CANNABIS STRAINS
From 1:1 balanced cultivars to 50:1 hemp-derived CBD products — the definitive guide to CBD-dominant cannabis strains, how they work, and how to choose the right ratio for your needs.
High-CBD cannabis refers to cultivars in which cannabidiol (CBD) is the dominant or co-dominant cannabinoid. For most of the 20th century, commercial cannabis was selectively bred for maximum THC content, and CBD was inadvertently eliminated from most commercial gene pools. CBD is coded by a distinct allele at the same genetic locus as THC — strains expressing CBD do so instead of, or alongside, THC.
A strain is generally considered “high-CBD” when it contains 4% CBD or more. Medical dispensaries typically stock CBD-dominant flower in the 8–15% CBD range. Industrial hemp cultivars bred specifically for CBD extraction can reach 18–22% CBD with less than 0.3% THC.
The most clinically relevant metric is the CBD:THC ratio, not the absolute CBD percentage. A 10% CBD strain with 10% THC (1:1 ratio) will produce a very different effect than a 10% CBD strain with 1% THC (10:1 ratio), despite identical CBD content.
CBD’s pharmacology is substantially more complex than THC’s. Where THC acts primarily as a direct agonist at CB1 cannabinoid receptors (producing intoxication), CBD engages a broader array of receptor systems with different clinical implications.
CB2 Receptors: CBD modulates CB2 receptors concentrated in immune tissue and the peripheral nervous system. CB2 activation reduces the release of pro-inflammatory cytokines including IL-1β, IL-6, and TNF-α, explaining CBD’s anti-inflammatory applications in conditions from arthritis to neuroinflammation.
5-HT1A Serotonin Receptors: At concentrations achieved with higher CBD doses, CBD acts as a 5-HT1A partial agonist. This receptor is the primary target of many anxiolytic and antidepressant drugs. CBD’s activity at 5-HT1A underpins its anti-anxiety effects and potential in PTSD and social anxiety disorder.
TRPV1 Ion Channels: CBD activates and desensitises TRPV1 (transient receptor potential vanilloid 1), a pain-signalling ion channel. This vanilloid pathway contributes to CBD’s analgesic effects independently of the opioid system.
GPR55 Antagonism: CBD acts as an antagonist at GPR55, a receptor associated with inflammatory pain and potentially with cancer cell migration. GPR55 blockade is an active area of oncology research.
CB1 Negative Allosteric Modulation: CBD reduces the binding efficiency of THC at CB1 receptors without blocking the receptor site. This is why high-CBD strains with moderate THC produce less intoxication than equivalent-THC strains without CBD.
| Condition | Evidence Quality | Recommended Form | Key References |
|---|---|---|---|
| Epilepsy (Dravet/LGS) | High — FDA-approved drug | CBD isolate oral solution (Epidiolex) | Devinsky 2017 NEJM; Devinsky 2018 NEJM |
| Anxiety | Moderate (RCTs + case series) | Sublingual oil; high-CBD flower | Bergamaschi 2011; Shannon 2019; Blessing 2015 |
| Neuropathic Pain | Moderate (Cochrane 2018) | 1:1 preparations; sublingual | Whiting 2015 JAMA; NNT ~5–11 (nabiximols) |
| Inflammation | Moderate (preclinical + observational) | Full-spectrum flower or oil | Russo 2011; CB2 cytokine studies |
| PTSD | Emerging (open-label, observational) | CBD-dominant; moderate THC | Elms 2019; Jetly 2015 |
| Insomnia | Low–moderate (mixed data) | Evening flower; 1:1 or CBD-dominant | Shannon 2019; indirect via anxiety reduction |
| Strain | CBD% | THC% | Ratio | Flavor | Primary Use |
|---|---|---|---|---|---|
| ACDC | 14–20% | <1% | 20:1+ | Earthy, pine, woody | Anxiety, pain, seizures |
| Harle-Tsu | 18–22% | <1% | 20:1+ | Earthy, sweet | Inflammation, seizures |
| Canna-Tsu | 10–15% | 5–10% | 1:1–2:1 | Earthy, sweet, citrus | Anxiety, pain, daytime |
| Harlequin | 8–16% | 4–7% | 5:2 | Mango, earthy, woody | Pain, focus, low anxiety |
| Cannatonic | 6–17% | 5–7% | 1:1–3:1 | Earthy, pine, citrus | MS, anxiety, pain |
| Sour Tsunami | 10–13% | 1–10% | 1:1–10:1 | Diesel, woody, sour | Pain, neuropathy |
| Penelope | 12–15% | 4–6% | 4:1 | Earthy, floral, spice | Focus, inflammation |
