Recently, due to the rise of social media posts and great success with the process, growing cannabis plants using drip irrigation may be the new standard for many indoor enthusiasts. Jumping ship from organic to hydroponics with drip lines and a pump can be highly advantageous, allowing a grower to increase yields and save time and manual labor.
In this article, I explain all you need to know about growing cannabis using drip irrigation and break down just how practical and game-changing this style of growing really is. So get ready to soak up some valuable information and learn all the ins and outs, do’s and don’ts, and pro tips for this popular hydroponic growing technique.
How does drip irrigation differ from other hydroponic methods
My step-by-step guide on how to set up a drip irrigation system
The different types of dripper heads and nozzles to choose from
Are dripper ring designs good for hydroponic drip irrigation?
How to maintain and care for your plants using a drip irrigation setup
Is it important to check the E.C. levels of the runoff solution?
What is hydroponic drip irrigation?
As organic growers, most of us can relate to the arduous task of filling a bucket of water, mixing in organic liquid nutrients, and then hand watering each pot. After a long day at work, this task can be the last thing you want to do.
Hydroponic drip irrigation eliminates your need to hand water each individual pot and ensures your plants are fed at the exact same time each day without your presence.
For the hobby home grower who balances their 9-5 job and social life with growing, the thought of not needing to be in the grow room during watering times may feel like a big weight off your shoulders. Your social calendar might begin to open up again!
Not only that, there is now room to plan short breaks or a much-needed family holiday.
How does drip irrigation work?
A hydroponic drip irrigation system connects tubes, a dripper stake, and a pump. A reservoir houses the water pump, and the nutrient solution is pumped through the tubes and into the growing medium via the drip stakes. Your pump is connected to a separate timer from your grow lights, allowing you to feed for 15-minute intervals each time.
After every watering using drippers, you will notice a small volume of nutrient solution slowly pouring from the base of the pots. This is what is referred to as “nutrient runoff.” Unless you use a recirculating drip system, the runoff nutrient solution is unimportant and can be drained away and disregarded from your trays.
The pros and cons of drip irrigation
If you are already warming up to the idea of having more free time whilst growing an elite crop, you may want to consider the pros and cons associated with drip irrigation. I personally feel everyone should enter the complex world of hydroponics and use a drip system as the first stepping stone to success.
The pros
The initial set-up expense is low compared to other hydroponic systems.
You do not need to be in the grow room to feed your plants daily.
The nutrient solution is slowly pumped out over 15 minutes, reducing over saturation.
Adding an air pump to the reservoir will increase the amount of dissolved oxygen.
Drip hydroponics utilized on a large scale saves labor, time, and water usage.
Hydroponic nutrients will produce bigger plants capable of large yields.
Plants prefer to be fed consistently, from my personal experience.
Cannabis plants can be fed multiple times daily using drip irrigation systems.
You can use drip lines for small-sized pots or large-sized pots.
With a drip system, you can use soil, coco, rockwool, and 100% hydroton.
Checking the pH and E.C. of your nutrient run-off is easy to do.
The cons
Even though the costs of a hydroponic drip system is lower than most hydro setups, wick systems are still cheaper.
Over time, dripper lines can become blocked and need cleaning.
In a worst-case scenario, water pumps can become faulty and stop working.
It is easy to overwater the plants if the growing medium has poor drainage.
The grow room can become quite messy once many drip lines are set up.
Cold temperatures can be difficult to control, especially during Winter.
You’ll need a fresh batch of nutrient solution for every watering cycle.
What is a recirculating drip system? And how does it work?
A recirculating dripper system is the same design as the above one. However, rather than the runoff nutrient solution being thrown away and discarded, the opposite occurs. The table the plants are sitting on must be slightly angled with one side raised. There should be a collection tray, allowing the nutrient solution to return to the reservoir and pump.
The pros and cons of a recirculating dripper system
I think it’s safe to say that most of us wouldn’t mind saving your costly nutrients, right? Well, for those who agree, we have the “recirculating” drip irrigation version. Albeit, that comes with its drawbacks as well.
The pros
Nutrients are reused and fed back to the plants multiple times.
Plants can become huge and produce massive yields when fed using this method.
Coco and perlite mixed at a 70/30 ratio produce excellent results with this style.
Recirculating systems are extremely practical when implemented on a large scale.
The cons
The E.C. of your nutrient solution may begin to reduce the bigger plants become.
Overwatering can occur with recirculating systems, especially with rockwool.
Water pumps can malfunction and become faulty over time.
How does drip irrigation differ from other hydroponic methods
I always think drip irrigation is the gateway to discovering the true joy of a hydroponics system. Compared to deep water culture, aeroponics, or reverse deep water culture, drip systems are easy to set up, can be implemented on a small or large scale, and only need to be working for 15 minutes per day.
