Too much direct sunlight (especially the midday sun in summer) can also damage plants, mainly manifesting as "sunburn":

Leaf scorching: Brown, yellow, or white dry spots or edges appear on the leaves. These spots are irreversible.

Leaf discoloration or whitening: Strong sunlight can "bleach" leaves, causing them to lose their original bright green color and appear white or yellowish.

Leaf curling or drooping: To reduce the surface area exposed to light, the plant's leaves may curl inward or droop downward. This is especially noticeable at midday and is sometimes temporary wilting, but if the sunlight continues to be too strong, it can cause permanent damage.

Soil drying out quickly: The soil in the pot becomes very dry within a day.

How to easily test light levels:

Hand shadow test: At the brightest time of day (e.g., midday), place an outstretched hand where the plant is located.

Observe the sharpness of the shadow:

Sharp and clear shadow -> Strong direct sunlight (suitable for most flowering plants and succulents). Blurred shadows but discernible outlines -> Medium light (suitable for many foliage plants).

Almost no shadows -> Low light (suitable only for a few shade-tolerant plants).

Understanding the Plant's Native Environment

Sun-loving plants (e.g., succulents, roses, jasmine, mint): Require at least 4-6 hours of direct sunlight.

Neutral plants (e.g., pothos, spider plants, monstera, peace lilies): Prefer bright, indirect light; avoid strong direct sunlight.

Shade-tolerant plants (e.g., snake plants, cast iron plants, dwarf coconut palms): Can tolerate lower light levels, but not completely without light.

Summary and Recommendations

Observe carefully: Develop a habit of regularly observing your plants; they "speak."

Gradual adaptation: When moving plants (e.g., from indoors to outdoors, or from low light to high light), allow for a gradual adaptation process to avoid stress caused by drastic environmental changes.

Regularly rotate the pot: For indoor plants, rotate the pot a quarter turn each week to ensure even light distribution and prevent excessive tilting to one side. By combining the above observations and methods, you can accurately determine whether your plants are receiving adequate light and adjust their placement accordingly to ensure their healthy growth.