Fail-Proof Guide to Germinating Seeds in Hydroponics Plus, How to Care for Hydroponic Seedlings… We have a cannabis seedling germination page which has everything you need to know about all How to grow cannabis seeds hydroponically is a promising solution to many challenges of cannabis crop production. Buy Feminized Seeds. Find out exactly why these 5 cannabis seeds will deliver exceptional results in a hydroponic grow system
Fail-Proof Guide to Germinating Seeds in Hydroponics
Plus, How to Care for Hydroponic Seedlings…
We have a cannabis seedling germination page which has everything you need to know about all the different germination methods, but this tutorial is different. In this hydroponic seedling tutorial I’m going to share exactly how I do my seeds from beginning to end in a DWC/bubbleponics setup!
Just follow these instructions and you’ll end up with healthy, fast-growing plants that germinate in just a few days. It’s pretty much fail proof!
Learn How to Start Seedlings So You Can Grow Hydroponic Cannabis Plants Like This!
1.) Get Cannabis Seeds
There are a few different ways to get cannabis seeds, with the most common being ordering seeds online and growing seeds you find in weed that you buy. Learn how to research and find the right strain.
Here’s a picture showing several healthy and viable cannabis seeds
2.) Germination for Hydroponics
I’ve tried a bunch of different germination methods over the years, and the technique I prefer is for hydroponics is starting with the “Paper towel method” to germinate, putting the germinated seeds into Rapid Rooters, and installing the Rapid Rooters directly into reservoir. Lots of other germination methods as well, but this has worked best for me!
Paper Towel Method
This method is hard to mess up if you follow the instructions!
- Place your seeds inside a folded wet paper towel, and place it between two paper plates (or regular plates) so that they don’t dry out.
- Check on your seeds every 12 hours but try not to disturb them. When they’ve germinated, you’ll see the seeds have cracked and there are little white roots coming out.
- They should germinate in 1-4 days, though some seeds can take a week or longer (especially older seeds).
- Keep them warm if possible. One thing you can do to get seeds to germinate a little faster is to keep them in a warm place (75-80°F). Some people use a seedling heat mat but in most cases that’s unnecessary.
These seedlings were sprouted using the paper towel method!
3.) Place Germinated Seed in a Rapid Rooter
The Rapid Rooter should be cut open lengthwise
Gently place the germinated seed inside, root down
Most seedling plugs will go back into place easily, and you’ll barely be able to tell it’s been opened
4.) Prepare Hydro System for Its New Guest
If you haven’t put your hydroponic system together yet, now is the time! Make sure your pumps are all running, and that you’ve made a reservoir with seedling-strength nutrients. You need a home to put your new plants!
Hydro Tips & Hints
- Air bubbles – have lots and lots of bubbles in your water reservoir. That means your air pump needs to be on all the time for the full grow. The main benefit of hydro is your plant roots are getting an unlimited amount of both water and oxygen. This is achieved by dissolving a lot of air into the water via an air stone and air pump. In order to get the fast growth, you want a lot of bubbles! A highly-oxygenated tank is also far less likely to get root rot, or suffer from other unwanted organisms growing in the reservoir! – This supplement contains a specific bacteria that was first found in rice paddies in Japan in the 40s! It’s been common in Asia for years but only in the last several years has it been available in the US from a company called Botanicare. I highly recommend, even insist, that all hydro growers get this cheap-but-effective supplement to keep plant roots healthy!
- Add seedling level nutrients from the beginning. A lot of growers, especially soil growers, will tell you not to add any nutrients for the first few weeks of the plant’s life. That makes a lot of sense in soil, because there are lots of nutrients contained in the soil itself for your young cannabis seedling, and giving more right at the beginning can end up giving way too much for such a young plant. However, in hydro, the only nutrients your seedling gets is what’s in the water, plus what little was contained in the seed itself. Because of that, I highly recommend giving seedling-strength nutrients to your plants from when you first fill your reservoir. Seedlings grow a LOT faster with light levels of nutrients than if you only give plain, pH’ed water at first. from the beginning of your plant’s life to end the of your plant’s life
5.) Install Rapid Rooter and water the seedlings until roots reach the water reservoir – Turn on light to keep seedlings warm for best results!
Make sure to always keep the Rapid Rooter moist but not soaking wet.
