What You Need: The Basics
While there are a few different types of aeroponics, the concept is consistent, so there will always be some similarities in the basic setup. You can start here with your shopping list once you’ve determined where your system will be located and how many plants you plan to support so that you can estimate sizes. Once you’ve got your list in hand, head to the store! For most of it, a general home improvement store will work, while pumps and tubing may need a pond store or a specialized tool store like Harbor Freight or Northern Tool. If you like to research questions on your own, then online options can be really convenient.
Ready to start shopping? You’ll need:
- Two watertight, opaque containers. One will hold nutrient solution, often called a reservoir. The other will serve as the root zone chamber. In both cases, you’ll want to prevent light from reaching the roots and nutrient solution where it could trigger algae growth. Opaque containers are a good option, or you can design a covering to enclose your containers. Both containers should have lids to maintain a closed system, but the root zone chamber, in particular, needs to be able to keep out pests and potential diseases, while still allowing oxygen to reach the plants’ roots and leaves.For both the reservoir and the root zone chamber, select a container that can withstand constant exposure to water and high humidity. Additionally, if you’ll be growing foodstuffs, seek out container options that are certified for potable water components (NSF/ANSI 61). This avoids the risks common to many plastics of chemicals leaching from the plastic into the water. You don’t want your nutrient solution to absorb phthalates or other toxic substances, only to be sprayed on your crops, especially since aeroponics practices make those impurities especially easy to absorb.
- A nutrient pump. This will be secured to the bottom of the reservoir and used to pump nutrient solution to the spray nozzles. The type of pump you choose will dictate exactly how the system works. The choice of pump is probably the most important decision you’ll make in setting up your system. It may help to take a look at the discussion below under Low Pressure Systems to understand your options. Low pressure pumps like the ones used in backyard ponds are pretty inexpensive, but you’ll get the best results with the extremely fine mist generated with high pressure pumps. Keep in mind that whichever pump you go with, water pressure drops as the number of spray nozzles increase. Therefore, the more plants you’ll be supporting, the higher pressure your pump needs to provide. When in doubt, always go for the more powerful option, since it’s cheaper to dial down the pressure than to upgrade to a stronger pump.
- Mist nozzles. The specific nozzles and sizes you need will depend largely on the pump you choose. Low tech systems use low pressure pumps and create droplet sizes over 50 microns (about the diameter of a human hair). When it comes to droplets size, smaller is better, so choose the smallest nozzle that your pump can manage. High pressure pumps can manage droplet sizes between 5 and 50 microns, which is ideal for rapid absorption of both water and nutrients.
- Tubing. You’ll need to use flexible tubing to connect your pump to the mist nozzles. Once you’ve decided how to configure your setup (flat, slanted or tower arrangements, for example), calculate your tubing lengths accordingly.
- Plant supports. With no growth medium for roots to grasp onto, you need to provide a system that is flexible enough to adapt as the plant grows, and strong enough to support the plant without damage. Depending on the mature size and weight of your crop you may opt for a simple foam collar that holds the stem, or net cups that can provide support for the weight of the plant without crowding or limiting root growth. In either case, the supports are inserted in holes in the root zone container’s lid, often with a collar that helps maintain a water barrier.
- Timer. Because the goal is to maximize the roots’ exposure to oxygen, the overall goal in aeroponics is to deliver nutrient solution only periodically. The duration and frequency of those misting periods depends on the droplet size and how efficiently the roots can absorb them. So that very specific (and brief) watering intervals can be maintained 24/7, a timer (preferably a cycle timer) should be used to turn the pumps on and off. This is less of an issue in low pressure aeroponics, since the larger droplet sizes mean that spraying may be constant.
Consider Vertical Aeroponics
Vertical aeroponics are essentially the same as basic systems, except they’re much more efficient in the use of space. If you’ve only got a 10 x 10 growing area, you’ll be very limited in the amount of food you can produce on a typical flat table setup. Building your system so that you have stacked tables, or so your crops grow out from a vertical tower (think strawberry pot), you can multiply your growth area by a factor of 10 or more, depending on the height of your ceilings and your access to ladders or catwalks!
One important consideration when designing a vertical system is the availability of light. If you’re considering stacked tables, this can be a real problem unless you’re already planning on installing grow lights. Many aeroponics growers opt for a pyramid configuration or completely vertical installations, and these can be purchased in ready-made systems if you’re not big on construction. If you’re working in very limited space, such as in an apartment or a spare room in your house, vertical aeroponics are almost certainly your best option.
Cost
One of the major concerns when would-be gardeners are looking at options is the cost associated with setting up an aeroponics system. Purchasing a “plug n play” LPA system can cost hundreds of dollars, and costs quickly multiply into many thousands of dollars once you start considering HPA or fogponics systems. However, it’s important to weigh the initial expenditure against long-term benefits such as rapid growth, high yields, and efficient use of resources. If you’re going for a low-cost DIY system to start off with, do some research on specific low-pressure configurations and with careful sourcing and some good old-fashioned elbow grease, you may be able to set up a small system for as little as $100.
