How To Grow Marijuana Hydroponically
As you consider what type of permanent marijuana growing system to set up, you’re going hear a lot of talk about hydro-systems and hydroponics. The term “hydroponic” liter- ally translates as “water work” and refers to a specific method of metabolism where a plant absorbs all nutrients through a soil-less medium. This doesn’t necessarily mean all hydroponic plants grow in a glass of water. In the last 20 years, advances in hydro- technology have allowed growers to create growing beds out of everything from plastic baskets to blocks of rockwool insulation.
In order to thrive, a marijuana plant only needs: water, light, oxygen, nutrients, and carbon-dioxide. Plopping a seed down in a plot of dirt is the “tries and true” way to meet these demands, but that doesn’t mean it’s necessarily the most efficient method. The main principle behind hydroponic farming is the idea that a plant which does not have to expend energy searching for nutrients in soil will instead allocate those resources to fruit and leaf production. Rather than rely on fertilizers to ensure plants have the nutrients they need to thrive in a plot of soil, hydroponic farmers create “nutrient solutions” which are directly applied to the root system itself. Download my free grow guide for more information about growing marijuana hydroponically.
Because marijuana plants can use nutrients as soon as they are absorbed, cannabis often grows extremely fast in soil-less gardens. That being said, hydroponic systems require a high level of research, maintenance, and overall investment. They can also be more unforgiving of mistakes made while trying to learn how to manage your system.
Personally, I have found that the best way to be a single, self-sufficient grower, is to go back to basics – pick up your seeds and get ready to get hands dirty. However, no “how to grow” your manual would be complete without a section on hydroponics. Below is a brief overview of the several methods for hydroponic growth. Before you decide to set up a soilless system, research your local vendors to make sure you have the resources and space necessary to set up a hydro-system.
Five Soilless Systems
Generally, hydroponic systems actually use less water than soil-based systems. However, if you’re setting up a hydro-system you’re going to have to encounter all the costs that come with setting up an indoor growing environment. In addition, you may find yourself spending more money on fertilizers and growing mediums. Nutrient solution mixtures will be an additional, but completely justified cost, as well. Luckily, hobby hydroponics has taken off in the past ten years and numerous online vendors can offer competitive prices for everything from supplies to complete soilless systems. However, before you spend any cash, you’ll want to have a basic hydroponic vocabulary so you can shop intelligently.
- Deep Water Culture (DWC)
This is one of the easiest systems to build and maintain. The investment is minimal, and the general rule of thumb is one unit per plant. In its most basic form a DWC consists of three parts. The first piece is a light-sealed reservoir where the nutrient solution is stored (protection from light ensures algae and other impurities won’t be able to grow and pollute the solution). The second section is usually a small bucket or net filles with a growing medium (rockwool, perlite etc.) which hangs above the nutrient solution. Think of a 5 gallon bucket with a perlit-filled basket suspended from a hole in lid. It’s vital that the second piece be made of a mesh or porous material so that the roots can grow down towards the nutrient solution without being hemmed in. The final piece of the DWC setup is an “airstone” placed within the nutrient solution itself. “Airstones” can be found in any pet supply store near the aquarium section. Used in fish tanks, airstones naturally release oxygen into any water based solution.
DWC systems are hydroponics at its most basic. The advantage is a rich and easily accessible supply of nutrients for your plants. But dangers arise whenever a water source remains stagnant. Keep an eye out for root rot or parasites which can thrive in nutrient rich water. Make sure each container is light-sealed to prevent algae growth.
- Top Feed
Similar to the DWC, top feed hydro-systems are fairly simple to set up and easy to maintain. As with DWC, a reservoir of nutrient solution is placed below a porous container holding a plant. The plant should be growing in a soilless medium and a hose should be placed at the base of the stalk. This hose is connected via a pump to the nutrient solution. Several times a day, a timer activates the pump and the solution is rained down over the root system. At the same time, anything not absorbed is collected as it drains from the porous and soilless medium back into the resevoir. Think of it as a fountain for your pot plant. The advantage to top feeders is that they are easy to maintain and reliable. You have the option of setting up one unit per plant, or buying pots big enough to house several small plants at once. However, your initial investment is going to be a bit more than if you were working with a simple DWC system and if your pump breaks, you have to react fairly quickly to make sure the roots don’t dry out and die.
- Ebb and Flow/Flood and Drain
The name says it all, ebb and flow systems involve soaking plant roots in a nutrient solution for a set amount of time, draining the roots, and then repeating the process several times a day. Most systems involve a water- tight table or plant bed which holds several large plants growing out of blocks lockwood (or some other soilless medium). Much like the top-feeding system, ebb and flow offers the advantage of not dealing with stagnant water (which can lead to root rot, parasite infestations etc.) The disadvantages come from increased investment and multiple plant exposure. Ebb and flow systems are built to accommodate more than one plant at a time. If your solution needs tweaking, or a parasite has entered the water, you’re going to lose multiple units rather than just one plant.