If you have a top-feed, place the tube near the bottom of the net pot so the water isn’t soaking the seedling’s roots. You just want water dripping out the bottom so the root can use it for oxygen and water until it’s fully established in the reservoir.
Add your Rapid Rooter(s), and fill around the edges with extra clay pellets to hold each one in place.
Since your seed has already sprouted and been in placed into the right growing position, it’ll often pop its head out within just 12-24 hours! Sometimes you see just the leaves, but occasionally you actually see the seedling push the shell above ground. I keep the grow light on even before the seedling appears. It helps keep it warm and guide it toward the light.
When this happens the shell usually falls off on its own as the seedling grows!
The Rapid Rooter in this picture is a little too wet, which makes the seedling prone to “damping off.” If you ever notice the Rapid Rooter actually looks wet or shiny, it’s too much water. Try turning the top-feed off every few hours, or hand-watering the seedling at first. Too much moisture can kill!
Don’t use a humidity dome on seedlings unless it’s very dry where you live. If you do use a dome, consider keeping a vent open and watching the humidity. A young seedling doesn’t require high humidity, and they tend to get “wet feet” and stop growing in constantly wet conditions.
Now that your seedling in in the tank, it’s time to learn how to….
6.) Take Care of Hydro Seedlings
Here are tips for taking the best care of hydroponic marijuana seedlings:
- Leave roots alone as much as you can with young seedlings in a hydroponic setup. It takes them a little while to get all established in the tank, almost like a fish, and during that time seedlings are much more sensitive to their roots being touched or being moved around. If at all possible, try to let the seedling grow in the same place without being moved for at least a few weeks until you put them in their final home, or even just start them in their final home!
- Avoid reservoir changes for a few weeks if you can – Going along with what I said before about leaving the roots alone, I’ve found that young seedlings often don’t respond well to reservoir changes. Instead of changing the reservoir, just top off with half-strength vegetative nutrient water until the plant is at least 3 weeks old. It won’t be using enough nutrients to mess with the ratios, and as long as you maintain the pH and use Hydroguard your young plant will be fine with being topped off.
- Check the pH dailyto prevent nutrient deficiencies
- Warm but not hot temperature– I recommend hydro growers aim for 75°F, and try to stay between 73-80°F.
These seedlings are a few weeks old, and the grower plans to move them all to the
This is a time-lapse video of a cannabis seedling sprouting and growing over 13 days.
Cannabis seedlings just getting their bearings – try to avoid moving or disturbing them until they are growing fast, with new leaves every day!
Big cannabis plants ready to switch to the flowering stage
I thought hydro plants liked it cold?
Just like in soil, cannabis plants in hydro tend to grow faster in relatively warm temperatures. This is a somewhat controversial statement because a lot of hydro growers prefer to keep their temperature lower in the grow space to help prevent root rot. In fact, there are some growers right now who are reading this and shaking their heads at me.
There’s good reason to believe that hydro plants would grow better with a cool reservoir. For example, the bad microorganisms that make root rot don’t survive well at lower temperatures. Additionally, water can physically hold more oxygen at lower temperatures, which seems like it would be great for faster plant growth. Because of this, lots of growers will AC their room to 60°F, and/or get a water chiller to cool their water reservoir to a similar temperature.
I do agree that if the temperature is above 80°F, your plant is a lot more likely to get root rot. However, I personally have not found that cool temperatures are adequate to prevent root rot. Even if the temperature is 60°F, you still need lots of bubbles and a “good bacteria” supplement like Hydroguard to prevent root rot in many cases.
I’ve seen several growers buy a water chiller and still get root rot. So I personally don’t believe cold temperatures are the best way to go to keep roots healthy.
The other reason I recommend to keep it warmer is because the plants just grow faster around 75°F in hydro. If your roots go from 60°F to 75°F, you’ll see the plants start growing faster in just a day or two, just like how plants in soil grow faster when it’s warm!
Just like in soil or coco, cannabis plants in hydro grow fastest when it’s a little warm, around 75°F!
Although there may be more oxygen dissolved in the water at lower temperatures, at least in my grow tent that apparently isn’t the limiting factor to growth, because plant growth speeds up at warmer temperatures.
