Updated October 3, 2026. Revised with a linked label-accuracy study, clearer recording guidance, and limits on what personal patterns and AI visual reports can establish.
You remember the great ones.
That flower that made an ordinary Friday night feel perfect. The edible that somehow hit exactly right. The vape you swore you'd buy again.
You probably remember the bad ones, too.
The problem is everything in between.
A few weeks later, the name is fuzzy. Was it 24% THC or 28%? Was that the one that made you relaxed—or the one that left you staring at the ceiling at 2 a.m.? What were the terpenes? Where did you even buy it?
And suddenly you're standing in a dispensary trying to make another decision from scratch.
That's exactly why keeping a cannabis journal can be so useful.
Not because every session needs to become a science experiment.
Because your experiences are data—and most of us are surprisingly bad at remembering that data.
What Is a Cannabis Journal?
A cannabis journal is a record of the cannabis products you've tried and your experience with them.
At its simplest, that could mean writing down:
What you used
How much you used
When you used it
How it made you feel
Whether you'd use it again
But a useful cannabis journal can go much further.
You can track the brand, product type, cannabinoids, terpenes, aromas, flavors, price, where you bought it, your mood, positive effects, unwanted effects, and anything else that helps put the experience into context.
Over time, those individual entries become something much more valuable:
your personal cannabis history.
Why Keep a Cannabis Journal?
Walk into a dispensary and you're surrounded by information.
Strain names.
THC percentages.
Indica.
Sativa.
Hybrid.
Terpenes.
Cannabinoids.
Brand names.
Budtender recommendations.
Packaging promising everything from relaxation to creativity.
The missing piece is you.
Two products can look similar on a menu and still produce very different experiences. Even the same product can feel different depending on dose, setting, timing, tolerance and the person consuming it.
That's why a cannabis journal shouldn't simply document cannabis.
It should document your relationship with cannabis.
Instead of asking:
What's the best strain?
Your journal eventually helps you ask a much better question:
What tends to work best for me?
That's a completely different way to buy and use cannabis.
1. Start With the Product
First, record exactly what you're consuming.
At minimum, track:
Product name or strain
Blue Dream, Permanent Marker, Gelato 41, or whatever is printed on the package.
Brand or cultivator
This matters more than many consumers realize. The same strain name doesn't guarantee an identical product from different growers or brands.
Product type
Flower, pre-roll, vape, edible, concentrate, tincture, topical, etc.
Where you bought it
Especially useful if you discover something worth buying again.
Price
Because a great experience at $30 and a mediocre experience at $60 tell you something very different about value.
Think of this section as creating the product's receipt in your cannabis memory.
Keep the Batch and the Session Separate
A product entry identifies what you have; a session records a particular use. Add the batch or lot, package and purchase dates, and matching COA date when available. Two sessions with one product can have different outcomes.
Record the amount with units and the method. For a labeled edible, note the portion and labeled milligrams consumed. For flower, record the amount used when known without pretending it is the exact absorbed THC dose. Add the start time, first noticeable effects, approximate peak, and duration. Mark estimates and unknowns honestly.
2. Record THC and CBD—But Don't Stop There
THC percentage dominates cannabis shopping.
It's easy to understand why.
One package says 19%.
Another says 27%.
Higher must mean better, right?
Not necessarily.
THC is useful information, but treating it like a universal quality score oversimplifies cannabis.
There's another reason to avoid putting too much faith in a single number: cannabis labels themselves aren't perfect. A 2025 Colorado study of 277 commercially purchased flower and concentrate products found differences between labeled and independently measured THC, particularly among flower products. Its results describe that sample and testing comparison, not every product in every market.
So record the THC.
Record the CBD.
Record total cannabinoids when they're available.
But don't allow one percentage on the package to become your entire understanding of the product.
The label and your experience answer different questions. Keep both.
3. Track the Terpenes
This is where cannabis journaling starts getting interesting.
Terpenes are aromatic compounds found throughout nature, including cannabis. They contribute to the aromas and flavors associated with different cultivars.
You've probably seen names like:
Myrcene
Limonene
β-Caryophyllene
Linalool
Pinene
If your package or Certificate of Analysis lists a terpene profile, save it.
You don't need to memorize terpene charts or decide that one terpene will always produce one specific effect. Human cannabis experiences are more complicated than that.
Instead, look for patterns in your own entries.
Maybe several products you loved shared similar terpene profiles.
Maybe products you disliked did, too.
There is no magic number of entries that makes a pattern reliable. More complete records can help you notice recurring observations, but repetition alone does not establish cause.
4. Write Down What It Actually Smells and Tastes Like
Don't outsource your senses to the package.
Smell the flower.
What do you notice?
Citrus?