Skill level
Apart from connecting tubing, drippers and placing your water pump at the bottom of your reservoir bucket or tub, there really is not much more to do. You can set the timer to feed for 15 minutes each day (preferably an hour after the lights have come on), and then, as far as maintenance goes, you are free to do other things.
Expense
Buying a good quality water pump, tubing, plastic pieces to fit everything together, and drip stakes for a 6-12 plant setup will set you back around $50-100 for all the parts and pieces. The water pump required will use around 20–30 watts of power, so it won’t really move any needles as far as electricity bills are concerned.
Maintenance
Unlike more complex hydroponic systems such as DWC, you do not need to be as hands-on in the maintenance department. Hydroponic drip systems only really need to have the reservoir filled with an E.C. and pH-adjusted nutrient solution, with an intention to make a fresh batch each feeding. Oh, and you’ll need to do an occasional rinse of the drip stakes.
Noise level
As a beginner, you will most likely only need to feed your cannabis plants once a day, for 15 minutes, using a hydroponic drip system. This means the pump will only kick on once a day for a very short duration, allowing your stealth grow room to remain silent and discreet. Compared to using noisy air pumps, drip systems can have many advantages as far as noise levels are concerned.
My step-by-step guide on how to set up a drip irrigation system
Living in the Spanish countryside, as I do, it is not uncommon to see commercial growers and farmers using drip irrigation lines to water hundreds and sometimes thousands of plants at a time. Setting up an irrigation system is simple and can be done indoors and outdoors. Below is an example of how to set up a basic drip system for 10 plants using a 50-liter reservoir tub.
What exactly will I need?
9-12 mm tubing
Submersible water pump (400L/h)
Dripper stake (10 pack)
Polyethylene pipe (16mm)
Irrigation hole puncher
15-minute segment timer
A pair of sharp scissors
50-liter tub
Step 1
Sit the submersible water pump at the bottom of the 50-liter tub and make sure the bottom is firmly gripped to the base.
Step 2
Cut the 16mm pipe to the length required and insert the 16mm pipe firmly into the water pump. Make sure the fitting is tight and secure. Bend the end of the pipe to make a flat fold and tie it with a cable tie.
Step 3
Using the irrigation hole puncher, make 10 holes (2 inches apart from one another) in the 16mm pipe (connected to the pump). These holes will be where you insert the 9-12mm drip lines into.
Step 4
Cut the 9-12mm drip lines 120 cm in length. Each pot will require one dripper stake. Ensure that the lines are the same length, so cut 10 pieces.
Step 5
Now, connect the 10 dripper stakes to the 10 pieces of 9-12mm tubing. Double-check that all tubes are secure and avoid any loose fittings. Insert the stakes 1 inch deep in your growing medium.
Step 6
Now it is time to insert the 10 pieces of 9-12mm tubing back into the connecting 16mm polyethylene pipe. You will want to cut the tips of the tube at a 45-degree angle, creating a pointed part.
Step 7
Once you are happy with the secure fitting of the tubes and drip stakes, you can fill up your 50-liter tub and get ready to test drive your new drip system.
Step 8
Connect the pump to your timer and set the pump to turn on for 15 minutes once a day! Now, it’s a matter of keeping your reservoir topped up with fresh nutrient solution. It really is as simple as that.
The different types of dripper heads and nozzles to choose from
Over the years of growing cannabis using hydroponics, I have tried all types of dripper systems and experimented with feeding times, volume of nutrient solution, and various dripper heads. Not all irrigation systems use plastic drip stakes. Below are a few of the different dripper heads (some call them drip emitters) and nozzles you may want to try.
Traditional dripper stake
Example of traditional dripper stakes for growing weed plants
These lightweight plastic stakes are what the dripper tubes connect to and are traditionally the most popular choice for drip systems. They are easy to insert into the growing medium, allowing nutrient solution to slowly drip down, and will cost around $0.50 each from your local garden center.
Auto-regulated dripper
Example of Auto-regulated dripper for growing marijuana plants
These rounded types of drippers are designed to produce a set amount of nutrient solution ranging from 4 to 8 liters per hour. Unlike the stake design, auto-regulated drippers will sit above the top of the growing medium and drip downwards.
Spider design irrigation kit
Example of Spider irrigation for growing cannabis plants
I have noticed more and more home growers using these clever time-saving gadgets. The spider dripper design is simply a ready-to-buy part that can be connected to your pump and accommodates up to 12 plants.
Diffuser spray nozzles
Example of Diffuser spray nozzle for growing weed plants
These are an excellent way to provide oxygen and nutrient solutions to the plant roots. Spray nozzles cost very little and can spray in 180 or 360-degree motion. Like the auto-regulated dripper, you will need to stand the nozzle so they are not touching the growing medium.