I’ve found that if the grow space feels cool to you, it also feels cool to your plant most likely, and it may not be growing to its full potential. Some Sativa strains are particularly sensitive to the cold, though some Indica strains from cold climates will still thrive at lower temps.
Autopsy: Why Aren’t My Seeds Sprouting?
If your seeds still aren’t sprouting and growing properly, consider the following factors.
If there’s no germination at all…
- Temperature may be too hot or cold – aim for 75-80°F
- Too wet – seeds and seedling roots should always be moist, but should not stay wet
- Too dry – if a root dries out the seedling can die!
- Bad seeds – It might not be you, it could be the seeds themselves! How can I tell if seeds are viable?
If seeds sprout, but then stop growing…
- Temperature is too hot or cold – aim for 73-78°F
- Too wet – even though your plants are growing with root directly in water, new seedlings don’t like “wet feet”. They don’t like for it to be too wet near the seed for too long, so make sure your Rapid Rooter or growing medium nevers looks shiny or muddy, as that means there’s too much water! Young roots that stay too wet for too long start to get mushy and die. For this reason, it’s also usually recommended to avoid using a humidity dome with seedlings unless your air is dry. Although clones love humidity domes (they need water from the air because they don’t have any roots to get water), seedlings like it a little more dry or roots tend to get mushy.
- Too dry – less common unless you live in a very dry area, but sometimes your medium dries out too fast if you’ve got a heavy-drinking, fast-growing seedling!
- Too much light – if the seedlings get blasted with high levels of light right away, it can shock them. They may need some time to adjust to higher light levels. Simply starting your grow light a little further away that normal is usually enough.Think sunny window at first, and start ramping up after a week of healthy growth.
- Not enough light – if seedlings are growing long and stretchy without growing new sets of leaves, it means it wants more light.
- No light for more than a day – if the sprouted seed doesn’t get light within 24 hours after sprouting, it may die. Once seeds are sprouted, get them in a Rapid Rooter and under at least some amount of light as soon as possible!
- Roots damaged – If somehow your roots got damaged, it can sometimes stop the seedling from growing
Unfortunately sometimes you will never know why certain seeds just don’t thrive! It’s all part of nature
How to Grow Cannabis Seeds Hydroponically
How To Grow Cannabis Seeds Hydroponically – Hydroponic cultivation is a promising solution to many challenges of crop production. It fixes the need for arable land, deforestation, ecosystem degradation, climate changes, and other issues related to cannabis cultivation. For decades, hydroponics has proven its effectiveness in various settings, and cannabis farming is no exception.
What Is Hydroponic Cultivation?
Hydroponics is a method of cultivating plants without soil by using mineral nutrient solutions in an aqueous solvent. In hydroponic cannabis cultivation, farmers plant their seeds in inert growing media and then supply them with nutrient-rich solutions like oxygen and water. To ensure that the plants remain healthy, farmers must control the whole environment, including nutrition, lighting, temperature, humidity, and oxygen. This system encourages rapid growth, high yields, and top-quality cannabis.
How to Grow Cannabis Seeds Hydroponically
To achieve successful results in hydroponic farming, cannabis growers must become acquainted with every component that ensures a smooth and efficient hydroponic grow. This includes selecting a grow medium, hydroponic system, lighting, nutrients, and more.
Choosing a Hydroponic Growing Medium
The first step to growing cannabis seeds hydroponically is to choose a growing medium. The medium allows roots to access nutrients in the water easily. There is an array of growing media to consider, but the right medium depends on which hydroponic system you will be using. Some of the most popular media include:
Clay pebbles, also known as hydroton, are great at aerating cannabis root zones. These particles have large pore spaces, allowing the nutrient solutions to flow through the medium easily. Their large pore size also reduces the chance of blockages within the hydroponic system. Clay pebbles are set up by simply placing them in the container and creating gaps for easy root penetration into the water.
Clay pebbles are a popular choice for small-scale growers; however, this type of medium might be too costly for larger operations. Another drawback is that farmers sometimes need to adjust the pH of the medium to provide an optimal growing environment.
Made using basalt rock and recycled slag, Rockwool is a type of mineral wool that is a popular medium for cannabis cultivation. Rockwool is excellent for water retention, allowing for adequate hydration of the upper root system. This medium also provides exceptional drainage, preventing the plants from becoming overwatered. Although Rockwool is a popular medium that offers many benefits, it is not environmentally friendly and requires pH adjustment for optimal plant growth.
