Learning Objectives
By the end of this lesson, learners will be able to:
- Identify the most common reasons plants decline in vivariums.
- Diagnose lighting, humidity, soil, or root-health issues.
- Adjust care to restore healthy growth.
- Choose species that thrive long-term in dart frog environments.
- Prevent plant die-off through proper planting techniques and maintenance.
Lesson Content
Plants are a core part of a bioactive vivarium — they stabilise humidity, offer cover, support microfauna, and make the enclosure beautiful.
However, many tropical plants struggle when first introduced, and new keepers often panic when leaves yellow, melt, or drop.
Plant decline is extremely common early on, and most cases are reversible once the underlying cause is identified.
This lesson covers the main causes, symptoms, and fixes.
1. Normal Plant “Melt” — What’s Actually Normal
Many plants will drop leaves, yellow, or look wilted for the first 2–6 weeks due to:
- root shock
- humidity changes
- lighting changes
- substrate differences
- transplant stress
This “melt stage” is normal for plants such as:
- Fittonia
- Peperomia
- Syngonium
- Begonia
- Selaginella
- most terrarium vines
As long as new growth eventually appears, the plant is recovering.
2. Not Enough Light
Insufficient lighting is the #1 cause of long-term decline.
Symptoms:
- leggy stems
- pale leaves
- slow or no new growth
- leaves pointing upward (“reaching”)
- moss turning brown
Fix:
- increase LED brightness to 70–90%
- reduce distance between light and canopy
- choose full-spectrum light with 6,500–7,000K
- run lights for 10–12 hours daily
Plants should visibly perk up within 2–3 weeks.
3. Too Much Light
Plant stress can also be caused by excessive light.
Symptoms:
- leaf bleaching
- crispy edges
- brown blotches
- rapid moss die-off
- algae explosion on leaves
Fix:
- reduce intensity by 10–30%
- raise the light 3–8 cm higher
- add floating leaf cover or bromeliads
- shorten photoperiod to 9–10 hours
Balance is key.
4. Incorrect Humidity
Tropical plants need stable humidity.
Too low:
- edges crisp
- leaf drop
- slow growth
- plants wilt between mists
Too high (constant saturation):
- fuzzy mould
- stem rot
- moss suffocates
- fungus gnats
- leaves yellow from overhydration
Fix:
- target 70–90% humidity
- ensure proper ventilation
- avoid misting soil directly
- mist leaves, not substrate
5. Poor Substrate Conditions
Plant roots are extremely sensitive in closed environments.
A) Soil too compact
Symptoms:
- slow growth
- drooping leaves (even if soil is wet)
Fix:
- add aeration (orchid bark, charcoal, pumice)
- reduce compaction at root level
B) Soil too wet
Symptoms:
- yellowing leaves
- root rot
- fungus gnats
- mushy stems
Fix:
- check drainage layer
- increase ventilation
- allow surface soil to dry slightly
- add more leaf litter
C) Soil too dry
Symptoms:
- crisp edges
- rapid decline
- slow recovery
Fix:
- increase misting frequency
- ensure moss retains humidity
- use deeper substrate layers
6. Nutrient Deficiency (Less Common in Bioactive)
Most terrarium plants get nutrients from:
- microfauna waste
- decaying leaves
- wood and bark breakdown
However, colours may fade if nutrients are too low.
Symptoms:
- pale leaves
- slow new growth
- poor branching
Fix:
- bury a small amount of worm castings
- top up leaf litter
- avoid liquid fertilisers — unsafe for frogs
A small nutrient boost goes a long way.
7. Plant-Specific Notes
Fittonia (Nerve plant)
- very sensitive
- often melts then regrows stronger
- prefers moderate light
Pothos / Epipremnum
- nearly indestructible
- great for beginners
- thrives in almost all lighting
Selaginella
- needs high humidity
- declines if airflow is too strong
- hates drying out
Begonia species
- sensitive to bright light
- enjoy dappled shade
- prone to melt but regrow fast
Philodendron / Syngonium
- strong climbers
- stable once rooted
- tolerate a wide range of light conditions
8. When a Plant Should Be Replaced
Replace a plant when:
- all stems are mushy
- roots have fully rotted
- new growth has not appeared in 6–8 weeks
- fungal infection spreads repeatedly
- the plant is entirely yellow or brown
Healthy replacements ensure the vivarium’s ecological balance.
Key Takeaways
- Most plants decline temporarily due to “melt” and recover naturally.
- Lighting problems cause the majority of long-term decline.
- Balanced humidity, airflow, and substrate conditions are essential.
- Never use chemical fertilisers inside dart frog vivariums.
- Replace plants only when recovery is clearly impossible.
