. Produces beautiful bubbles in water. CO2 injection encourages lush growth.
About
Pearl Grass (Micranthemum umbrosum) is a stem plant native to North and South America. Named for its small round leaves strung together like pearls. Beautiful oxygen pearling during photosynthesis makes it widely used in mid to background aquascaping. Grows denser and more vigorously with CO2 addition.
Size of the Pearl Grass
The Pearl Grass grows to 5-20cm.
Temperature & humidity for the Pearl Grass
The ideal temperature for the Pearl Grass is 20〜28℃.
Basic Info
Origin
North and South America
Size
5-20cm
Temperature
20〜28℃
Watering & Fertilizer
Liquid fertilizer + root tabs
Growing Tips
Lighting
Grows under medium or stronger light. With sufficient light it grows dense and vigorous, pearling on the leaves when photosynthesis is active.
CO2 & Fertilizer
CO2 injection makes it denser and more vigorous. Dose liquid fertilizer with potassium and trace elements regularly, together with substrate fertilizer.
Water Temperature & Quality
Prefers 20–28°C and slightly acidic to neutral water. Stable water conditions keep the tiny leaves dense and even.
Trimming & Propagation
Growth is moderate, and repeated trimming forms a beautiful bush. Replant the cut stems to propagate readily.
Pearl Grass FAQ
QWhat is the growing difficulty level for Pearl Grass?
Beginner. A variety suitable for beginners. No special equipment or experience is required—you can grow it without problems by setting up a basic cultivation environment.
QWhat is the ideal temperature for Pearl Grass?
The ideal temperature for Pearl Grass is 20〜28℃. Avoid sudden temperature changes and maintain a stable environment.
QHow large does Pearl Grass get?
The mature size of Pearl Grass is 5-20cm. This may vary slightly depending on cultivation environment and individual differences.
QHow should I water and fertilize Pearl Grass?
Pearl Grass: watering & fertilizer — Liquid fertilizer + root tabs. Aim for appropriate frequency and amount.
QWhat is the typical price for Pearl Grass?
The price of Pearl Grass varies significantly by variety, characteristics, size, and lineage. Please check GrowerDirect's price guide for the latest market information.
Last updated: September 25, 2026
References & Sources
Edited & verified by: GrowerDirect Editorial Team
The classifications, regulations, and growing data on this page are created and verified based on the primary information database below.
Taxonomy & Authority
Regulations & Conservation Status
Domestic law: The second edition of the Ministry of the Environment / MAFF Invasive Alien Species List for ecosystem damage prevention (published 11 September 2026) lists Micranthemum umbrosum (sold in Japan as "large pearl grass") as No. 184, a "control consideration" alien species (防除検討外来種). It is not a designated Invasive Alien Species, and growing or selling it is not legally restricted. Plants in cultivation are not subject to control, but do not discard them outdoors or let them escape with aquarium waste water or stem and leaf fragments (the list asks that listed species are never released into the wild).
Sources: Ministry of the Environment Designated Invasive Species List (Invasive Species Act) / CITES Appendix II listed plant taxa (family and genus level)
Regulations may change. Always verify the latest information with the relevant authorities.
Related Species
Find listings for this species
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