HR-15 HUMIDIFIER

Description

HR-15 Humidifier is a compact ultrasonic humidifier designed to raise relative humidity levels in grow tents and indoor growing spaces during the vegetative stage and propagation phase. We have been recommending humidifiers to UK growers since 2017 as an essential piece of environmental control equipment — particularly during winter months when indoor heating systems can reduce ambient humidity well below the levels young plants and cuttings need to thrive.

Why Vegetative Plants and Cuttings Need Higher Humidity

During vegetative growth, plants transpire water vapour through their stomata as part of the photosynthesis and nutrient-uptake process. If ambient humidity is too low, excessive transpiration occurs which causes plants to close their stomata and slow down growth to conserve water. Young plants and unrooted cuttings are particularly vulnerable — they lack the root system to replenish water lost through the leaves, making high humidity (75–85% RH) essential during the rooting phase.

The HR-15 uses ultrasonic vibration to produce a fine cool mist that disperses readily through your grow space without significantly raising temperature — an important advantage over warm-mist humidifiers that can push grow room temperatures above optimal levels. The compact design fits easily into or alongside standard grow tents without taking up valuable growing space.

Operation and Settings

Fill the water tank with clean, preferably RO or low-mineral water to prevent white mineral deposits on leaves and growing equipment. Set output level using the adjustable control dial and position the mist outlet to direct humid air into the growing area. Monitor RH using a hygrometer and adjust the output level as needed to maintain your target humidity range.

Pair with a ThermoPro TP358 or similar thermo-hygrometer for accurate RH monitoring, and a quality inline fan speed controller to balance humidity levels with extraction rate. Reduce humidity as plants progress into flowering to minimise mould risk. An important environmental control tool for propagation and vegetative growing environments.