The short answer
Misting is not a reliable way to raise humidity around a calathea. A humidifier and protection from drying drafts are more effective than frequently wetting the leaves.
Why this happens
Mist evaporates quickly, so any humidity increase is brief. Wet foliage and poor airflow can also encourage leaf disease. Calatheas prefer evenly moist, aerated soil rather than saturated soil.
What to do
- Measure room humidity if possible.
- Keep the plant away from heating vents and air conditioners.
- Use a clean humidifier if the air is consistently dry.
- Check soil moisture separately; humidity does not replace root watering.
Keep in mind
Crispy edges can also come from water quality, excess fertilizer, or dry soil. Do not assume every brown edge means low humidity.