-Nutrient Film/Flow Technique (NFT)
Effective, but equipment reliant, NFT hydroponic systems use capillary mats as the medium which connects roots to the nutrient solution. Most NFT plants are sprouted normally, but the seedlings are then suspended so that the roots enter a growing chamber which exists as a layer between the solution reservoir and the spouted plants. The bottom of the growing chamber is lined with capillary mats which are then covered in a constant flow of nutrient solution from a pump connected to the reservoir below. These mats are key to this system, and a great growing tool to keep around even if you’re growing non-hydroponically. Capillary mats are made of an extremely porous material which absorbs water rapidly but dispels liquid at a much slower and more constant rate. The advantage to the NFT system is that is regulated the roots’ exposure to liquid (preventing drowning) but still allows for 24/7 access to the nutrient solution. Unfortunately, with more components to maintain and equipment to buy, the NFT also requires a deeper investment of time and energy on the part of the growers.
- Aeroponics and Misting
Areoponics and misting can result in amazing crop yields, but the results require a lot of time, effort, and expertise. Most aeroponic set-ups are dependent on an environment which maintains close to 100 percent humidity at all times. Plants are sprouted and hung in soilless mediums (baskets with rockwool or expanded clay balls). Then as roots grow they are simply allowed to hang down- wards. The nutrient solution is misted directly onto the roots from a spraying system that is set up and timed. The key to this system is that everything below the stalk (i.e. everything that would not normally grow above the soil) hangs into a sealed environment where the nutrient solution sits and where the misting system has direct access to the roots.
Misters draw enriched moisture from the reservoir and anything not absorbed by the roots is allowed to circulate in the artificial environment. Problems arise when rapidly growing roots crowd out smaller roots resulting in uneven distribution. In addition, self-sufficient mister system don’t come cheap and can break easily. Salt buildup from the nutrient solution can cause problems with nozzles. If something goes wrong you have to open the entire unit, and you risk drying out your plants. In general, areoponics is a great system (both NASA and Disney actually use it to grow food supplies), but it is not necessarily the best for a small grower whose goal is to create a personal supply of pot.
The major challenge in hydroponic farming is deciding how you’re going to deliver nutrients to your crop. Luckily, marijuana requirements do not change whether you’re growing in soil, sand, or solution. Overall, making a nutrient solution is fairly simple – most hydroponic suppliers sell solutions that are already mixed and only need water. However, since you’re working directly with root absorption, you are going to need to pay attention to the PH balance of your solution more than if you were working in soil.
Because your marijuana will be growing faster in a hydro-system, the consequences of an imbalances solution will build up much faster than they would if you were working with soil. Weed likes to grow in slightly acidic mediums. You’re going to want to test your water, and then test your mixed solution every day, and especially before you apply it to your crop. Most growers recommend keeping your PH somewhere between 5.5 and 6.8; the ideal lies somewhere in the middle around 6.15. If you find your solution is too acidic or too basic you can easily buy products specifically designed to raise or lower the PH levels of your plant food without causing unwanted side effects.
- More Research
Hydroponic growing requires a significant support system and almost constant availability (in case something goes wrong). Before you decide to invest ask yourself several questions to decide if this is the right system for you:
- Do you have the space for a grow room that will require a constant flow of water?
- Are you willing to pay electrical bills for grow lamps, heated water, and equipment (timers, pump etc.)?
- Are there suppliers nearby where you can re-stock if something goes wrong or are you dependant on internet vendors?
- Are you willing to keep track of minute details on a day to day basis (pH balance, water levels, nutrient imbalances etc.)?
- How much research have you done on the specific system you’ve chosen to work with? Are there sources you can turn to for troubleshooting or if something goes wrong?
In the past most hydroponic growers were commercially based. Elaborate systems were set up and maintained in order to yield large crops that could be harvested and sold for profit. However, in the past ten years hydroponics has become a hobby sport for gardeners who cultivate everything from weed to tomatoes and herbs. Entire kits for individual hydro-growers can be bought at almost any major gardening supply company in the U.S. If you’ve never grown pot before, soil may be the best way to start learning the ins and outs of marijuana cultivation. If you’ve already cultivated a few plants and feel confident enough, then hydroponics may be the best next step for your garden.
If you want start growing, download my free grow guide and order some marijuana seeds at this link here. We ship seeds to the US, CA and many other countries. For any growing related question please visit the marijuana support page.
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