Golden Fern - Indoor Plants Provide bright, indirect light. They don't tolerate direct sunlight well. Ferns prefer high humidity. You can increase humidity by misting the plant, placing a tray of water near it, or using a humidifier. They thrive in temperatures between 60-75°F (15-24°C). balanced liquid fertilizer every 2-4 weeks during the growing season (spring and summer) NOTE: Images are only for representation.