Most seasoned consumers can tell quality cannabis flower by looking at it, but how do cultivators ensure high-quality flower reaches dispensary shelves? The secret is in the way they grow it.
While there are many approaches to cannabis cultivation, it’s always about giving the plant what it needs to thrive. This guide will help you understand the basics of cannabis cultivation and all the love and care that goes into growing the high-quality cannabis flower we carry at High Street.
The basics of cannabis cultivation
Cultivation is a complex practice that combines horticulture and technology in a way that also blends science and art. When cultivating cannabis, the following are among the most important elements to consider.
Growing medium
The medium a cultivator selects for growing a plant is very important. Some may prefer to use soil, where potted plants are rooted in a mix of the cultivator’s choosing. These blends may include soil, peat moss, perlite, and compost, as well as other ingredients. Some cultivators prefer a living soil grow, using soil that contains a rich ecosystem of microorganisms. The precise blend each grower uses can vary considerably.
There are also soilless grows, which include mediums like coco coir or systems like hydroponics and aeroponics. Some cultivators swear by soilless grows as a way to drive higher yields and quality flower through increased control, but they also require much closer attention to detail, especially when it comes to plant nutrition.
Nutrients
Speaking of nutrition, plant growth is supported by a range of nutrients. The most important among these are nitrogen, phosphorus, and potassium, known as “N-P-K” based on their symbols in the Periodic Table of the Elements. Other nutrients, such as calcium and magnesium, are also important for healthy plant growth.
The balance of nutrients a plant needs depends on the stage of its life cycle. For example, plants in the vegetative stage need a lot of nitrogen to promote healthy, leafy growth. In the flowering stage, Nitrogen remains important to support the leafy solar cells of the plant, but it takes a backseat to the now critical phosphorus, which helps drive bud growth.
Grow rooms
Cultivation facilities typically have separate rooms to support plant growth in different stages of the life cycle. This makes it easy to set and monitor conditions room-by-room to ensure each plant has exactly what it needs. It also means cultivators can grow plants at the vegetative stage (called “veg”) at the same time that plants are flowering in the next room. This supports continuous production of flower, rather than periodic harvests punctuated by long stretches of waiting.
Here’s a look at the typical rooms cultivators will maintain:
- Mother room: Some plants are kept in their vegetative state in perpetuity to produce genetic copies known as clones. These plants, known as “mother plants,” are usually isolated from the vegetative and flowering rooms. By maintaining a lengthy lightcycle and vegetative conditions, mother plants continue to produce big, bushy leaves and never begin to flower. Cultivators can take clippings from these mother plants and then root them to produce clones, which are then put through the vegetative and flowering rooms continuously.
- Clone room: Clone rooms are the first stop for cuttings taken from mother plants. This is where they develop their roots and get off to a strong, healthy start. Humidity levels tend to be elevated in these rooms. Once the clones are fully rooted, they are moved into the vegetative room.
- Vegetative room: This is where plants in veg are placed, simulating late spring and early summer conditions. These rooms tend to be more humid than flowering rooms. Lightcycles tend to be longer, usually 18 hours on and 6 hours off, delivering higher levels of blue light to plants.
- Flowering room: Plants begin to flower in late summer and early autumn, when humidity levels begin to drop. As a result, flowering rooms tend to be a bit less humid than vegetative rooms. They also have shorter lightcycles, as the days of late summer and early autumn begin to shorten. Expect 12 hours on and 12 hours off, with higher levels of red light in the spectrum.
Environmental conditions
Controlling the environmental conditions in a cultivation facility is critical. The following environmental factors play a big role in the growth and health of cannabis plants:
- Light cycles: Cannabis is photoperiod-sensitive. This means the plants need specific light/dark periods to trigger vegetative growth (18 hours on, six hours off) or flowering (12 hours on, 12 hours off).
- Light spectrums: Different light wavelengths affect specific aspects of plant development. Blue light promotes vegetative growth, while a red spectrum enhances flowering and bud production.
- Temperature: Cannabis thrives in moderate temperatures (65°F to 80°F). Too hot conditions cause stress and nutrient issues, while too cold temperatures slow growth and may damage plants.
