How to Grow Marijuana from Seed
If you’re in a location where cannabis (another term for marijuana; short for the plant cannabis sativa) is illegal, growing it is probably illegal too. Bringing in seeds or cuttings to your location can very well be a felony, and reputable sellers won’t ship to you.
You can probably purchase and grow hemp seeds and plants, which have a negligible amount of THC, but these plants won’t produce the psychoactive effects of plants that contain higher levels of THC. Check with your seller to be certain you’re getting what you think you’re purchasing. If you buy seeds for CBD-only hemp plants by mistake, you can end up being very disappointed post-harvest.
How to acquire seeds or cuttings
You can usually find cannabis seeds for sale at most dispensaries in areas where growing cannabis for personal use is legal. You may also find growers who sell cuttings/clones. You can expect to pay $50 to $100 for a pack of ten seeds. When shopping for seeds or cuttings, read the labels and any other information the manufacturer provides on its website or in its catalog to make sure you’re getting the right seeds or cuttings (the strain) for the plants you want to grow.
One way to get your mitts on some seeds is to collect seeds when you find them in flowers you purchased, or get some from friends if they’re collecting.
- Feminized seeds: Nearly all seeds sold by reputable companies are feminized, but make sure they are. These seeds are specially treated to grow into female plants.
- Auto-flowering or photoperiod: Auto-flowering plants are easier, because they enter the flower stage after a certain number of weeks regardless of the light/dark cycle. If you’re a beginner, seriously consider going with auto-flowering plants.
- Genetic background: If seeds are from a well-established strain, such as O.G. Kush, Bubble Gum, or a cross-breed, the genetic background should be stated.
- Blend: The blend represents the percentage of the three species — sativa, indica, and ruderalis. All auto-flower strains contain some percentage of ruderalis, which is responsible for the auto-flowering nature of the plant.
- Yield indoors: The number of grams of bud per square meter of plant when grown indoors.
- Yield outdoors: The number of grams of bud per plant (after drying) when grown outdoors.
- Plant height indoors: Shorter than when grown outdoors.
- Plant height outdoors: Taller than when grown indoors.
- Time to harvest: Approximate number of weeks after germination the flower should be ready to harvest.
- Potency: Percentages of CBD and THC.
- Effect: The type of experience you can expect when consuming product from the plant.
Know the laws about buying cannabis
- In some European countries, laws prohibit growing cannabis, but seed is legal, which is quite confusing. You’re allowed to buy and eat cannabis seeds because they’re non-psychotropic, but you can’t buy them to grow cannabis. Other countries in Europe, such as Germany, have their own seed laws.
- In Canada, where cannabis is federally legal, seeds can be shipped across provincial lines.
- In the U.S., in some states in which cannabis is legal, you can purchase seeds from some dispensaries or other locations to grow plants as long as you keep them in the state. Other states may bar selling to non-licensed growers. Shipping or transporting seeds across state or international borders is illegal, although a few reputable online seed stores ship to individuals with success.
Cuttings are typically treated in a similar manner as seeds in legalized locations. They may be available from some dispensaries or outlets for pick up or delivery with a fee. They’re prohibited from crossing U.S. state lines or international borders. You can buy individual plants and mix and match strains. Prices vary and are often determined by plant size.
Buy cuttings (clones) only from a reputable source who understands proper back-crossing of strains for stability. Back-crossing involves pollinating a plant with one of its parent plants to promote sexual stability, so that when you have a female it won’t hermaphrodite into a male during flowering.
Both seeds and clones are often able to be purchased from commercial locations already in your state.
In the U.S., transporting any part of the cannabis plant over state lines is illegal. This applies to seeds and clones and, technically, even to tissue samples.
How to germinate cannabis seeds
Germinating seeds requires a dark environment that is around 70 degrees. There are many ways to germinate seeds (in soil, in a wet paper towel, in starter plugs) You can also sow them directly into soil in a garden or container, as long as the soil is light and fluffy, so the roots can easily grow down and the stalk can break through the soil. Plant the seeds about 1/4- to 1/2-inch deep and cover them loosely with soil.
Most importantly, seeds need a moist environment; they won’t germinate if they get too dry. You can use a heat mat to increase the success of germination in colder climates.
How to transplant marijuana plants
When transplanting any plant, whether it started from seed or a clone, handle it gently, being very careful not to damage the roots. Center the plant in the pot, and plant it deep enough to cover the root ball completely in soil. If the plant is root bound, you can gently tease the roots apart to encourage outward growth.
Pack your soil or other grow medium down around the roots well enough to support the plant while new roots grow, but not so tight that the soil restricts outward root growth. Water the soil around the roots.
About This Article
This article is from the book:
About the book authors:
Kim Ronkin Casey has been a communications professional for more than 20 years and recently took a year-long leap into the world of cannabis as the communications manager for one of the leading dispensaries in North America. She now consults for companies in the industry on internal and external communications. Joe Kraynak is a professional writer who has contributed to numerous For Dummies books.
How Can a First-Time Grower Have a Successful Seed-to-Harvest Grow?
“Growing our plants has some things in common with flying an airplane. I can go over every fine detail of how to fly the plane. I can tell you exactly what to do when this happens and that happens. I can educate you on every detail of becoming a pilot. That does not mean that you can now fly the plane without crashing. You need experience before you will have a smooth flight form takeoff to landing.That being said, what does a first time grower need, in order to have the best chance for a seed to harvest successful grow?”