Perlite is a volcanic glass that expands when exposed to high temperatures. This medium is affordable and easy to use, making it a popular choice for hydroponic and soil growers alike. Perlite provides adequate aeration and prevents compaction in garden soil as well as hydroponics.
This medium does not degrade or decompose and can be reused multiple times before it starts to break into smaller pebbles. Perlite has a neutral pH and will take on the pH of the nutrient solution it is submerged in, making it easy for growers to regulate the acidity or alkalinity of their media.
Coco coir is made from the hairy fiber on the outer shell of coconuts. This type of medium allows for proper aeration and moisture retention in hydroponic systems. It also protects roots from the harsh effects of plant-stimulating hormones. Coco coir is environmentally friendly, has a neutral pH, is reusable, and does not allow for the growth of fungi.
Choosing a Hydroponic Growing System
Most hydroponic systems are similar in their use of nutrient-rich water solutions; however, they differ depending on the material used, setup, water exposure, and circulation. Still, farmers can go for DIY systems using buckets, pumps, drills, and air stones. The best hydroponic systems to consider are:
Deep Water Culture (DWC)
Deepwater culture is a cheap and easy way for beginners to grow cannabis seeds hydroponically. To set up a DWC system, growers simply place their plants in buckets filled with nutrient-rich solutions and use air pumps to supply oxygen to the roots.
Because this system does not use a growing medium, it prevents pests from proliferating around the root zone. DWC systems are fully automated and require little maintenance to use, making them ideal for inexperienced growers or those with large-scale operations.
Ebb and Flow
This system consists of buckets hung over a growing tray with inlet and outlet waterways, both of which connect to an external tank. The tank periodically supplies the plants with fresh water that is rich in nutrients and oxygen. The system has a water pump and a timer to control the water cycle to and from the external tank and growing tray. Ebb and flow systems are ideal for beginners as these systems are highly effective, easy to use, and require minimal maintenance.
Nutrient Film Technique (NFT)
With the nutrient film technique, plants absorb nutrients and oxygen from a solution that flows through growing trays. The tube that circulates the solution is tilted slightly to allow the water to flow from one side of the reservoir to the other. With this system, crops receive a constant flow of nutrients and oxygen. Growers can conserve water and nutrients by using the nutrient film technique because the nutrient solution is constantly being recirculated.
A drip system is a type of irrigation method that slowly drips nutrients and water into the roots of the cannabis plants. This system consists of a large tray with a growing medium such as clay pebbles or perlite. Cannabis plants access the constantly flowing solution through individual pipes, and the excess solution drips down the growing medium and back into the reservoir. Because drip systems slowly release water to the plants, it reduces the amount of water lost due to evaporation. This system is also very energy efficient, as it does not require a great deal of pressure from a powerful pump.
Much like drip systems, wick systems use growing trays that are filled with clay pebbles. A water tank rests underneath the tray from which several wicks connect to the medium. The solution travels down the wicks, passively hydrating the roots of the plants. This type of system is entirely passive and does not require any pumps or air stones. Wick systems allow the plants to access only as much water as they need, meaning that growers need not worry about overwatering their crops.
In aeroponic systems, plants are suspended inside of a chamber, and their roots are misted with water. Aeroponic systems are often used to start clones but can also be used throughout the entire growth cycle. This type of system may not be ideal for inexperienced growers, as it takes some expertise to set up and maintain. This system also makes it easy for pests and diseases to take hold in the garden.
In the past, most farmers preferred to use high-intensity discharge lights (HIDs) such as high-pressure sodium (HPS) or metal halide (MH) lights. But the recent full spectrum light-emitting diode (LED) grow lights have had tremendous success.
MH lights are close to natural lighting and are abundant in blue and green spectrums, which are best for vegetative growth. HPS offers orange, amber, and red-light spectrums, which are best for later cannabis flowering stages. Farmers often use metal halide lights during the vegetative growth period and switch to high-pressure sodium lights during the flowering period.
Although HID lamps provide an excellent light source for plant growth, they waste lots of energy and produce excessive heat. To mitigate the heat, farmers should invest in robust ventilation systems, including can fans and oscillating fans.
