The Shelf Life Of Weed: How Long Does Flower Stay Fresh?

What to do when you find an ancient bag of dope in your parents' basement.

Here’s a true story: Lately, I’ve had a lingering urge to make some cannabutter (my mom’s recipe—coconut oil infused with cannabis by way of a long, slow simmer). But with an expired medical marijuana card, and no giant bags of shake to be found in the depths of my weed box, I found myself at a loss. Then, while cleaning out the clustercuss that is my pantry, I found a generously sized bag of the kind of homegrown-scraggle-weed that’s perfect for home-brewed butter.

The only problem? The bud was as crisp as a mummified box of saltine crackers, a relic of my freeloading college days. Which led me to ask myself a bunch of questions: If I try to grind this ancient herb, will it turn to dust? Will it work? Will I die? Is this even weed?

Look, I’m no expert, but I do know how to use the Google, and figured out how to change a tire once, so I felt that I was up to the task of digging deep into the science behind keeping cannabis fresh.

Here’s what I found:

As is the case with most of the organic elements on earth––and personal relationships for that matter––nothing lasts forever. Everything is temporary. My apologies if you’re first hearing about mortality via this cannabis lifestyle and news media website, but hey, there are worse ways to learn of death. Generally, when treated right, weed can keep for a good six months to a year. Now, after that date, it’s not as if smoking some dusty weed will kill you. In fact, it might not do much of anything. In the same way other drugs and even spices in your pantry lose potency over time, your old herb won’t give you the same lift as that hot, young herb. It’s an ageist, terrible reality, but it is what it is.

But exactly how shitty will your weed be if you forget about it all year, you ask?

Image via Flickr

The United Nations Office on Drugs and Crime has a solid answer. Basically, the gradual loss of THC in stored cannabis is proportional to the amount of time your weed sits in storage. Overall, the study’s authors found that after one year of being kept at room temperature, your flower’s THC content will decrease by about 17 percent. After two years, you’re seeing a 27 percent loss in potency; three years brings you a 35 percent drop; and by four years, your weed is almost half as potent as it once was. So, say you start off with a nice, potent, Blue Dream, which was lab-tested at 33 percent THC. Store those flavorful nugs in your bedroom for four years, and the weed will probably just put you to sleep.

It’s not bad to smoke geriatric ganga, but I wouldn’t necessarily call it good either.

Cannabis is different from a fine wine, in that it won’t always get better the longer it is aged. Though like fine wine, you want to store your nugs in a cool, dark place. Your mom’s basement will do just fine. One of those nifty marijuana humidors would be perfect. And Buffalo Bill’s lotion pit works, too, if being a creeper is more your style.

To sum it up, keep your weed out of the sun if you want to get high.

But if you want to make that weed last—whether you’re a slow burner or prepping for the Apocalypse—there are a couple key tricks to keeping it tight. For instance, avoid too-large of containers, paper anything, or plastic baggies that get punctured easily, and aren’t particularly airtight anyway. So much for my hidden pantry weed. Sigh.

On the flipside, glass and ceramic jars are great for weed storage for a variety of reasons. (Just Herb knows what's up.) According to Merry Jane, you can get a good seal with jars and they generally maintain proper humidity levels. Should you want to get super fancy, grab your mom’s vacuum sealer and zip those puppies up like a Space Bag infomercial. 

To sum it up, keep your weed out of the sun if you want to get high. Sunlight degrades THC, converting it to the non-psychoactive cannabinoid, CBN #science. That being said, CBN contains beneficial properties of its own, and is believed to help patients with sleep, pain, inflammation, and reduced appetite, Leafly reports. Some dispensaries have started offering concentrated forms of CBN for those looking beyond CBD to manage their pain. At the end of the day, it seems weed is the wonder drug we all think it is—even when treated with more neglect than your old Tamagotchi.