The most important elements of a successful grow are…
- Strong, direct light (whether it’s from the sun or a grow light) – this directly powers the growth of buds. With weak light you’ll have small yields and airy buds that lack potency
- Good root environment (air and water) – At it’s most basic, the roots need constant access to both air and water for the best results. There’s different ways to provide this environment. You can even grow with your roots hanging in the air with water being misted on them! (here’s a picture). You can use soil or coco coir, or even grow your roots directly in water (with bubbles being made in the water to provide a source of oxygen). When it comes to picking a grow medium for cannabis, if you want the fastest growth you want to choose something that maximizes the water and air to your roots. That’s why growers add things like perlite to their soil/coco, to make air pockets in the soil, or why they grow in fabric pots (lets air in from the sides). The less air the roots get, the slower the plant tends to grow. So when you have plants growing in relatively thick soil like pure composted soil without any perlite, the plants tend to grow slower than they would in an airy soil mix or hydro. That’s always why plants that are overwatered/droopy grow slower – the plant isn’t getting oxygen at the roots.
- Comfortable Temperature– Plants can’t stand freezing or incredibly hot temperatures (though some strains are bred for cold climates, while some from hot regions can handle the heat)
- Nutrients– If you’re growing in heavily amended soil, you may not need to add nutrients since they’ll be there in the soil. However, once a plant is in a pot for a while, it uses up a lot of the nutrients. Generally, if you’re growing your plant in a container and you’re not going to add extra nutrients, it’s recommended to transplant your plants to fresh soil periodically during its life, and especially right before flowering, to make sure your plant is getting what it needs. However, for the fastest growth, you can give nutrients to your plants directly in the water. This gives it the right ratios in the most easily absorbable form, so you don’t have to worry about running out. You don’t even need supplements to get really high-quality bud. Base nutrients are all you need to get to harvest with amazing results. The main thing about nutrients is your plants need lots of Nitrogen (N) in the vegetative stage (any all-purpose plant nutrients will do the trick) and then it needs high levels of Phosphorus (P) and Potassium (K) in the flowering stage (Flowering Nutrients, Cactus Nutrients or Bloom Boosters provide lots of P and K).
- Seeds (or Clones) – Obviously you need a cannabis plant
When it comes down to it, that’s all you really need to grow successfully. If you get an auto-flowering strain you don’t even need a timer or to worry about light schedules. Just plant the seed and wait until harvest.
I personally feel like growing in something like coco coir under a small HID light like a 250W MH/HPS or 315 LEC is one of the best ways to ensure good results the first grow if you’re just looking to grow 4-7 ounces.
The reason is that those lights are incredibly efficient and easy to understand how to use. With fluorescents like CFLs and T5s, the yields are relatively low for the electricity used, and with LEDs it can be really tough to get the light distance “dialed in.” It just adds a lot of variables that make it easy to burn your plants. I like how with the small HID lights you just keep the light about a foot away from the tops of your plants and forget about it, yet you still get those really dense and potent HID buds because of the light intensity. The small HID lights also don’t put out a whole lot of heat, so you don’t usually need to worry about an exhaust system unless you’re growing in a very small space without ventilation. A 250W HPS puts out about the same total amount of total heat as an LED that pulls 250W of electricity out of the wall.
Coco coir offers a great root environment with beautiful water-holding and drainage ability, so you get above average vegetative growth rates. Any hydro or coco nutrients made for cannabis will do a great job. Growing with coco coir will also teach you about pH and overall get you really familiar with the cannabis plant’s nutrient needs. By the end of a coco coir and small HID grow, you’ll have learned 80% of what you need to know about growing in either soil or hydro if you choose to do that down the road. You’ll also have a good base knowledge if you wanted to move onto bigger grows!
So what does a grower need? A grower needs to make a good environment for their plants with decent temperatures, bright light, and happy roots. Even if you don’t do anything else, you’ll be able to make it to harvest with really high-quality bud by doing just those things.
The last incredibly important thing is to always dry your buds slowly and cure them after harvest! A lot of growers skip those steps, but they are necessary to get buds with the best smell, smoothness and potency. If you just smoke buds directly off the plant it will taste horrible, give you a headache, hurt your throat and possibly not even really be potent! The dry/cure will dramatically increase the overall quality and appearance of your buds!
While we’re here…
What’s the secret to growing rock-hard nugs of weed?
- Light – and a lot of it! This may be the most important part. Your buds need direct exposure to bright light or they won’t grow. However, on the flip side, too much light will burn your buds so more is better, but only up to a point!
- Strain – choose a high-yielding, dense strain. Some strains, like many Sativas and Hazes, will never grow dense buds no matter what you do! Trying to get dense buds with the wrong strain can be a lesson in futility.
- Dry/Cure – Buds tighten up during the dry/cure process (plus it makes them smell better, smoke better and feel more potent!)
It will also help improve density if you trained the plant in the vegetative stage to grow just a few big buds at the top, as opposed to many smaller ones located throughout the plant.
Other than that, I think the main focus is keeping plants healthy and keeping the temperature down in the flowering stage (very high temps can cause loose buds and burn away potency/smell). Give plenty of light but avoid light burn. Not really related to adding density, but if you have dense buds you NEED to make sure you keep the humidity under 50% RH to prevent the chance of bud rot.