We know D.C. Get our free newsletter to stay in the know. If you love City Paper , get it every day in our newsletter. Hopefully all of you aspiring growers have been able to get your seeds Many cannabis consumers have found an occasional seed in their bag of marijuana. But can you actually use them to grow your own weed? Learn more about germinating bag seeds and turning them into flourishing cannabis plants. Seed Starting, Part 2: What To Do After Germination Check out our latest tutorial video below about what to do with your seeds after they have started to germinate (when they’ve started to grow).
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Hopefully all of you aspiring growers have been able to get your seeds so we can move to the next step: germination.
Take great care handling seed and seedling. Most flower and vegetable seeds are simply planted directly in the soil, but because of the value of cannabis seeds, germinating seeds prior to planting is encouraged. Growers can achieve a much higher survival rate by germinating in a non-soil medium and then transferring the seed to soil once the tap root has emerged from the seed.
Here is one of the simplest and most successful methods: Put a double layer of paper towels on a dinner plate, then thoroughly soak the towels with water and tilt the plate to drain off the excess. Place your seeds on top of the wet towels and cover with another double layer of soaked paper towels. Be sure excess water is drained off—you don’t want the seeds to be swimming.
Cover the plate with an upside-down plate or pot lid. A plastic bag or plastic wrap also works. Don’t make the seal tight—you want to leave some openings to allow air flow.
Keep the germinating seeds away from direct light. For best results, keep them at about 75 degrees Fahrenheit. A radiant heat source, like a heating pad, helps expedite the process. If you’re using a heating pad, be sure to keep the heat setting on low and place a folded hand towel between the heating pad and plate: Direct contact between the plate and heat source can cook your seeds.
Under the right conditions, seeds usually open in one to five days, so check them daily. Do not allow the towels to dry, and add water as needed to maintain moisture. Some seeds can take as long as 10 days to germinate, but if seeds have not opened within 10 days, they are not viable.
When the seeds open, the first thing to emerge is the root. Once the root sprouts it can grow quite fast.
When the root grows to a few millimeters in length, the seed is ready to be transferred to soil. Always take great care not to damage the tap root when handling. The best soil to use for a sprouting baby ganja plant is a “seed starter” or “seedling” mix. These are light neutral blends with very little fertilizer. Heavily fertilized soils will kill seedlings quickly, and cannabis seedlings prefer loose, aerated soil that their roots can easily penetrate. A bag of good starter soil is easily identifiable: When you pick it up, it should feel light and fluffy. Soils that are heavy and compact are not good for seedlings.
Now, on to potting (no pun intended). A healthy seedling will be ready for transplanting into larger container, with richer soil, in about a month. A 16- to 20-ounce container is ideal for a seedling’s first home (many growers use a Solo cup). The container must drain, so punch some holes if needed.
Fill your container with pre-moistened soil and create a hole about a half-inch deep for your seed. The tip of a pencil works well for making the right sized hole. The seed should be about a quarter-inch below the surface.
Place your germinated seed, root down, into the hole and cover lightly. Do not pack the soil on top of the seed; a light protective layer of soil is all that is needed.
Once they sprout in one to three days, new seedlings will need lots of light, and fluorescent grow light works best. Give your baby ganja plants 16 hours of light per day.
It’s very important to have a breeze on your plants immediately. A fan placed at the proper distance and speed should create a breeze just strong enough so your plant “dances,” but not so strong that it’s bent in one direction.
Without a breeze, indoor ganja plants won’t receive the stimulus needed to develop sturdy stems and branches, which the plant will need to bear the weight of big, sugary buds.
The Potanist is written by Bud Baker and Herb Green (yes, those are pseudonyms; yes, they are real people). Reach them at [email protected]
Graphics by Stephanie Rudig
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How to Germinate a Bag Seed
F inding a seed in your bag of weed used to be regarded as an insult, an indication you scored some inferior product. But it’s a new millennium, and growing cannabis is perfectly legal in some states and territories. While buying seeds online is still recommended for reasons we will detail further, finding a healthy seed can be as valuable as an ounce of gold. Or at least the cost of the bag.
- Can You Tell if a Cannabis Seed is Male or Female?
- How to Store Marijuana Seeds Properly
- Feminized Cannabis Seeds Explained
- How to Start Seeds
In this article we review the steps to germinate cannabis seeds, tips and tricks in the process, and how to keep your seedling healthy.
Germinating a seed is the first step in the growing process, and a cannabis seed will sprout with a voracious hunger, so if you are about to germinate seeds, start thinking ahead about where the seedling will eventually be moved to. This includes lighting, ventilation, and something to feed the lady. Those things don’t need to be decided before you begin, but try to have a plan in place by the time the second set of leaves emerges — as soon as two weeks.
