How To Increase CBD Levels When Growing Weed
4 min

How To Increase CBD Levels When Growing Weed

4 min

CBD has become a superstar of the cannabinoid family in recent years. Although clinical trials are limited, preliminary research points to intriguing effects on the human body. A wealth of anecdotal accounts support various uses of the cannabinoid, and science is beginning to elucidate more of the specifics.

Media coverage of these results has turned the heads of traditional breeders—those who, up until now, were previously in pursuit of ever-increasing THC levels. The tables have turned slightly, and growers are presently seeking to encourage higher concentrations of CBD in their plants. But how do you achieve this as a home grower? In this article, we'll share some simple tips for increasing the CBD levels of your next harvest.


CBD was first identified by researchers from the University of Illinois in the 1940s. Since then, limited research has uncovered the very basics of CBD’s mechanism, and resulting action, on the human body. The cannabinoid is known to indirectly influence the endocannabinoid system—a regulatory network that affects mood, appetite, pain, memory, and more. CBD is also believed to exert some of its effects via numerous other molecular targets, including serotonin and vanilloid receptors.

We’ll explore some of the research on CBD below. Keep in mind that even clinical trials have their limitations. Still, the results of these studies are a major contributor to the abundance of home growers interested in cultivating CBD-rich cannabis.


What Are The Potential Benefits Of CBD

Several studies have examined the effects of CBD on various models of anxiety. A clinical study published in the journal Neuropsychopharmacology examined the impact of CBD on social anxiety disorder during a simulated public speaking event. Subjects that received 600mg of oral CBD displayed significant reductions in anxiety and discomfort during the speech when compared to placebo.

Additional research explored the neurological effects CBD produces in models of anxiety. Researchers scanned the brains of 10 patients with social anxiety disorder after administering CBD. They found significant reductions in anxiety, which they believe to be linked to reduced blood flow to areas of the brain, including the hippocampus.

CBD has also shown impressive antiseizure potential in children with specific forms of severe childhood epilepsy. A clinical trial published in The New England Journal of Medicine investigated the effects of CBD on Dravet syndrome—a severe form of childhood epilepsy. The double-blind, placebo-controlled trial involved 120 children and young adults with the condition. Participants received a CBD oral solution of 20mg per kilogram of body weight each day, or placebo. It was found that CBD resulted in a more significant reduction in seizure frequency when compared to placebo.

Moreover, the US FDA has approved a CBD oral spray called Epidiolex to treat Dravet syndrome and another form of severe childhood epilepsy, Lennox-Gastaut syndrome.

The above examples represent just a glimpse of CBD’s potential. We chose to highlight areas where some degree of human research has been conducted, as much of the current body of literature has been conducted on animals or cell models. This doesn’t mean CBD has no potential in these areas—just that it’s much too early to fully confirm or deny.


So, we’ve covered some of the essential benefits of CBD. Now, here are some simple tips for increasing CBD levels in your next harvest. Remember, if you’ve got tips that we don’t cover here, make sure to share them with us!



If you’re looking to produce a CBD-rich harvest, it’s vital you work with the right strain. Working with a strain known to contain high levels of CBD is by far one of the easiest ways to guarantee you get the right results. Today’s most popular seedbanks will offer a few CBD-rich varieties, and you’ll find most of them in our seedshop, where you can buy the best cannabis seeds online. You can find our top 3 picks here below.


Dinamed CBD (Dinafem): This is one of Dinafem’s flagship medical strains. A sativa-dominant hybrid, Dinamed CBD shows consistently high levels of CBD, usually clocking in at around 14%. It is suited for both indoor and outdoor grows, and flowers in just 60 days. Best of all, with only 0.5% THC, this is a great strain for patients or consumers who want to avoid the psychoactive effects associated with regular weed.

Candida CD-1 (Medical Marijuana Genetics): Candida CD-1 is an extremely popular medicinal cannabis strain, boasting one of the highest CBD concentrations of any strain currently on the market (up to 20%). It is known to produce two unique phenotypes, an indica and a sativa. Candida CD-1 tends to flower in just 9 weeks and contains less than 1% THC.

Cannatonic (by Resin Seeds): Cannatonic by Resin Seeds is a medical marijuana strain with a 1:1 CBD:THC ratio. It is also a 50-50 hybrid strain that produces decent harvests in just 7-8 weeks. Unlike the previous two strains, this strain does contain notable concentrations of THC, meaning it may produce some psychoactive effects.

High CBD Strainsview High CBD Strains


2. Ward Off Disease And Pests

Like any other plant, cannabis is susceptible to a variety of diseases and garden pests. When left uncontrolled, these intruders can stunt plant development and ultimately affect the potency of its harvests (just like with regular THC-rich strains). Hence, its extremely important you keep a close eye on your plants throughout their entire growth cycle, and deal with any pests/diseases as soon as possible. Some common cannabis pests and diseases to look out for are broad mites, spider mites, bud/root rot, yellow leaf spot, whiteflies, and tobacco mosaic virus.

Most of these can be avoided by keeping your plants at optimal temperatures (18-28°C) and humidity levels (40-70%). Proper lighting and ventilation also help regulate temperature and humidity around your grow room, which is really important for preventing these threats.

Finally, you’ll also want to make sure your grow room is always clean and sterilised. 


3. Harvest At The Right Time

The time you decide to harvest can have a huge effect on the cannabinoid concentrations of your finished product. To pick the right harvest time, it’s best to look to your plant’s trichomes. This can be done by using a magnifying glass or jeweler’s loupe. When seeking high concentrations of THC, you’ll usually want to harvest when most of the trichomes have turned from translucent to milky.

When it comes to CBD, however, opinions vary. Unfortunately, there is little official literature on harvesting time for cannabis plants. Most growers will agree that CBD tends to peak before THC, and therefore, it's better to harvest slightly early. Some CBD growers will harvest as soon as trichomes are only partially cloudy. Others will wait even longer.

Remember, these are just general rules. The peak harvest time will vary from one strain to another, and may also change slightly depending on your grow conditions. As you gather more experience with growing CBD-rich cannabis, you’ll become more familiar with the individual plants you’re growing and their peak harvest time.


Other Theories On Increasing Cbd

There are many theories on how to increase CBD concentrations in cannabis plants. Some growers believe that a combination of warm temperatures (both in the soil and grow area) and low precipitation can also boost the CBD levels of your next harvest. Unfortunately, there is no official studies to confirm whether these methods actually work. Nonetheless, feel free to try such theories for yourself and share your results with us so we can pass them on to the rest of the community!

Steven Voser
Steven Voser
Steven Voser is an independent cannabis journalist with over 6 years of experience writing about all things weed; how to grow it, how best to enjoy it, and the booming industry and murky legal landscape surrounding it.
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