Light exposure levels are defined by the duration and intensity of direct sunlight received by a plant during the peak growing season. Botanical standards categorize these levels based on hourly thresholds and qualitative light characteristics.
| Classification | Direct Sun Duration | Characteristics |
|---|---|---|
| Full Sun | 6+ Hours | Requires at least six hours of unobstructed, direct sunlight, including the peak intensity hours of 10:00 AM to 4:00 PM. |
| Partial Sun | 4–6 Hours | Requires a minimum of four to six hours of direct sun; often prioritized for plants needing higher light intensity to produce flowers or fruit. |
| Partial Shade | 4–6 Hours | Similar duration to partial sun but emphasizes protection from intense midday and afternoon rays; prefers "cool sun" (morning light). |
| Full Shade | < 4 Hours | Less than four hours of direct light; often relies on dappled or filtered sunlight through a canopy or reflected light. |
| Dense Shade | ~0 Hours | No direct sunlight; typically found under dense evergreen canopies or the north side of tall structures. |
Light intensity measures the amount of light falling on a surface and is critical for determining indoor placement.
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https://houseplantresourcecenter.com/2020/03/houseplant-basics-how-to-determine-how-much-light-you-have/