Landscape Architecture Research
A comprehensive analysis of 23 species for interior planting specification, including 19 native warm-temperate evergreen broadleaf species and 4 supplementary tropical/subtropical specimens. Light requirements, humidity thresholds, and indoor survival assessment for each forest stratum.
→ Tokyo Office Atrium — Case Study & Sunlight AnalysisQuick Answers
The answer depends on the forest stratum. Canopy trees need engineered atria. Understory and ground cover species are strong indoor candidates.
All 23 species rated Good or better for indoor contexts with appropriate lighting.
Aspidistra elatior recommended minimum 0.5 mol/m²/day (absolute survival floor: 0.2) — the lowest of any species. Design the atrium lighting to deliver 2–8 DLI across layers.
Ficus elastica and Hedera rhombea tolerate 30% RH. Most species need 40-50% minimum. Ferns need 45-60%. Design target: 60-70% RH at foliage level with gentle air circulation.
Ecosystem Structure
Species organized by their natural position in the Japanese evergreen broadleaf forest. Border colour indicates indoor viability rating.
Complete Dataset
Click column headers to sort. DLI = Daily Light Integral (mol/m²/day). klxh = kilolux-hours (klux × 15h photoperiod). RH = Relative Humidity.
Container-grown height ranges for all 23 species, grouped by forest layer
| Species | Layer | Indoor Ht. | Indoor Viability | Ext. DLI | Int. Min DLI | Int. Min klux | Min klxh | Ideal klux | Ideal klxh | Opt. RH | Min RH |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Bucida bucerasBlack Olive Tree | Canopy ‡ | 1–3 m | Moderate | 30–65 | 6–8 | 3.0–5.0 | 45–75 | 10–15 | 150–225 | 50–70% | 40% |
| Daphniphyllum macropodumFalse DaphneYuzuriha | Sub-canopy | 2–4 m | Best | 2–10 | 2–3 | 1.0–1.5 | 15–22.5 | 5–7 | 75–105 | 60–80% | 45–50% |
| Distylium racemosumIsu TreeIsunoki | Sub-canopy | 1.5–3 m | Best | 3–15 | 2–3 | 1.0–1.5 | 15–22.5 | 5–7 | 75–105 | 60–80% | 45–50% |
| Neolitsea sericeaJapanese Silver TreeShirodamo | Sub-canopy † | 2–4 m | Moderate | 4–20 | 3–4 | 1.5–2.0 | 22.5–30 | 5–8 | 75–120 | 60–80% | 45–50% |
| Ilex rotundaRound-leaf HollyKurogane-mochi | Sub-canopy † | 2–4 m | Moderate | 8–25 | 3–4 | 1.5–2.0 | 22.5–30 | 5–8 | 75–120 | 50–70% | 40–45% |
| Ilex integraMochi TreeMochinoki | Sub-canopy | 2–4 m | Moderate | 8–25 | 3–4 | 1.5–2.0 | 22.5–30 | 5–8 | 75–120 | 50–70% | 40–45% |
| Ficus elasticaRubber Plant\u30A4\u30F3\u30C9\u30B4\u30E0\u30CE\u30AD | Sub-canopy | 2–3 m | Very High | 20–50 | 2–3 | 1.0–1.5 | 15–22.5 | 4–8 | 60–120 | 40–60% | 30% |
| Ficus benjaminaWeeping Fig\u30D9\u30F3\u30B8\u30E3\u30DF\u30F3 | Sub-canopy | 2–5 m | High | 20–45 | 3 | 1.0–2.0 | 15–30 | 5–10 | 75–150 | 50–70% | 40% |
| Ficus microcarpaChinese Banyan\u30AC\u30B8\u30E5\u30DE\u30EB | Sub-canopy | 1–4 m | High | 25–55 | 3 | 1.0–2.0 | 15–30 | 5–10 | 75–150 | 50–70% | 40% |
| Fatsia japonicaJapanese AraliaYatsude | Understory | 1–2 m | Very High | 2–6 | 2–4 | 1.5–4.0 | 22.5–60 | 4–6 | 60–90 | 40–60% | 30% |
| Aucuba japonicaJapanese LaurelAoki | Understory | 0.6–1 m | High | 2–6 | 2–4 | 2.0–4.0 | 30–60 | 3–6 | 45–90 | 50–70% | 30% |
| Sarcandra glabraGlabrous SarcandraSenryo | Understory | 0.5–1 m | Mod-High | 1–4 | 2–4 | 1.5–3.0 | 22.5–45 | 3–5 | 45–75 | 60–80% | 45–50% |
| Ardisia sieboldiiSiebold ArdisiaMoku-tachibana | Understory | 1–2 m | Mod-High | 3–6 | 3–5 | 2.5–4.0 | 37.5–60 | 4–6 | 60–90 | 50–70% | 40% |
| Cyrtomium falcatumHolly FernOni-yabusotetsu | Ferns | 0.3–0.6 m | Excellent | 3–6 | 1–2 | 1.0–2.0 | 15–30 | 3–5 | 45–75 | 50–70% | 45–50% |
| Dryopteris erythrosoraAutumn FernBenishida | Ferns | 0.3–0.6 m | Good | 5–8 | 2–3 | 2.0–3.0 | 30–45 | 3–5 | 45–75 | 50–80% | 40–45% |
