Choosing a Location for Your Hydroponic System
Choosing a suitable location for your hydroponic system is one of the most important steps toward success. Here are the primary factors to consider.
The environment of the location is the primary concern. If the environmental conditions of your grow area are off, it can greatly hinder or stop plant growth. By “environment”, I am referring primarily to the temperature and relative humidity of the surrounding air. With hydroponics, we want to create an environment that matches that which the plants naturally grow in. We are providing them water and nutrients through the nutrient solution and light for photosynthesis from a grow light. We also need to provide an area with the right temperature and humidity. Fortunately, plants and humans have a lot of similarities in this regard.
Many greens are considered a cool-weather crop, where they have their best growth and flavor during cooler seasons (spring and fall). Some greens, such as lettuce, will turn bitter if they get too hot. So one of the primary considerations is keeping the temperature from getting too hot. What is too hot? Well, in my experience, the ideal temperature range for most greens is 60-75 degrees F. Some plants and varieties are more heat tolerant than others and can withstand temperatures higher than this, but this is the ideal range. Temperatures below this range are ok (kale in my outdoor garden grows right up to the first frost, or even past it!), but plant growth rate will slow.
Nutrient solution temperature is also very important. When the temperature of the nutrient solution increases past 70 degrees F, it increases the likelihood of disease or fungus, including root rot. Dissolved oxygen, which is important for plant root health, also drops as water temperature increases. A good target for nutrient solution temperature is 60-70 degrees, similar to air temperature. The nutrient solution is often naturally a few degrees less than air temperature since it is near the ground, so that can work out nicely.
Relative humidity determines the evaporation rate from the plant leaves. This has a large impact on the plants, because that evaporation is what pulls new nutrient solution up through the roots and into the plant (transpiration). There is a lot of detail in that process, but a general rule is that most greens are happy between 40% and 60% relative humidity, very similar to the ideal range for humans and homes.
Another consideration is water access. To make nutrient changes easier, it is helpful to have a water source and a drain nearby. If easy water access isn’t feasible, you always have the option to use an affordable submersible pump with a long tube to move water back and forth between your system and the sink/drain, so this is certainly something you can work around.
Consider the effect the system will have on your living space. The grow lights will be on during most waking hours. This can be nice if you want to light up a dark area, and it wouldn’t make much of a difference in a low-traffic area, but it wouldn’t be great next to a TV, etc.
Also, the system contains water, so be prepared for drips. The hydroponic system should be leak-proof once its fully constructed and tested, but you will still have drips when harvesting plants or doing water changes. This can be greatly minimized by taking your time, but I wouldn’t recommend placing your system above a new white carpet. You get the idea.
There are a lot of great potential growing locations depending on your situation. The easiest and most common is a basement, if you have one. Basements are often naturally cool and have water and/or drain access. Also, in my experience, it’s really nice to have some extra light and bright green growth in a basement!
But if you don’t have a basement, no worries! An unused portion of just about any room can work well. Since ideal conditions for humans closely match what the plants need, most locations within a home should work well if you are willing to use them. Previously, I set up a large hydroponic system in an unused corner of my 4-season porch. The porch had no A/C, so during the summer the room would get warm during the day (over 80 deg F in some cases). However, the temperature would come back down during the night and most plants were still happy.
You could also do seasonal hydroponics in a garage or outdoor structure. Run the system during ideal times (i.e. fall-winter-spring in a hot climate, or spring-summer-fall in a cold climate) and shut it down at other times.
Once you choose a location and clear it out, you’re ready to design and build your hydroponic system!