4 irrigation systems that don’t need electricity
You can still enjoy the benefits and reap the rewards of hydroponic drip systems without electricity. Below are four solutions for a grower who wants to incorporate drip feeding into their garden and step outside the norm.
Irrigation gravity kit bag for 6 plants
Explanation of how the Gravity Bag irrigation setup works for marijuana plants
I must admit, I have bought quite a few of these cheap and cheerful gravity-designed kits over the years. The kit comes with 6 adjustable drippers, 5 meters of tubing, and connector T pieces to connect to the bag and drippers. It can hold 10 liters of water. The cost of these handy little kits is around $20-30 dollars.
Battery-powered digital irrigation controller
Explanation of how the Digital controller irrigation method works for marijuana plants
Battery-powered digital controllers are available in garden centers; they connect to a hose pipe and drip lines when watering cannabis plants outdoors. You can customize these impressive gadgets to adjust the watering frequency and volume of water given each feeding. They are a great investment for any outdoor grower.
Irrigation bottle caps
Explanation of how the Bottle caps irrigation method works for marijuana plants
Available to buy online for up to $20 for a pack of 12-30, these easy-to-fit bottle caps are designed with a long and narrow spout, allowing drops of water to pour out. All you have to do is fill your water bottle up, screw the cap on and turn the bottle upside down and set it in place. I am a fan of anything that reduces plastic waste, and these irrigation bottle caps are innovative, cheap, and effective!
The old-school plastic bottle method
Explanation of how the Plastic Bottle irrigation setup works for marijuana plants
You can always just go old school and pierce a 2.5-liter plastic bottle at the neck in two places to ensure a steady flow rate of water drips out. Making holes with scissors may not produce the most efficient design; however, it will still serve its purpose as a type of drip hydroponics.
Are dripper ring designs good for hydroponic drip irrigation?
Explanation of how a dripper ring irrigation system works for weed plants
I personally think drip rings are the elite design and allow for an even disbursement of nutrient solution around the growing medium. I would strongly recommend making your own drip ring design using tubing, connecting with a T piece, and then making small holes.
DIY dripper rings can be customized to cover any pot size.
Dripper rings are perfect when using 100% hydroton as a medium.
A growing medium can be evenly saturated compared to a dripper stake.
Ready-to-buy drip rings are well-built and work wonderfully.
How to maintain and care for your plants using a drip irrigation setup
Now that we have covered the basis of hydroponic drip irrigation and how it works, we can get into the nitty-gritty and discuss how to maintain your plants using it. There is no set way to grow using dripper systems, and thanks to the diversity of hydroponics, choosing which growing medium will be best suited for your needs is down to you.
Growing cannabis using coco with drip irrigation
Coco is a soft, airy, user-friendly growing substrate made from washed and treated coconut husks. Due to the excellent wicking characteristics associated with coco, many growers find that drip systems and coco go hand in hand. Mixing coco and perlite together will increase the capillary action, increasing the dry periods between feeding.
The benefits of using coco
Coco can retain a high volume of water and still contain lots of air pockets.
Overwatering with coco is difficult due to its structure and airy texture.
Coco is classed as an inert medium, meaning it contains no nutrition for the plants.
You are in charge of exactly how many nutrients the plants receive using coco.
It mixes very well with soil, compost, and perlite to increase oxygen around the roots.
Growing cannabis using rockwool with drip irrigation
Rockwool comes in 4-inch, 6-inch, or 1-meter slab sizes and is used worldwide for commercial-scale farming. This inert growing medium allows you to provide nutrients to the plants, producing fast root growth and nutrient uptake. You can add Rockwool cubes to the meter-long slabs and trays with drip lines inserted into them.
The benefits of using rockwool
Rockwool is highly porous and capable of holding 80% water content.
Rockwool is lightweight and easy to transport once dry.
For rooting clones, rockwool cubes are a popular choice.
Growing cannabis using 100% hydroton with drip irrigation
I absolutely love to grow using hydroton and a recirculating drip irrigation design, as you can leave the pump on 24 hours a day and never need to worry about over-watering your plants. Hydroton clay balls are specially designed for a hydroponics drip system and are commonly mixed with coco for additional drainage.
The benefits of using hydroton
Hydroton clay balls provide lots of air inside the pots.
They work especially well with drip rings.
It is not possible to overwater the plants.
Hydroton encourages explosive root growth.
Hydroton contains no nutrients and is reusable.
The pH of hydroton is neutral (pH 7)
Growing cannabis using soil with drip irrigation
You may read this far and think, “I like the concept of drip irrigation and that I do not need to hand water my grow room each day, but I’m not ready to go full hydroponic.”
