How do coastal plants in the Namib Desert obtain moisture from fog?

In the Namib Desert, coastal plants rely on moisture derived from frequent fog to survive in an otherwise arid environment.123

While the exact mechanisms can vary by species, the process generally involves the following:

• Direct Absorption: It is hypothesized that plants such as the welwitschia (Welwitschia mirabilis) may collect moisture from the desert's frequent morning fog on their leaves, which then enters the plant tissue.4
• Succulent Adaptations: In the coastal region, highly succulent vegetation—including various shrubs and aloes—is specifically adapted to utilize fog-derived moisture to sustain life despite the lack of significant rainfall.23
• Fog Drip: In broader ecological contexts, plants can also benefit from "fog drip," where water droplets from drifting fog collect on surfaces (such as leaves) and subsequently drip to the ground, providing essential hydration to the soil and root systems.5

Although these adaptations are critical for survival in the Namib, the specific physiological processes for many of these plants remain a subject of ongoing scientific study.4