The Germination Process
Begin by soaking the seed overnight. Soaking the seed saturates it with moisture, and moving it shortly after to a warm home tells the seed that it’s someplace comfortable, and it’s time to grow. Tap water is fine for this, but a micronutrient solution like liquid seaweed may be included.
Once your seed has soaked, the most common method for germination is the “paper towel method.” Wet a piece of paper towel and wring dry, then fold in half. Place the seeds between the halves of the damp paper towel, and slide the whole thing into a ziplock bag. Seal with some air inside. Leave this bag someplace comfortably warm for about a week, checking frequently for spots of mold. After about a week, a taproot should emerge.
Then it is time to transfer the seed into a proper growing medium. Be careful plucking your seed from the paper towel!
A grow medium is the “stuff” the seed will sit in. The easiest option is soil, healthy black earthy scooped up from your yard, or potting soil purchased from any garden center. Rock wool cubes are a common option for hydroponic growers, but can later be transplanted into soil as well. Compost and worm castings are great for a seedling, but it will need to be transplanted into a more diverse mixture later.
It is far too early to begin any nutrient cycle, or to introduce any fertilizers to the soil. Now that the seed is confirmed as alive, and placed into a more comfortable medium, simply make sure that the seed is watered and warm.
The first set of leaves to emerge are called “sucker leaves,” and their sole purpose is to drink in as much light as possible to fuel the growth of the more recognizable serrated leaves, which will begin to grow over the next week. After that you’ve got a proper seedling, and in a few weeks it will be ready for a bigger home!
For further guidance and resources about growing cannabis, see our Beginner’s Guide to Growing Marijuana, or our guide to growing for personal use.
Cultivating a Healthy Cannabis Seedling
The seedling that emerges will be as tender as an infant, and susceptible to diseases and cross-contaminations, so keep your germination station as sanitary as possible, and wash your hands before handling them. Avoid rubber or latex gloves at this stage as they have too much grip, and one wrong movement of your finger could accidentally grab and tear the soft plant material.
A seed’s health may be fortified by soaking it with a solution rich in micronutrients, like liquid seaweed. Be advised, however, that these will be very diluted solutions. Carefully read the mixing instructions of any product you purchase.
Seedlings can be protected against certain diseases by including worm castings in the medium. Research out of Cornell University has shown the microbial life in worm castings colonizes the seed’s surface, making it more difficult for pathogenic microbes to establish themselves.
Disclaimers and Downsides Regarding Found Seeds
It’s worth pausing to remember that seeds shouldn’t wind up in your bag of cured, smokable cannabis. So before planting anything, let’s assess what this seed is, and how it got there.
Only female cannabis plants produce flowers, and if they are pollinated by male plants, then they produce seeds instead. So all the cannabis we smoke is from unpollinated female plants — or nearly all of it.
When female plants are stressed — for instance, by drought conditions or nutrient problems — an evolutionary alarm can induce them to produce seeds with only their DNA. The problem with these “hermaphrodite seeds” is that the offspring, having benefited from this process, will be more prone to repeat it. If this is how a seed got in your bag, it can result in seedy weed, even under the closest care.
A seed is not guaranteed to sprout at all. Examine the seed for any obvious health issues. Immature seeds are lighter greys-to-green, while mature seeds are darker tan, brown, or even black. A healthy shape is a teardrop or nearly round, while bunk seeds will appear shrivelled or irregular. Finally, healthy seeds have a hard, whole shell, while cracked or brittle shells will likely not sprout, or produce a less healthy seedling.
A found seed is also not a guarantee to produce a replica of the strain you smoked, and may present latent traits from the strains it was bred from. Cultivating a complete copy of a phenotype is called “cloning,” and the cloning process must begin with a living plant, not a seed.
Remember, it could also just result in a male plant, which won’t grow any buds. None of this is guaranteed to happen with a bag seed, it’s just more likely than with a stabilized seed from a producer.
If you want to germinate a seed you’ve found, begin by soaking it overnight in water to saturate it, and soften the shell. Micronutrient solutions can be mixed in at this stage to fortify the health of the seedling (if you do, be sure to read the mixing instructions on the label).
The “paper towel method” is the most accessible way of germinating almost any seed. Once a taproot has emerged (after about a week) plant the seed into a small container with your chosen grow medium, like soil. Do not fertilize at this stage, as the seed and resulting seedling are very tender, and concentrated fertilizers are abrasive chemicals. Within another week, “sucker leaves” will sprout, synthesizing light to produce further growth.
Remember, found seeds are not always healthy or even viable. A healthy seed has a hard, unbroken shell and a dark color, while brittle or misshapen seeds may not produce a healthy plant, if anything at all. A found seed is also not guaranteed to replicate the precise phenotype of that cannabis you found it in.
