Our biggest desire as marijuana growers is to harvest the heaviest and most potent gooey, fat, sticky buds. We want the highest amounts of THC and other cannabinoids, along with terpenoids and flavonoids, per gram of bud. These compounds get you high and medicate you, and although cannabis leaves and other plant parts contain these compounds, cannabis resin glands are the real deal. They have by far the highest concentration of THC and other target cannabis compounds.

There are several types of resin glands but the most stony ones develop at the beginning of peak bloom. They consist of a clear stalk with a clear round resin head on top, like a golf ball on a tee. In some strains due to genetics, and/or stressful conditions, some cannabis plants produce a high percentage of unstalked glands that sit on or close to the leaf surface.

Marijuana growers want to grow as many resin glands as possible per gram of plant material. They also want their resin glands to be as fat, fresh and intact as possible at harvest time. Here are sure-fire strategies for getting more resins from your cannabis:

  • Choose cannabis strains known for heavy resin production. Many of us have grown legendary strains including Hashplant, White Widow and Gorilla Glue that are known for producing a high density of extra-large resin glands. Many of the high-resin strains are Indica dominant, but a few are Indica-Sativa hybrids or even Sativa dominant. Carefully study breeder strain descriptions, and query breeders, to determine exactly how resinous specific strains are alleged to be.
  • Grow room environmental conditions should be as close to ideal as possible. When your plants are growing in the correct ranges for temperature, relative humidity, vapor pressure deficit, carbon dioxide (C02), air exchange, and air movement, they’re more able to focus their energy on creating resins. Protecting your plants from predatory organisms such as gray mold, powdery mildew, fusarium, spider mites, thrips, broad mites, aphids also enhances plant health and resin production.
  • Feed program inputs you give your marijuana plants have a significant impact on activating the plants’ genetically-programmed resin-production tendencies. Using the highest quality bloom phase base nutrients in the right concentrations delivered in reverse osmosis water with the correct pH is absolutely essential. Other bloom phase feed program resin gland boosters include potassium silicate, a bloom booster with the right ratio of phosphorus and potassium (more potassium, less phosphorus), humic and fulvic acids, root zone carbohydrates.
  • Provide a healthy, living root zone environment for your cannabis roots. This is easier to do using veganic or organic rather than hydroponics nutrients. When you install beneficial bacteria and fungi in your root zone and feed those microbes with carbohydrates, it creates an enhanced, supercharged root mass and a hormonal symbiosis that boosts resin production.
  • Utilize the full range of electromagnetic grow light radiation. Although more research needs to be done, initial science indicates that ultraviolet light applied for a couple of hours just before lights-off spurs increased cannabinoid and terpenoid production. There are several ultraviolet grow light manufacturers claiming that their UV-A, UV-B or UV-C ultraviolet tubes or LED chips increase resin production. Most of them are scams. The ones we’ve tested that work well are from California LightWorks. You need to get them very close to your plants, and start dosing the plants for two hours at the end of the lights-on cycle beginning in early peak bloom. Watch out for bleached leaves.
  • Controller-driven LED grow lights with adjustable spectrums give you the option of adjusting red, blue and white color bands so you maximize resin production. You can’t do this with non-control LED grow lights or with high-intensity discharge bulbs. California LightWorks is making the most reliable LED grow lights controller, ultraviolet resin-booster units, and grow light combos we’ve tested.

After you’ve worked hard pushing your cannabis plants to give you the most resins their genetics will allow, you want to harvest at just the right time, and treat your resin glands like fragile eggshells containing psychoactive goo.

We’ll do a separate article on harvest timing because it’s a huge topic, but the summary is that the best way to time your harvests is to study your resin glands with a magnifying device beginning a couple of weeks before the seed breeder says the strain’s bloom phase should be over.

Peak bloom resin glands are crystal clear with erect stalks and intact round heads. Take a look at the resin glands in the photo at the top of the article. They’re in almost-perfect condition with just a little deterioration. In my grow room, the resin glands on that bud indicate harvest is only a week or two away.

When you see more than 10-20% of your resin glands collapsing or turning amber and cloudy, your buds are at peak potency and starting to degrade. Time to harvest—unless you like super-sedating overripe resins with amber or all-cloudy resin glands.

Avoid roughly handling buds during harvesting, drying, trimming, curing, bottling, and consumption. Using grinders, grabbing buds, crushing them, drying/curing/storing them in less than ideal conditions and other careless actions shatter and desiccate resin glands, leading to oxidation and other degradation of resins.

Buds should be dried and cured in a temperature range of 74-78°F with a relative humidity of 45-52%. The drying room should have microfiltered air, sufficient air exchange and air movement, and the buds should dry and cure in darkness, not under grow lights or in sunlight.

Constantly monitor buds for molds and mildews during drying, curing and storage. Starting in the middle of peak bloom phase and continuing throughout drying, curing and storing, dose your buds with UV-C light to kill powdery mildew, gray mold and other harmful organisms. CleanLight, the world’s leading UV-C company designing ultraviolet devices for cannabis crop protection says an added benefit is that UV-C light has been shown in initial testing to boost resin production.

Get cigar hygrometers and place them in your bud storage containers. Many growers overdry their buds, which compromises resins. Others underdry them, which leads to storage mold and other problems. Experiment with storage conditions inside containers of between 50-57% relative humidity to see the dryness you prefer for your buds. Thick and gooey buds might need lower relative humidity than thinner buds, for example.

Properly dried and cured buds stored in stainless steel or glass containers in the freezer hold at least 81-93% of their potency after one year of storage. Those same buds stored in the non-freezer part of the refrigerator retain at least 65-81% of their potency after one year. Buds stored outside a refrigerator, especially in conditions higher than 75°F, can lose nearly half if not more of their potency in a year.

When you’re ready to consume your cannabis, take it out of the freezer and carefully break up just the amount of bud you want to consume. Don’t crush resin glands; don’t use grinders.

If you have a lot of buds and not enough room to store them all, process them into hashish using ice water “bubblebags” or dry sift boxes. You can condense a pound of buds into pure or nearly-pure resin glands quite easily. Hashish should be stored in your freezer.

Now you know the best methods for increasing production of THC, other cannabinoids, and terpenoids in your marijuana garden, and for preserving them without degradation before you inhale them.

And speaking of inhaling, use a vaporizer rather than combustion. It’s better for your respiratory tract, the high is cleaner, and you use less cannabis per session.