Don’t worry; you can still incorporate a dripper system into your organic garden, but you can only feed plain water or an enzyme solution. Any attempt at feeding a thick and gloopy organic liquid to your reservoir and the pump will only result in blocked drip lines and a smelly reservoir.
Want to start as soon as next week with your own drip irrigation grow? Get one of our seedpacks from our deals below!
Is it important to check the E.C. levels of the runoff solution?
The short answer is yes. A good habit to develop when growing cannabis using a drip system is always checking your E.C. levels using a digital pen. The electric conductivity of your nutrient solution will indicate the strength of the mixture, and based on that value, you will see how many nutrients the plants are using.
It is common practice for growers to collect a sample of the runoff solution and check the pH and E.C. During the flowering cycle when plants are firing on all cylinders, E.C. levels can be significantly increased to accommodate the demand for primary and trace elements.
How to properly clean hydroponic drip systems
How well you look after your equipment will play a major role in the longevity and efficiency of your irrigation system. Over time, salts (found in hydroponic nutrients) can gather inside the pipes and cause blockages.
Taking apart your drip lines and connector parts and soaking them in 3% hydrogen peroxide is a great way to clean out the inner parts of the tubes. A strong enzyme solution will also serve its purpose and clean the water pipes properly.
Once you have reassembled the lines, you can then fill the reservoir, add more hydrogen peroxide, and allow the solution to circulate through the pipes and pumps. Doing so for one hour will ensure a thorough cleaning and dislodge any undissolved salts.
My top tips for using hydroponic drip irrigation
Top tip #1 – Increase feeding times during flowering
As your cannabis plants get used to being fed at the same time each day, the bigger they get. This will lead to an ability to uptake more nutrients. Increase the amount of times you water the plants from once to twice a day during the flowering stage (12/12). I personally find leaving 5 hours between feedings will produce the best results.
Top tip #2 – Back up the water pump
One thing I cannot stress enough how important it is to have a spare pump lying around, ready to save the day in the event of an emergency. I have had water pumps flood themselves, stop working, or just struggle with pressure over time. Buy two pumps and keep the spare close by!
Top tip #3 – Always clean after every harvest
Now, just because your new drip irrigation system has taken the stress and strain out of hand watering doesn’t mean you can neglect the maintenance aspect. One of the main incentives to use dripper systems is minimal maintenance, so deep cleaning your equipment with a peroxide bath is not too much to ask. Clean your system and grow room after every harvest.
Mistakes to avoid using drip irrigation
As Murphy’s Law states, “All that can go wrong…will go wrong! ”. When we are talking about drip irrigation, it is easy to make mistakes as a beginner grower. Below are a few mistakes you can avoid when using a hydroponic drip system.
No runoff at the base of the pots
When you notice no or only a minimal amount of water (runoff) coming from your pots’ base after watering, that is a sign that the nutrient solution isn’t washing all the way through from the top to the very bottom of the pots. It becomes easy for undissolved salts to accumulate in the growing medium when this happens. Avoid watering without any runoff at the base of the pots, and use enough volume until you see plenty of water coming from the base of your pot.
Cold nutrient solution
If you have ever mixed a nutrient solution using hydroponic nutrients and, after stirring things around, noticed the liquid had a cloudy consistency, this is a sign that the nutrients cannot fully dissolve. To the untrained eye, you can easily think there is a problem with the nutrient bottle itself.
To solve this issue, you only need to maintain a consistent temperature in the reservoir of 65-72 degrees Fahrenheit (18 °C – 22 °C), which can be done using an aquarium water heater.
Not checking E.C levels
The art of hydroponics is to find a balance between plant productivity and nutrient uptake. You will need to take a systematic approach and slowly increase the E.C. levels each week or increase the watering frequency daily. Not checking your E.C. levels between feeding is not advised and will never allow you to know the sweet spot, potentially causing lower yields.
My final thoughts on using hydroponic drip irrigation
Drip irrigation is certainly the first step into the complex world of hydroponics. What I really enjoy about the simplicity of hydroponic drip systems is how they can be applied to organic methods. And it eliminates hand watering indoors and outdoors.
Over the years, Coco and Perlite have always been my winning formula. However, you can always make your own custom blends with coco, perlite, hydroton, vermiculite, and rockwool. I do believe that growing cannabis using rockwool can be the most challenging.
This is something that you should work yourself up to. Especially after a couple of coco-only harvests and reading Robert Bergman’s Grow Bible.
Maintenance is as easy as it gets with drip irrigation systems; however, keeping on top of your pH and E.C. levels plays a crucial role in nutrient uptake. Always clean your drip lines, pump, dripper heads, and spray nozzles after every harvest, and remember…cleanliness is next to godliness!
Comments