Lately, many growers have started using full-spectrum LED lights, which are far more energy-efficient than HID ones. Moreover, they are perfect for all growing phases and don’t require a ballast to power them.
Because most strains of cannabis are photoperiod-dependent, farmers should carefully regulate the light cycle during the vegetative and flowering stages. This is a crucial step in growing cannabis seeds hydroponically.
Like other crops, cannabis requires an abundance of major nutrients, including nitrogen, phosphorus, and potassium. Additionally, it requires smaller amounts of other nutrients such as boron, sulfur, calcium, magnesium. The best way to feed cannabis plants is to use hydroponic nutrient solutions containing all the required nutrients for the vegetation and flowering periods.
Best Cannabis Seeds
Greenpoint Seeds offers superior cannabis seeds that produce potent plants in any hydroponic growing system, regardless of your growing season or environment. We pride ourselves in providing the best feminized and regular cannabis seeds on the market.
Contact us for more information about how to grow cannabis seeds hydroponically. Have you ever tried hydroponics? Share your story in the comment section below.
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2 thoughts on “ How to Grow Cannabis Seeds Hydroponically ”
I use general hydro nutrients and have found that because the ppm of my water is below 50 I have to add small amounts of vsma and so to get the best results in my deep water system. A ppm meter is very important to a hydro system.
Top 5 cannabis seeds to grow in hydroponics
The majority of cannabis strains will grow well in hydroponic conditions. When cannabis hydroponics is done well, the optimised conditions offered can allow hydroponics to outstrip growth rates from just about any other cultivation method assuming other factors (lighting, nutrient management etc) are well controlled. But which cannabis seeds will really shine in a hydroponic grow and why? Which cannabis genetics have the breeding and potential to produce XXL yields of resin drenched buds? Read on to see some great pictures of the best cannabis strains enjoying life in the hydroponic fast lane.
What is hydroponic cannabis growing?
Hydroponics is a type of horticulture used for growing cannabis and other crops. Specifically, hydroponics is a form of hydro culture which involves growing plants/crops without soil. Instead the mineral content of the nutrient solution provides the necessary food for plant growth. The cannabis roots may be held in place with clay pebbles, perlite or other inert support materials and may have their oxygen needs boosted by being bathed in a stream of air bubbles.
|Expert guide to hydroponic cannabis growing|
Best cannabis strains for hydroponic growing
All the Dutch Passion cannabis strains can be grown in hydroponics with great results. But some cannabis seeds can deliver quite exceptional results when the hydroponic cannabis conditions are really dialled in and optimised. The best cannabis strains for hydroponic growing show intense growth vigour. Get the lighting conditions optimised with a high quality LED grow light and you can see branch-breaking harvests.
Of course it helps if you have the experience to maintain the plants in the nutrient ‘sweet spot’ without over-feeding or under-feeding from cannabis seed to harvest. It also helps to deliver top-shelf results if you can maintain optimised environmental conditions. Get all that right and you can see some genuinely astonishing results. The following strains come with our highest recommendations to hydroponic cannabis growers.
Auto Ultimate, exceptional yields of very high THC cannabis
Auto Ultimate is simply one of the best yielding autoflower seeds ever released by Dutch Passion. She does well under 20 hours of daily light from autoflower seed to harvest. This indoor grow timing schedule also works well for the entire range of Dutch Passion autoflower strains.
Unlike other autos, Auto Ultimate has a slightly longer growth cycle of around 12-15 weeks. Whilst this may be a month or so longer than other autoflowers, the extra time is required for Auto Ultimate to complete production of her extravagant XXL yields. The crystal covered buds grind up into a deliciously scented oily slurry which burns with an audible sizzle. These are high quality buds with powerful stress-dissolving effects which bring a smile to your soul.
The longer cycle time, in combination with the one-of-a-kind XXL genetics, are highly recommended to any hydroponic cannabis grower. Crazy yields don’t infer quality compromises either. THC levels are officially rated as very high (around and perhaps just over 20% THC) and will satisfy the most demanding users.
Auto Ultimate is part of the Classic Cannabis seed family. These strains are established and fully proven customer favourites with several cannabis cup winners amongst the ranks. Auto Ultimate’s photoperiod feminised seed sister is called The Ultimate and also has the same outrageous yields.