| Polystichum polyblepharumTassel FernInode | Ferns | 0.3–0.6 m | Moderate | 3–6 | 2 | 2.0 | 30 | 3–5 | 45–75 | 60–80% | 45–50% |
| Coniogramme japonicaJapanese Bamboo FernIwaganesou | Ferns | 0.6–0.9 m | Moderate | 3–6 | 2–3 | 2.0–3.0 | 30–45 | 3–5 | 45–75 | 60–90% | 50% |
| Aspidistra elatiorCast Iron PlantHaran | Ground cover | 0.3–0.6 m | Outstanding | 1–4 | 0.5–1.0 | 0.5–1.0 | 7.5–15 | 2–4 | 30–60 | 40–60% | 30% |
| Hedera rhombeaJapanese IvyKi-zuta | Ground cover | 0.1–0.3 m | Good-Exc | 3–6 | 0.5–1 | 0.5–1.0 | 7.5–15 | 3–5 | 45–75 | 40–60% | 30–35% |
| Carex morrowiiJapanese SedgeKansuge | Ground cover | 0.3–0.45 m | Good | 4–8 | 1.5–2 | 1.5–2.0 | 22.5–30 | 4–6 | 60–90 | 40–70% | 30–40% |
| Ophiopogon japonicusMondo GrassJanohige | Ground cover | 0.15–0.3 m | Good | 4–8 | 1.5–2.5 | 1.5–2.5 | 22.5–37.5 | 3–5 | 45–75 | 40–60% | 35–40% |
| Ardisia japonicaJapanese ArdisiaYabukouji | Ground cover | 0.15–0.3 m | Mod-High | 1–4 | 2–4 | 1.5–3.0 | 22.5–45 | 3–5 | 45–75 | 60–80% | 45–50% |
| Liriope muscariLily TurfYaburan | Ground cover | 0.3–0.45 m | Moderate | 4–20+ | 2–3 | 2.0–3.0 | 30–45 | 4–7 | 60–105 | 40–60% | 35% |
Design Specification
Environmental targets for interior planting design using this species palette.
0.5–2 DLI (7.5–30 klxh) • 30%+ RH • Standard HVAC
2–4 DLI (30–60 klxh) • 40%+ RH • Near glazing or supplemental LED
3–6 DLI (45–90 klxh) • 50–70% RH • Humidification required
4–12 DLI (60–180 klxh) • 60–80% RH • Engineered environment
Humidity: 60–70% RH at foliage level. Never below 45% sustained. Pair with gentle air circulation (0.3–0.5 m/s) to prevent fungal disease.
Temperature: 10–25°C core range. Seasonal swing beneficial (cooler winters, warmer summers). Brief 30°C excursions tolerable with high humidity.
Lighting: No zone below 2 DLI (except Aspidistra/Hedera zones). Canopy layer: 8–12 DLI at crown. Sub-canopy: 4–8 DLI. Supplemental LED grow lighting is mandatory for all tree species.
Substrate: Deep, humus-rich, moisture-retentive but well-drained structural planters. pH 5.5–7.0 (acidic to neutral).
Data Integrity
Shade tolerance ratings: HIGH confidence — consistent across PFAF, ecology literature, and multiple horticultural databases.
DLI minimums: MEDIUM confidence — inferred from ecology (understory light transmittance) and general shade-plant DLI research. No published species-specific indoor DLI trials exist for most species.
Ideal klux: MEDIUM confidence — cross-validated across PFAF shade classifications, NCSU/RHS horticultural profiles, IFAS interior foliage guidance, and ecology-based inference. Values represent the range where each species is expected to produce compact, well-coloured growth in a controlled indoor environment.
Humidity ranges: MEDIUM-HIGH confidence — native habitat climate data cross-referenced with horticultural databases. Optimal ranges well-supported; minimum tolerances are conservative estimates.
Indoor viability: MEDIUM confidence — professional extrapolations from ecology, shade tolerance, and analogous species. Pilot plantings strongly recommended before committing to full installation.
kilolux-hours (klxh) = instantaneous illuminance (klux) integrated over the daily photoperiod. At the 15-hour design photoperiod used throughout this study: klxh = klux × 15.
Conversion to DLI: Under sunlight spectrum, 15 klxh ≈ 1 mol/m²/day DLI. Under artificial LED (3500–4000K), 15 klxh ≈ 0.75–0.9 DLI due to lower photosynthetic photon efficacy.
Source methodology note: DLI minimums are derived from ecology/forestry literature (outdoor PAR sensors); klux minimums are from interiorscape literature (indoor lux meters). These are independently sourced and may not perfectly reconcile through the 15h conversion shorthand.
Reference Library
Curated links for species research, lighting design, and biophilic precedents.