It’s a problem just about everyone has faced: Dry weed. First-time growers are definitely familiar with overly-dry buds that crumble to dust in your hands (learn how to dry and cure cannabis here). The smoke is harsher, and the burn is faster — it’s just not a good situation. Even buds that are perfectly cured can wind up dried out if they’re left exposed to dry conditions for just a few hours. Why? Physics! But there’s an easy fix for all this if your buds wind up turning to powder every time you touch them.
First, the science behind evaporation is quite simple. Water evaporates when exposed to the air, unless that air is dripping with moisture. Even then, the water in your buds will evaporate because the water in them and the water outside them aren’t in equilibrium. The molecules of water can “escape” even at low temperatures! Water is a wondrous thing, and evaporation can take place even when it has become a solid, also known as ice. Basically, water is just yearning to be free and will help itself to freedom if — for whatever reason — you’ve exposed your marijuana buds to the air.
How do you protect your stash from becoming dry and brittle? Storing your buds properly is 99% of the battle here. You want to keep them in air-tight containers, and away from light sources (particularly UV light, like the sun). Glass is better than plastic bags because it can seal better, but it’s also a good idea to store buds in smaller containers. Part of the reason you’re finding dry weed at the end of a jar might be because you’re using a giant jar. Every time you open that jar, a little water escapes. Over time, the last bits will naturally be drier than when it was fresh. So ideally if you buy in quantity, break it down into smaller jars and try to minimize exposure to air and light.
By the way, there are cannabis humidors just like cigar smokers have enjoyed for decades. These are designed to keep your flowers fresh and properly hydrated for longer, and can range from a simple box with cedar lining and a hygrometer to check on the relative humidity to Bluetooth-enabled devices that can tell you from an app just how moist those buds are. A cheaper method is to use humidity packs, like those sold by Boveda, to keep weed fresh. These are sort of like those silica gel packs you find in boxes to keep things dry when they’re shipped in cargo containers, but the Boveda packs keep the optimal humidity in whatever you’ve got your weed in.
Luckily it’s not too hard to re-hydrate your buds, provided you’re patient. Just as dehydration can be a slow process, so too is re-hydration. We’re not making tea here. Instead, you’re going to seal moisture in a container with your dry cannabis. After a bit, the cannabis will absorb the moisture and be “fresher” for it. The best idea is to use distilled water, since it has had the impurities taken out. Take a paper towel and get it damp with the distilled water, but not dripping wet. Something you’re hoping to avoid is mold on the buds. Put the paper towel and your buds in a sealed container (it can be plastic, glass, or anything that will truly be airtight). Leave them alone for several hours, up to 12 if everything is very dry. This should help! You can also try fruit peels instead of the paper towel, and orange or lemon peels can imbue the buds with a slight citrus flavor. Some say you can also use crisp iceberg lettuce, as it is packed with water and won’t leave any “taste” profile behind.
Keep in mind it’s not good to dry, re-hydrate, and dry again your buds. Over time, these will develop mold, which ruins the flowers. But if you’ve awakened to an open jar that dried out overnight, a rehydration isn’t a bad idea once in a while. The best thing to do is keep your buds in airtight containers and prevent them from drying out to begin with.