How To Grow A Weed Seed Without Soil

Whether you call it weed, cannabis, pot, marijuana, or something else, the plant known as Cannabis sativa is actually easy to grow at home when you know what you need to do. Growing hydroponically will provide you with higher yields and a… This marijuana germination tutorial is different. Get exact steps from beginning to end (with pictures!) so your germination goes fast and seedlings start strong! You grow plants in soil, right? Not with hydroponics! Read here whether growing cannabis on water can also be a solution for you.

How to Grow Marijuana Hydroponically

This article was co-authored by Lauren Kurtz. Lauren Kurtz is a Naturalist and Horticultural Specialist. Lauren has worked for Aurora, Colorado managing the Water-Wise Garden at Aurora Municipal Center for the Water Conservation Department. She earned a BA in Environmental and Sustainability Studies from Western Michigan University in 2014.

There are 14 references cited in this article, which can be found at the bottom of the page.

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Whether you call it weed, cannabis, pot, marijuana, or something else, the plant known as Cannabis sativa is actually easy to grow at home when you know what you need to do. Growing hydroponically will provide you with higher yields and a shorter grow time compared to growing in soil, but it can often be difficult for the beginning grower to get started with hydroponics. However, most people think of plants growing in water when they think “hydroponics” but actually your plants will get many of the benefits of hydroponics as long as they’re getting their nutrients directly in their water supply. However because of superior air to water ratio in hydroponics, it remains the industry standard. This tutorial will show you step-by-step how to grow your marijuana in 3-4 months using the (arguably) easiest hydroponic method: hand-watering in a soil-less medium.

Fail-Proof Cannabis Germination Method in Soil or Coco

We have a cannabis seedling germination page that includes everything you need to know about all the different germination methods, but this tutorial is different. In this tutorial, I’m going to share exactly how I do my seeds from beginning to end. Just follow these instructions and you’ll end up with healthy, fast-growing plants that germinate in just a few days. It’s basically fail-proof.

Turn your cannabis seeds…

This step-by-step tutorial will teach you how to germinate seeds and provide basic seedling care

Soon you’ll have healthy cannabis plants to admire

Supplies Needed

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.) Prepare Your Soil or Coco Containers

Before you start germinating your seeds, set up your soil or coco. It will still be a few days until your seedlings arrive, but you want to have everything ready before the seedlings need to be planted.

Get your containers ready before you start germinating

3.) Germination

When it comes to new growers, it seems like the most fool-proof method (at least for me, and many of the new growers who write in) is the Paper Towel Method! It’s so simple, but there’s something about wet paper towels that a young seedling loves Learn About Other Ways to Germinate Seeds.

Paper Towel Method – Place your seeds inside a folded wet paper towel (Important: use cheap brand!)

This method is hard to mess up if you follow the instructions. Place your seeds inside a folded wet paper towel, and put that between two plates. The purpose of the plates is to prevent the seeds from drying out. Don’t let any part of a paper towel hang out the edges or it will wick away all the moisture and dry out. Keep everything totally contained between the plates.

Surprisingly, the really cheap paper towels work the best because the seeds and roots lay on top without getting stuck to anything. This is important. The more expensive “cloth-like” paper towels (like Viva brand) aren’t good for germination because the roots actually grow into them instead of laying on top.

Wet a paper towel (use the cheapest brand you can find). If growing multiple strains, you may want to label the paper towel so you know which is which. Place each seed on the wet paper towel next to their label.

Cover with another wet paper towel

Add another plate on top to keep the paper towels from drying out. Make sure now paper towel is sticking out the sides.

Tips

  1. Check on your seeds every 24 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.
  2. They should germinate in 1-4 days, though some seeds can take 7 days or longer (especially older and smaller seeds).
  3. Keep them warm if possible. Seeds 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. I leave mine near a sunny window. I usually put a thermometer in the same place to make sure it’s not too hot or cold (or just check the plate with your hands)

Here are those seedlings about 2 days later. Be extra careful when removing the paper towels. Don’t let the seeds roll around or you won’t know which is which. This is when you’ll be glad you used cheap paper towels, as they are much easier to peel off without disturbing your seedlings.