| Ringo’s Gift | 10–24% | <1% | 20:1+ | Earthy, sage, citrus | Anxiety, epilepsy |
| Charlotte’s Web | 17–20% | <0.3% | 50:1+ | Earthy, olive, woody | Pediatric epilepsy, hemp |
| Remedy | 14–18% | <1% | 15:1+ | Lemon, earthy, pine | Pain, PTSD, anxiety |
| Elektra | 15–20% | <0.3% | 50:1+ | Citrus, floral, pine | Hemp; everyday wellness |
| Critical Mass (CBD) | 8–12% | 5–8% | 1:1 | Sweet, earthy, citrus | Pain, sleep, balanced |
| Dancehall | 15–18% | 5–9% | 2:1 | Sweet, earthy, citrus | Daytime, social anxiety |
| Stephen Hawking Kush | 8–13% | 5–8% | 1:1 | Berry, cherry, earthy | Pain, nausea, evening |
| CBD Kush | 8–12% | 5–8% | 1:1 | Earthy, spice, kush | Relaxation, sleep, pain |
| Ratio (CBD:THC) | Psychoactivity | Best For | Drug Test Risk |
|---|---|---|---|
| 1:1 | Moderate, manageable | Pain, sleep, MS, balanced recreational | High — significant THC present |
| 2:1 | Mild, functional | Anxiety, daytime pain, PTSD | Moderate — THC metabolites detectable |
| 4:1 | Very mild, near-functional | Anxiety, inflammation, neuropathy, focus | Lower — low but non-zero THC |
| 10:1 | Minimal | Seizures, severe anxiety, daily wellness | Low with moderate use |
| 20:1+ | None detectable | Epilepsy, children, sensitive consumers | Very low (trace THC) |
| 50:1 (hemp) | None | General wellness, OTC products | Very low if properly tested; isolate safer |
The Agriculture Improvement Act of 2018 (the “Farm Bill”) created a legal distinction between hemp and marijuana based entirely on THC content. Cannabis plants containing 0.3% or less THC by dry weight are classified as hemp and are legal to cultivate, process, and sell federally. Cannabis plants above 0.3% THC remain Schedule I controlled substances under the Controlled Substances Act.
In practical terms: CBD products derived from hemp (Charlotte’s Web, Elektra, most retail CBD oils) are federally legal and available in all 50 states. CBD flower from a high-CBD cannabis cultivar (ACDC, Harlequin, Canna-Tsu) is only legal in states with medical or recreational cannabis programs, even if the THC content is very low, because the plant itself exceeds 0.3% THC.
This creates a regulatory anomaly where a 10% CBD, 8% THC cannabis strain is Schedule I federally, while a 20% CBD, 0.2% THC hemp cultivar is fully legal despite producing nearly the same CBD dose per gram.
| Form | Bioavailability | Onset | Duration | Best For |
|---|---|---|---|---|
| Smoked flower | ~31% | 1–3 min | 1–3 hr | Acute anxiety, pain spikes |
| Vaporised flower/oil | ~34–46% | 1–5 min | 1–3 hr | Precision dosing; lung-safer than smoke |
| Sublingual oil (held 60–90 sec) | ~13–19% | 15–45 min | 4–6 hr | Daily maintenance dosing; consistent levels |
| Oral capsule (swallowed) | ~6–10% | 60–120 min | 6–8 hr | Sleep; consistent overnight coverage |
| Topical cream/balm | Skin-local only | 15–45 min | 4–6 hr locally | Localised inflammation; joint pain; no systemic effect |
A critical practical concern for consumers in employment contexts: high-CBD cannabis flower will cause a positive drug test. Standard workplace urine panels (SAMHSA 5-panel and NIDA guidelines) test for THC-COOH, the urinary metabolite of THC, at a 50 ng/mL initial screening cutoff with GC-MS confirmation at 15 ng/mL.
Even a strain with 10% CBD and only 5% THC delivers substantial THC to the body when smoked or vaporised. Regular consumption of a 2:1 CBD:THC strain will produce positive urinalysis results in most consumers. Detection windows follow standard THC patterns: casual use 3–4 days, moderate use 5–7 days, daily use 10–30 days depending on body fat percentage and metabolism.
Only CBD isolate products verified by third-party COA to contain zero detectable THC are genuinely safe from a drug testing standpoint. However, Bonn-Miller et al. (2017) in JAMA found that 26% of commercially purchased CBD products were mislabelled for THC content, and some contained enough THC to produce a positive test. Consumers in safety-sensitive employment should consult an occupational health specialist before using any cannabis-derived product.