That said, it’s almost always worth trying, and experimenting with whatever results. Growing cannabis can be an enriching experience, and perhaps even save you some riches. As long as you know what to look for from a seed, and how to handle them, finding one in your bag could be a golden ticket.
Seed Starting, Part 2: What To Do After Germination
Check out our latest tutorial video below about what to do with your seeds after they have started to germinate (when they’ve started to grow). Then keep scrolling for some tips and links to help you out! If you missed the first video on How to Successfully Start Seeds, be sure to check that out first, as it will get you started on growing a great garden – whatever your skill level.
>> Download: When to Start Seeds Indoors
We also have for you an easy-to-follow written guide on when to start what.
Your seedlings will need light, but they also need periods of rest (darkness) too. A good rule of thumb is to turn the grow lamps off when you go to sleep, and turn them on when you wake up (or use a timer). Read all about different types of grow lights here.
Seedlings need blue night and red light. Sunlight includes both. Red light stimulates the growth of leaves and flowers. Blue light regulates the growth/size of plants.
Don’t use incandescent light, use fluorescent. Full spectrum bulbs include both red and the blue light, or you could use one warm (red) light and one cool (blue) light.
The grow lamp should be about 2-4 inches above the seedlings, so adjustable lights are helpful. You can find the Tabletop Garden Starter® Grow Light Kit shown in the video (and in the photo above) from Gardener’s Supply.
Be sure you clean the lightbulbs, as dust and dirt can cut down on the amount of light emitted.
Hold your hand above the seedlings. If it feels warm, the light is too close.
Water from below, not above, to ensure that you don’t squash the seedlings. Make sure your seedlings aren’t sitting in water, or you’ll have issues with rotting, fungus, and soil gnats.
Your seedlings might need to be watered if:
- The soil looks lighter
- The soil pulls away from the edge of the cell
Self-watering seed starting kits use capillary mats, but be sure to check the water levels on those as well.
Seedlings need food when they get their “true leaves.” The first leaves that come up are typically embryonic leaves from the cotyledon (part of the seed) so look for the second (“true”) leaves to appear before you start fertilizing. Use fertilizer at a weaker strength than you would for full-sized plants.
There are several different options for how to fertilize your seedlings. The ones shown in the video are Sustane Compost Tea Bags and Alaska Fish Fertilizer 5-1-1 Concentrate 1 Quart
Your seedlings will be healthier and more sturdy if air is flowing above and around them. A fan can be used – we recommend putting it on a timer, just like your grow lights.
5. Room to Grow
Most people put more seeds than are needed in each cell, so you’ll need to either (carefully) pull out the weaker ones from each cell, leaving one healthy one, or cut them off at the base. Monica demonstrates both methods in the video.
Be sure to check your seed packet to see how long it should take your seeds to germinate. If no seedling has appeared by a few days later than expected, sow some new seeds.
6. A Bigger Pot (optional)
It’s not needed, but if you’re not moving your seedlings into a garden for several weeks, you might want to transfer them to a larger container. If your plant is about two times the size of the container it’s in, or you can start to see roots below the cell, you might want to move it to give it more room to develop, access to more nutrients and more moisture, and the roots will have more space to grow. A 3 to 4″ pot should work well.
If you’re reusing pots, be sure you wash them well before you use them.
You can also use Eco-friendly Seed-starter Cowpots, which you eventually plant into the ground, adding nutrients and organic matter to the soil.
Use a potting mix (such as the Organic Potting Mix, 20 Qts. from Gardener’s Supply) when you transplant your seedlings. Make sure that it is adequately moist – if you grab a handful and squeeze it, it should hold together, but if you move your hand, it should fall apart (see the video at about the 23 minute mark for a demonstration of this).
When transplanting, never grab a seedling by the stem, or you could damage or kill the plant. It’s better to try to push it up from the bottom of the cell, and try to take it out in one piece.
After transplanting, be sure to still water your seedling from below.
Important note: when you do move your seedlings outside, you need to do something called “hardening off,” which is slowly exposing them to the conditions they will encounter in your garden.
Be sure to label your seedlings so you know what they are!
Ones shown in the video include ones similar to these seed markers. The garden stakes from Botanical Interests are currently sold out. One of our YouTube viewers also suggested using venetian blinds as labels. We thought that was a great idea!
What are you growing from seed this spring? Let us know in the comments below! And don’t forget to subscribe to our YouTube Channel.
Disclaimer – All opinions expressed here are those of the author based on personal experience using the product.
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About The Author
Sarah, originally from Wisconsin, prefers to be outdoors whenever possible. She has been known to high-five trees on hikes, tests the limits of her balance on kayaks, and is re-discovering a love of cycling. She works behind-the-scenes at the Gardening Products Review, located in sunny Tucson, Arizona.