Pine?
Earth?
Diesel?
Berry?
Sweetness?
Skunk?
Herbal notes?
Then do the same with flavor.
Your answer doesn't have to sound like a professional cannabis reviewer describing “sun-dried Meyer lemon over notes of Himalayan cedar.”
If it smells like lemon and gas, write lemon and gas.
The point isn't sophistication.
It's consistency.
Over time, you may discover that the aromas and flavors you're naturally drawn toward repeatedly show up in products you rate highly.
That's useful information.
5. Track How You Felt
This might be the most important part of the entire journal.
Don't just write:
“It was good.”
Good how?
Relaxed?
Happy?
Creative?
Focused?
Hungry?
Sleepy?
Talkative?
Euphoric?
Calm?
And don't ignore unwanted effects.
Did you feel anxious?
Foggy?
Restless?
Too sleepy?
Uncomfortable?
Dry-eyed?
Your negative experiences can sometimes teach you as much as your favorites.
A product you rated three stars isn't necessarily useless information.
It may be exactly what helps you avoid making the same purchase again.
6. Add Context
Cannabis doesn't happen in a vacuum.
Your experience can be influenced by what was happening around you.
Were you winding down after work?
At a concert?
Watching a movie?
Trying to sleep?
Hanging out with friends?
Already stressed?
In a great mood?
Trying cannabis for the first time that day—or consuming after several earlier sessions?
You don't need to record your entire biography every time you consume.
A sentence can be enough:
Long day. Wanted something relaxing before bed.
Or:
Saturday afternoon with friends. Wanted to feel social without getting too heavy.
That little bit of context can become incredibly useful when you look back later.
7. Give It a Rating
Finally, answer the simplest question:
How much did you actually like it?
A five-star rating works perfectly.
★★★★★ — I'd actively look for this again.
★★★★ — Really good.
★★★ — Fine, but nothing special.
★★ — Probably wouldn't buy again.
★ — Definitely not for me.
Then add a quick note explaining why.
Don't overthink it.
Your journal is for you.
How to Review Your Entries
This is where cannabis journaling becomes much more powerful than keeping a list of strain names.
You may begin to notice patterns.
Maybe your highest-rated flower isn't actually your highest-THC flower.
Maybe several favorites came from the same cultivator.
Maybe certain terpene profiles keep appearing in products you enjoy.
Maybe the same product felt different across times, amounts, or settings.
Maybe you've spent hundreds of dollars repeatedly buying cannabis that looked great on paper but rarely delivered the experience you wanted.
That's information you can use.
The goal isn't to turn cannabis into a spreadsheet.
The goal is to stop starting over every time you shop.
Paper Journal, Notes App or Cannabis Journal App?
Choose a format you can maintain comfortably.
A notebook works.
Your Notes app works.
A spreadsheet works.
Take photos of packages if that's easiest.
The important thing is creating a record you'll actually maintain.
But once you've accumulated dozens of products, manually searching old notes becomes cumbersome. That's where a dedicated cannabis journal can become useful.
Green Journal was built around exactly this problem.
Instead of scattering your cannabis history across screenshots, packaging, notes and your memory, Green Journal lets you keep products and experiences together.
You can track products, ratings, effects and moods; save cannabinoid and terpene information; scan packaging; import available lab information; review visible flower presentation; and eventually look back at the patterns across your history.
The point isn't simply to collect more cannabis data.
It's to make that data useful.
Your Memory Isn't a Cannabis Database
The cannabis industry gives consumers more information than ever.
But more information doesn't automatically mean better decisions.
A strain name can't remember how you felt.
A THC percentage can't tell you whether you enjoyed the product.
A beautiful package can't tell you whether you'd spend $45 on it again.
Your history can.
That's what makes a cannabis journal powerful.
Every entry answers one small question:
What happened when I tried this?
Over time, those answers can help you understand something much bigger:
what you have noticed about your own experiences.
Know your weed. Know yourself.
Protect Context and Privacy
Record your starting mood or symptoms before use when practical, not only afterward. Keep private health details out of public reviews unless you deliberately choose to share them. Check photos and receipts for addresses or other information before posting.
Personal entries are observational. They can support memory and a conversation with a healthcare professional, but they cannot diagnose a condition or prove a treatment effect. AI can also make mistakes. A flower-photo report does not verify potency, contamination, safety, or future effects, and imported information should be reviewed before saving.
For the evidence behind category and terpene claims, see our updated strain-label guide.
GREEN JOURNAL · THE APP
Your next favorite is worth remembering.
Keep your products, sessions, ratings and personal notes together. Spend less time trying to remember—and more time learning from your own history.
Download Green Journal for iPhone & iPad ↗
Free to download. Optional in-app purchases.