You can see some of the seeds sprouted, but some of them haven’t yet. That’s totally normal! Each seed is different. If this happens to you, you have two choices. You could plant the ones that have already sprouted and let the other ones stay in the paper towels until they germinate. Or you could just put all the seeds in Rapid Rooters now, and hope for the best as far as the slow-sprouting ones. It’s up to you. Letting the unsprouted seeds stay in the paper towels longer improves the germination rate in my experience, but it’s simpler (easier) to move them all at once.

Seeds often germinate at different rates even if they get the exact same conditions

4.) Place Germinated Seed in a Rapid Rooter

Now it’s time to get your Rapid Rooters! Alternatively, you could place your sprouted seeds directly in the final growing medium (coco or soil). I think these help them get started, but I’ve grown many successful plants by just putting the germinated seed directly in its final home.

See also  Winter Weed Seeds

Rapid Rooters are nice, but not necessary

The Rapid Rooter should be cut open lengthwise. I use big scissors but you could also use a knife.

Gently place the germinated seed inside, root down. Place the seed close to the surface so it doesn’t have far to go.

If you have a root that is curved or bent, don’t try to straighten it out. Open the Rapid Rooter and lay the germinated seed down gently. It will naturally lay on its flattest side. When you slowly close the Rapid Rooter, the bent parts of the root will end up in the “crack” of the Rapid Rooter that you cut to split it open from the side.

Most seedling plugs will go back into place easily, and you’ll barely be able to tell it’s been opened. I love Rapid Rooters because their texture causes most seeds to stay in place and not “fall down” further into the hole once you’ve got the Rapid Rooter closed.

5.) Water the seedling in the Rapid Rooter until you see a root come out bottom, 1-2 days.

Make sure to always keep the Rapid Rooter moist but not soaking wet and give plain water.

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 often you actually see the seedling push the shell above ground.

Don’t touch the shell if possible because a tiny tug in the wrong direction can pull the seedling out of the plug and break off the taproot.

Try to let the seedlings break free if possible. But if you have a seedling that’s stuck in a shell after a day or two, and doesn’t seem to be getting any better, you need to go in and help.

I’ve found that pointy tweezers are perfect to pry open a shell that’s stuck. Just close the tweezer, stick it inside between the shell halves, and let it slowly open to pull the shell apart without you ever touching the seedling.

Sometimes a “film” from inside the shell gets stuck on the leaves. If that happens, try putting a drop of water on the film a few times a day to soften it. If the seedling doesn’t push it off on its own, hold the stem between your fingers (so it doesn’t pull at the root) and use tweezers to gently tug at the membrane and release the leaves.

Don’t use a 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 as high humidity as clones (which are what the domes are designed for), and seedlings tend to get “wet feet” and stop growing as fast in constantly wet conditions.

Water your seeding in the Rapid Rooters until you see a root coming out the bottom. Keep Rapid Rooters moist but not wet. During this time, give seedlings bright filtered light. A CFL or LED light bulb kept several inches away works well. I’ve left mine on the kitchen table next to a sunny window, and that’s also worked fine for me as long as it doesn’t get too hot.

You should see a root come out the bottom in just a day or two!

After you see your first root, it’s time to…

6.) Put Seedling in its New Home

You are about to water your seedlings for the first time, so prepare your water now.

  • Coco – Prepare water with seedling-strength nutrients, and make sure to pH your water to 5.5-6.5 right before giving it to plants. Unlike soil, coco does not naturally contain any nutrients so you must provide nutrients in the water from the first watering.
  • Soil – Prepare plain water at 6-7 pH. You don’t need to add nutrients for the first 3 weeks or so because your plants will live off what’s in the soil. Adding extra nutrients at this point might overload and burn the seedlings.

