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How to Grow Hemp
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Hemp Terminology
Before we begin, it’s important to understand the terminology surrounding hemp and cultivating it. More so, the fact that hemp and marijuana are considered by botanists to be the same plant: Cannabis sativa.
The term hemp comes about in concerns to the cannabinoids found in the cannabis plant. More specifically, the tetrahydrocannabinol (THC) count. By federal law, a cannabis plant can only be deemed hemp if it contains less than 0.3% THC.
That said, it’s essential to ensure you’re purchasing hemp seeds rather than cannabis seeds. Depending on where you live in the United States, this could be the difference between following the law and giving yourself a felony.
Luckily, as we’ll get into, the best online seedbanks inform their customers of what’s in their seeds. More so, the cannabinoid count and whether or not they’re purchasing marijuana or hemp seeds.
Difference Between Male and Female Plants
On top of knowing the difference between cannabis seeds, it’s vital you can tell male and female plants apart. This importance will depend on why you’re growing hemp:
- Female plants produce hemp flowers that are rich in CBD. Furthermore, fertilized female plants will produce seeds.
- Male plants don’t have much use beyond hemp fibers, which can also be gathered from female plants.
With these descriptions, it comes as no surprise most cultivators are solely seeking out female plants. In any given batch of germinated hemp seeds, you’re likely to come across 50% females and 50% males.
However, you can ultimately increase your chances to 100% females simply by purchasing feminized seeds.
Still, if you don’t take this route, it can help to do a bit more research concerning the differences between male and female plants. More specifically, it’s worth looking into images of both and familiarizing yourself with their unique features.
How to Grow Hemp: Step-by-Step Guide
Step 1: Germinate the Seeds
Germinating hemp seeds is as simple as germinating tomato seeds. The process is as follows:
- Pre-soak seeds for 8 to 12 hours (this helps to ameliorate germination)
- Keep seeds at a temperature of 65 to 70 °F (18.33 – 21.11 °C)
- Once germinated, plant seeds into 1-inch deep soil (make sure the soil is moist)
- For further control, use a heat mat and thermostat
- Use a humidity dome (or DIY similar) to continue the germination process
Once this process is complete, you’ll want to then provide the best care possible for your seedlings. In more detail, this means:
- Keeping your planted germinated seeds at a temperature of 68 to 77 °F (20 – 25 °C). The best way to do this is through a heat mat.
- Maintaining humidity (preferably through a humidity dome) at a range of 65% to 70%.
- Placing High-Output LEDs or High-Output T5 fluorescent grow lamps several inches above seedlings (ensure this is aligned with the temperature of your heat mat).
- Keep these lights on 18 to 24 hours a day.
- Incorporate fertilizer that’s rich in nitrogen and has a target 3:1:2 NPK ratio.
Admittedly, some of these steps will require extra purchases (including feed and fertilizers). For this reason, you’ll want to consider exactly what you’ll need prior to germinating your seeds.
Step 2: Transporting Your Hemp Seedlings
Once you can see the seedlings’ roots on the bottom of the container, you’ll want to transfer them. Preferably, into a 4- to 5-inch container with a transplant mix.
When the roots have reached the bottom of this container, you’ll want to transfer them once again to their final growing container.
During this phase (known as the “vegetative stage”), there are a few specifics you’ll want to ensure for optimal plant health:
- When the plant is in its younger, vegetative state, you ideally want to keep it at a temperature of 70 to 82 °F (21.1 – 27.8 °C). Once the plant has grown some, they prefer temperatures of 60 to 80 °F (15.5 – 26.6 °C).
- During the vegetative stage, plants prefer a humidity range of 40% to 70%.
- When non-flowering, you’ll want to continue leaving lights on 18 to 24 hours a day.
- Continuously water plants so the soil remains moist. On top of this, continue to implement nitrogen-rich 3:1:2 NPK ratio fertilizer.
Step 3: The Flowering Stage
When it comes to growing hemp, the flowering stage is often touted as the most important. This is when your plants will begin to grow buds and these also require precise care:
- Mature plants prefer a temperature range of 68 to 77 °F (20 – 25 °C).
- You’ll want to ensure air is constantly moving through your growing area. This helps to ensure pests and germs will not contaminate your plants.
- Once your plants begin to bud, you’ll want to keep them on a 12-hour light and 12-hour darkness schedule. During the darkness period, make sure the plant is completely blocked out of sunlight – even the tiniest amount of light can damage a plant.
- Keep plants watered just enough so they don’t dry out. It’s important to ensure you’re not overwatering in this stage.
- In order to support the flowering process, you’ll want to feed your plants with a liquid fertilizer that contains a target NPK ratio of 1:3:4.
How to Grow Hemp FAQs
In accordance with the 2018 Farm Bill, it’s technically legal to grow hemp anywhere in the United States. However, each state has their own rules and regulations concerning hemp cultivation. For more information on your state, click here.
Since hemp is such a hardy plant, it can be grown anywhere. However, it’s optimal to grow hemp indoors in a controlled environment.
Yes! Hemp flower tends to be higher in cannabidiol (CBD) than any other cannabinoid. It’s worth noting that some hemp seeds are genetically modified to contain more CBD than others.
