I recently built an aeroponic system and am lacking just the timer. The website I got the plans from suggested an NFT-2 timer that would be on for three minutes and then off for five minutes. These timers are quite expensive for me since I spent most of my money on parts for the system. I found a 24-hour timer with 48 on/off switches that was more in my price range. Is it worth the money for the NFT-2 timer, or will my plants do OK using the 24-hour timer with 48 on/off switches?
Aeroponic systems irrigate roots that are hanging in air using a very fine mist. The roots must be kept moist at all times. The air that they are hanging in supplies the roots with oxygen. The 30-micron mist water particles sprayed from a mister are large enough to stick to the roots and keep them moist. However, they require frequent misting because there is not enough ambient moisture in the air and the liquid water particles floating in the air are too small to adhere to the roots.
With a three-minute time interval (three minutes on and three minutes off), the roots are constantly irrigated but come into contact with air and have access to copious amounts of oxygen. Several gardeners reported using shorter intervals to as short as 30 seconds on and 30 seconds off.
Longer intervals such as 30 minutes on and 30 minutes off will result in the plant roots drying during the dry interval. This will result in stunted growth or death.
A short interval timer is a tool that you need. Buying it is a one-time cost. When you consider its cost over its lifetime of use, you will find the expense insignificant. Spring for the right tool.
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