Now that your water is ready, dig a hole that’s a little smaller than the Rapid Rooter, and place your seedling plug inside. The idea is to let the Rapid Rooter stick up above the soil a little to help the roots get more oxygen. It’s okay if the plug goes in flat with the soil, but don’t bury the stem as that can cause stem rot in some cases. Even if you’ve got a tall seedling, you usually won’t notice the extra length once the plant is bigger.

Gently pack the nearby soil/coco to hold the Rapid Rooter in place so the seedling is stable.

Your seedlings get a little extra oxygen if you let the Rapid Rooter stick up into the air slightly as opposed to burying it.

Example of cannabis seedlings growing in coco coir, about to get seedling-strength nutrient water. If they were in soil, I would give plain water for the first few weeks.

Water immediately in a small circle around your seedling. For most grow mediums and containers above 1 gallon, you can give 2 cups (500 ml) of water immediately without overloading your seedling. If the grow medium feels moist (for example coco that was recently re-hydrated), give 1 cup (250ml) of water this first watering.

Give 2 cups (500 ml) water in a circle around the seedling. If the grow medium is already wet, give just 1 cup (250 ml)

How to Water Seedlings in the Beginning

Two Main Goals

  • Seedling roots never dry out (most important)
  • Seedling roots aren’t staying soaking wet (roots need oxygen)

Seedlings “drown” and die due to lack of oxygen if they get too much water too often. To avoid this, try to provide an amount of water that lets you water seedlings every few days. Avoid giving so much water that the seedling roots are in a super wet grow medium for days as this causes “damping off” and root problems. Some grow styles like high-frequency fertigation call for watering more frequently. Just remember that the more often you water your plants, the less water you should give at a time. Also, keep in mind that a smaller container tends to dry out fast while a bigger container holds onto the water for longer

Try to maintain a schedule that lets you water your plants every few days without them looking droopy

  • Water in a small circle around the base of the plant at first
  • If the growing medium feels dry within 1 day, give more water next time. Otherwise, give the same amount again next time you water
  • Repeat, until you can give enough water to get at least a little runoff, and have it dry in a few days
See also  Weed With Long Seed Pods

If the medium is drying in less than 2 days, it means you need to give more water to the plant at a time, or possibly transplant to a bigger container if the plant has outgrown its current one.

If your growing medium takes longer than 3 days for the top inch to dry, it means the soil is staying wet too long, and plant roots aren’t getting enough oxygen. It also puts your plants at risk of getting fungus gnats . Try giving less water at a time until the plant is drinking more. It’s possible you may have a problem with drainage in your medium ( what is good soil? ) or there are no drainage holes so extra water can’t come out the bottom of the container. Always remove any runoff water instead of letting the plant sit in it.

More seedling resources

Some growers like to put seedlings in solo cups and then into their final container. When done right this can increase the rate of growth by providing more oxygen to the plant’s roots. If you go that route, I recommend paper cups as they’re not as bad for the environment.

Autopsy: Why Aren’t My Marijuana 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 be soaking 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. Even if you purchase from a good breeder, sometimes you still get duds. How can I tell if seeds are viable?

If seeds sprout, but then stop growing…

  • Temperature is too hot or cold – aim for 75-80°F
  • Too wet – new seedlings don’t like “wet feet” so make sure your Rapid Rooter or growing medium never looks shiny or muddy, as that means there’s too much water! 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 drier 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 than 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. But if you follow this tutorial you will get the best results possible.

Hydroponics: Growing Cannabis Without Soil

If you’re thinking about growing cannabis plants, chances are you’ll think about pots filled with soil. However, in hydroponics, weed is grown in water instead of soil. This technique is also known as hydroculture or RDWC (Recirculating Deep Water Culture), but hydroponics is the most usual term. This method is not as complicated as many people think. Actually, growing gets easier with this technique, as plants will grow faster because they can absorb more nutrients. Hydroponics is suited for just about any plant, but it works especially well with vegetables and cannabis. This blog tells you just what hydroponics can do for you as a cannabis grower.

