To answer this question from the plant's perspective, we must first consider its origins. Your Alocasia is a tropical understory plant, native to humid, warm environments in Southeast Asia and Eastern Australia. In its natural habitat, it thrives under the canopy of larger trees, where the air is consistently moist and still. The plant's large, thin leaves are adapted to absorb ambient humidity from the air through their stomata (pores). For an Alocasia, maintaining adequate humidity is not a luxury but a core requirement for physiological processes like transpiration and photosynthesis. When the air is too dry, the plant loses water vapor faster than its roots can absorb it, leading to stress.
From the plant's leaf surface, a fine mist feels like a brief, welcome rain shower. For a few minutes, the localized humidity directly around the leaf increases. This can provide temporary relief from dry air, helping to slow the rate of moisture loss through the stomata. The water droplets can also help clean dust from the broad leaves, allowing for more efficient light absorption. However, this effect is extremely fleeting. In a room with active air circulation (from fans, vents, or general airflow), the misted water evaporates quickly, often within 10-15 minutes. The plant's root system does not absorb this moisture; the benefit is purely topical and temporary. If water is allowed to sit stagnant in the crown of the plant or on the leaves for extended periods, it creates a different problem.
This is the primary danger from the Alocasia's point of view. Its large leaves often grow in a way that forms a central "crown" or vase-like structure. If you mist from above, water readily pools in this crown and at the base of the leaf stems (petioles). This constant moisture creates the perfect environment for pathogenic fungi and bacteria to thrive, leading to crown rot, stem rot, or leaf spot diseases. These conditions attack the plant's vital tissues, disrupting its vascular system and ability to transport water and nutrients. For an Alocasia, a case of crown rot is a severe, often fatal, health crisis that is much more detrimental than the slow stress of low humidity.
Your Alocasia would communicate a preference for a stable, consistently humid environment rather than short, sporadic bursts of moisture. There are several methods that create this stability without the risks associated with misting. Grouping your plants together is highly effective; as they collectively transpire, they create a localized humid microclimate. Placing the plant's pot on a pebble tray filled with water (ensuring the pot sits above the water line) provides constant evaporation right around the plant without waterlogging the soil. For the most significant results, especially in very dry homes, using a small humidifier is the optimal solution. It reliably elevates the humidity in the plant's immediate vicinity for hours, closely mimicking its natural habitat and allowing it to function at its best.
