The life cycle of a cannabis plant, from seed to store

TORONTO -- Licensed cannabis producers are ramping up production to address shortages that have plagued the pot market since legalization in October, but the time required to grow the average marijuana plant means consumers likely have a few more weeks to wait.

Cannabis lives up to its nickname and grows like a weed, but the plant needs as many as 18 weeks to progress from seed to harvest before it even moves on to processing and packaging.

Licensed producer CannTrust walked The Canadian Press through their cultivation and processing facilities to get a close look at the process. Here are the various life stages of the cannabis plant: from seed to plant to processing and packaging.

1) Seed/Cutting

Most commercial cannabis growers skip the seed stage and grow new plants from cuttings of established ones, as seeds take longer and are prone to genetic variation, which can affect product quality.

Cuttings are taken from so-called "mother plants" grown for the purpose of genetic cloning. The moniker stems from the fact that they must be female -- male plants produce pollen and seeds but female plants produce the coveted cannabinoid-filled flower.

"Every plant in the greenhouse is a female plant," said Michael Camplin, general manager of CannTrust's Niagara-area cultivation facility. "There are no males allowed in this facility."

Growing a new plant from cuttings produces genetically identical plants, allowing producers to generate cannabis from a certain strain with particular characteristics, he said.

"It's called a mother plant because it's producing basically children," Camplin said. "It's producing young plants that will have the same characteristics as the mother."

2) Seedling

Small cuttings are taken from the mother plants and planted into a moist starter cube in a low light and high humidity environment.

"They're literally babied along," Camplin said.

After two weeks, the roots start to sprout through the starter cube and the seedling is transplanted to a larger cube. After an additional two weeks of growth, the young cannabis plant is moved to a slightly larger base.

3) Vegetative state

Once beyond the seedling stage, the plant enters the vegetative state and is encouraged to grow up and out. This is done by controlling the amount of light the plant receives.

If the plant receives 18 hours of daylight or more in a given day, it will continue to grow without producing any flower, Camplin said.

4) Flowering

Getting the plant to produce flowers involves convincing it that autumn is approaching, which means cutting back on the light cycle.

"Marijuana plants are very light sensitive, and they are triggered to go into flower when the day length shortens in nature, as the summer starts to turn into fall," he said. "The days get shorter, and the plant knows that it's time to reproduce."

Mimicking the change in seasons by shortening the daylight period to 12 hours will prompt the plant to flower and produced the desired bud.

The time needed for a plant to flower depends on the strain, but it can range from as little as seven weeks to as much as 10 weeks, Camplin said.

5) Harvesting

Once the flowering plant has reached the desired stage, it is time to harvest. The plant's flower or bud is coated in tiny, glistening hair-like glands called trichomes that contain the active ingredients in the plant called cannabinoids. The best-known cannabinoids are tetrahydrocannabinol and cannabidiol, known as THC and CBD. Trichomes also contain terpenes, the fragrant oils which produce a unique taste and smell.

The plants are cut and cannabis buds are mechanically separated from the stems and leaves, before being inspected and then trimmed by hand, Camplin said.

6) Drying

The fresh cannabis flower is then dried on racks for up to two weeks. The buds are then stored in loosely closed plastic bags in large bins, which help to control the humidity, for two weeks.

"That equalizes the moisture level, and every day they're opened and stirred -- or burped as they say in the drying room -- and closed back up," Camplin said.

Keeping them in the closed bins also help the buds retain the terpenes, he said.

Once the drying is complete, the bud is graded by size. Larger buds are usually preferred for dried flower sales while smaller buds are often earmarked for oil, he said.

7) Testing and processing

At this stage, the cannabis is tested for quality before it is cleared for the manufacturing process, said Chris Lucky, CannTrust's vice-president of supply chain and manufacturing. On average, it takes 10 to 11 days to get the lab results back.

Once the buds pass the appropriate tests, the pot is then either packaged for sale or put through an extraction process to produce cannabis oil.

8) Extraction

The buds chosen to produce oils are put through an industrial-sized grinder and then baked. Similar to when cannabis is smoked, the heating process activates the ingredients within the bud that provide the medicinal effects, Anna Jakobsmeier, CannTrust's director of extraction and refinement, said.

"We're manipulating it to now provide the medicine," she said.

The baked cannabis is then placed into an extraction machine that uses heated and pressurized carbon dioxide to separate the cannabinoids from the plant.

"You're removing the cannabinoids, as well as some other components of the plant, but you're leaving behind the actual dried product," she said.

The resulting liquid containing the cannabinoids is mixed with a carrier oil known as Medium Chain Triglycerides or MCT oil. The oil is then bottled or put into capsules and packaged for sale.

9) Packaging and Labelling

The finished products are packaged and labelled as per Health Canada's guidelines, which include strict limits on the use of colours, graphics and logos.

Products destined for Canada's adult use market receive an excise stamp, which indicate that the product was produced legally and that applicable duties were paid. Each product must have a stamp corresponding to the province or territory where it will be sold.

Complications with the stamp were blamed by many pot producers for causing a bottleneck in the supply chain, contributing to the shortage. Problems cited by producers included a delay in receiving the stamps, as well as the need for glue to affix the stamps, which slowed down the process.

Cannabis is a brand new industry, and companies are learning and refining the processes as they go, and incorporating automation to speed up the process where possible, Lucky said.

"Everybody is learning the processes... There's a lot of things we have done as an organization, and industry across the board, in terms of how we can automate."

This is a corrected story. An earlier version stated that MCT oil contained coconut oil.