How Does Hydroponics Work For Cannabis Growers?

To be fair, hydroponics sounds like a pretty impressive technique. The word itself comes from the Greek concepts of ‘hydros’ and ‘ponos’ (‘water-work’; the ancient Greeks worshiped Hydros as an old god of water, and Ponos as the god of hard work). Ironically though, hydroponics done right isn’t hard work at all. Of course, it’s a matter of preference in the end, but most growers agree that hydro grows are easy once you get you get the hang of it.

Hydroponics is on the rise; mostly because it gives growers greater control over how their plants develop. Instead of growing your weed plants in soil, you grow them directly in water containing all necessary nutrients. That comes with some distinct advantages, making this technique an interesting option for advanced and amateur growers alike.

Liquid Lunch: Nutrients Straight From The Water

In hydroponics, plant roots are suspended straight in the water rather than in soil. That makes water the substrate or grow medium. Substrate is just a fancy term for ‘bottom layer’ (‘sub’ + ‘stratum’). Such layers can be anything from sand or rockwool to coco fibre, gravel, or clay pellets. In cannabis hydroponics, water is the grow medium; even if there’s a layer of clay pellets in the top section of a (floating) pot for stability. Nutrients are dissolved into the water and delivered straight to the roots. Any water that is not absorbed is recycled by the system for future use. Roots of plants grown in hydroponics tend to be longer and paler than their soil-grown counterparts, with fewer side branches. This is caused by the low oxygen content of water compared to soil.

Basically, any plant can be grown using hydroponics. Cannabis thrives on it, but these days, you’ll find entire farms growing lettuce and leeks on water alone. Fun fact: the increasing popularity of growing cannabis at home has been one of the driving forces behind the development of new hydroponics systems used in regular agriculture!

Cannabis Hydroponics Basics

The diagram below shows the basic components of a simple hydroponics setup for cannabis growers.

1: Substrate; in this case, water containing nutrients. Some systems have plants suspended directly in water, while other favour pots with a top layer of clay pellets for extra support;

2: Cover preventing evaporation and contamination of the substrate. This is usually a floating lid with holes providing a snug fit for suspended plants;

3: Aeration or oxygenation; usually in the from of an exhaust unit blowing air bubbles into the water;

See also  How Much Light Does A Weed Seed Need

4: Air pump. Many hydro setups feature a separate water pump with a filter to keep the water clean while circulating.

Different Cannabis Hydroponics Systems

The one thing all hydroponics systems have in common is the lack of soil needed to grow your cannabis plants. Hydroponics gets your cannabis plants everything they need, except light: nutrients, oxygen, and water. This can be done in several ways. Below, you’ll find a summary of the most common hydroponics systems.

(R)DWC: (Recirculating) Deep Water Culture.

(R)DWC: (Recirculating) Deep Water Culture

RDWC is the easiest system to manage, making it a great option for beginners. You put your germinated plants into individual containers, which you then place into a water container. All you add is some hydro pellets to give the roots some added grip. An air pump ensures a constant air supply into the water. Nutrients are added to the water, which the plants can then absorb through their roots. That means roots are constantly exposed to water throughout the growth cycle. The R in RDWC stands for Recirculating, because the water is constantly pumped around the system in a closed loop.

RDWC System without plants.

NFT System

This is a slightly more complex system to use. NFT stands for Nutrient Film Technique. Here, plants grow with their roots in a wide tube, usually made of PVC. The oxygen-rich water carrying nutrients is pumped from the reservoir to the tubes and back. Tubes should be installed at an angle to ensure ample water flow back into the reservoir. The ‘Film’ in NFT represents the ideal situation in which just a thin filmy layer of water and nutrients flows over and along the roots.

This system is great at providing nutrients to your plants. If set up efficiently, it also saves water and power. One potential problem is clogged tubing due to roots blocking the flow. That gives bacteria a chance to grow, which of course will negatively impact your plants. Stay sharp while trying NFT!

Ebb And Flow System

In an ebb and flow setup, the roots are not constantly submerged. A pump regularly fills the container with oxygenated and nutrient-rich water. When the container is full, the pump stops working, allowing the water to flow back into the reservoir. It’s a bit like running your own little mangrove at home. You set the ebb and flow intervals according to what your plants need.

How about running your personal mangrove at home?

Drip System

Drip irrigation is a popular technique among professional growers all across the agri- and horticulture sectors, but amateur homegrowers will find it very convenient, too. You feed and water your plants using a drip system. Every individual plant gets its own drip nozzle. That allows for very accurate distribution of nutrients, ensuring that every plant gets an equal share. Any liquid not absorbed by the plants flows back into the reservoir for future use.

The Benefits Of Cannabis Hydroponics

Compared to growing in soil, hydroponics can have many benefits.

  • You can target your nutrition more accurately, because you don’t depend on what happens to be present in the soil. That allows you to set the perfect nutrient mix without losing valuable ingredients along the way;
  • Save yourself work: no need to remove weeds, while the system makes sure your plants are fed and watered. Just keep an eye on the water level in your reservoir. Two refill a week will usually do the job. As you can see, hydroponics is perfect for lazy relaxed growers;
  • Your plants will absorb the exact amounts of water and nutrients they need; no more and no less. The system simply recycles any excess water, making it a very efficient system too. Obviously, as a plant enthusiast, you care about the environment: life’s good when you can save the world by growing sustainable weed;
  • Pest control: hydroponics environments are cleaner than regular soil. That limits the options for pests and bugs – one thing less to worry about;
  • Better yields: plants grow better in hydroponics. For cannabis, that means better yields than for weed grown in soil, all other factors being equal;
  • Rapid growth: using a hydroponics setup could reduce the growth phase of your plants by three weeks. Roughly speaking, that could mean two extra harvests every year;
  • Not dependent on the weather: hot, dry summer? Freezing cold winter? It’s all the same for hydroponics, because all the plants get exactly what they need, no matter the weather. You don’t even have to keep track of the seasons – if you’re growing indoors, that is.

Drawbacks Of Hydroponics

Using hydroponics for cannabis does come with a few minor drawbacks, though. Firstly, you’ll need to spend more on equipment before you can get your system up and running. Then again, working with the right system eventually pays off in terms of saving on water and electricity.

The second and most important drawback is the tight margin for error that hydro grows offer. Soil has considerable buffer capacity: any surplus of nutrients or lack of oxygen can be compensated in part by the soil and the micro-organisms it contains. Hydroponics barely has any buffer capacity in this sense. Overdosing on nutrients or – worse – power outages will almost certainly damage your plants. That means hydroponics calls for some more vigilance from you as a grower. As long as you know what you’re getting into, though, that should not be a problem.

Outdoor Cannabis Grows Using Hydroponics

Most growers using hydroponics for their cannabis choose to do so indoors. That makes sense from the perspective of optimal control over equipment, lighting, and a bunch of other factors. Such control is slightly trickier to achieve with outdoor grows, but theoretically, hydroponics works perfectly well out in the sunshine. In fact, there are serious plans for using hydroponics as a technique for tackling global hunger issues. Of course, outdoor hydroponics calls for some extra attention to typical open-air factors like the weather, disease, and fungi, but it is certainly an option. A little greenhouse can be a big help, but you don’t strictly need one. What’s more, technology keeps improving all the time, so who knows? You could be running your own water theme park in your back garden come next grow season. At any rate, though, it’s good to know we’ll solve the world’s food problems by the efforts of weed growers such as yourself!

Getting To Grips With Hydroponics

As you’ve seen, cannabis hydroponics opens the door to carefree growing and enjoying better harvests from your weed plants. So, do you feel like starting up your own hydro grow? Give yourself the best possible start with our world-famous cannabis seeds!