- Humidity: Proper humidity levels prevent mold and mildew during flowering stages, while supporting healthy transpiration (releasing vapor into the air) and water uptake. Humidity levels should generally range from 50% to 70%, on the higher end during vegetative growth and on the lower end during flowering growth.
- CO2 levels: Enhanced CO2 (1,200 to 1,500 ppm) accelerates photosynthesis and can significantly increase growth rates and yields when other conditions are optimized.
- Water quality: Cannabis is sensitive to chlorine, heavy metals, and incorrect pH in water, which can affect nutrient availability and overall plant health.
- Soil pH: The pH level directly determines nutrient availability and uptake, with improper levels leading to nutrient lockout despite their presence. In soil grows, plants in the vegetative cycle often prefer a pH between 6 and 7, while flowering plants typically prefer a range of 6.5 to 7.5.
Training techniques
Did you know plants can be trained? They might not be able to roll over or fetch, but there are a variety of techniques cultivators use to strengthen plants, influence their shape, and increase yields.
These include techniques like low stress training (LST), in which plants are tied down during growth, forcing them to grow in a specific direction to maximize airflow and light exposure. This ultimately results in stronger plants and increased yields.
Similarly, the “Screen of Green” technique is often employed in which plants are made to grow upward through a screen. This is especially effective for large-scale grows, resulting in a flat, even canopy that maximizes light exposure for all the plants, even though they are in close proximity to one another. It can be combined with LST to produce strong, healthy plants with bigger yields.
More intense techniques, such as super cropping, actually focus on damaging the plant in one area to strengthen another area. Super cropping involves pinching and bending branches, simulating predator activity and triggering the plant’s defense mechanisms. This ultimately fuels the plant’s growth during the vegetative stage and produces bigger, denser buds during the flowering stage. Think of it like lifting weights for plants!
The lifecycle of the cannabis plant
The lifecycle of a cannabis plant always follows the same pattern, though the exact timeline varies by strain. The lifecycle described below is for a female cannabis plant, which is the sex that produces cannabis flower. Male cannabis plants are generally identified early on and culled before entering the grow room.
Below, we’ve provided rough estimates for how long each stage of growth lasts, as well as a range of suitable temperature and humidity conditions for the plant at each stage.
Germination
- Duration: 3 to 10 days
- Photoperiod: Complete darkness
The germination stage is when the taproot first emerges from the cannabis seed. The right combination of moisture, oxygen, temperature, and light is necessary for a seed to germinate.
In nature, seeds lay dormant in the soil throughout winter until warmer spring weather comes. Once it warms up, taproots emerge and anchor the plant in the ground, forming the foundation from which the root network will spread. In cultivation facilities, seeds are germinated by creating these conditions, no matter the time of year.
Seedling
- Duration: 2 to 3 weeks
- Photoperiod: 18 hours of light, 6 hours of darkness
Once a germinated seed has taken root, a stem will break through the soil and sprout two leaves, known as cotyledon leaves. At this point, the plant is officially a seedling, a baby cannabis plant that is just setting out on its life journey.
Seedlings remain very fragile and need the ideal temperature and humidity to flourish. It’s at this point that the plant needs light as well — at least six hours, though it’s common to expose them to an 18/6 photoperiod at this time. Seedlings do not yet need nutrients, as all the nourishment they’ll need so far should be present in the seed itself.
Vegetative
- Duration: 2 to 8 weeks
- Photoperiod: 18 hours of light, 6 hours of darkness
Once the seedling sprouts its first node, where the first branches emerge from the stem, it has entered the vegetative stage. Over the coming weeks, the plant will rapidly grow and produce new leaves. Nitrogen fuels vegetative growth, and the plant will need plenty of it.
Conditions should reflect the dog days of summer: long photoperiods, high temperatures, and relatively high levels of humidity. At this point, the root network is still forming, spreading out in search of nutrients and moisture. During the vegetative stage, the plant is youthful and vigorous, and it’s a prime opportunity to expose it to stress training.
Flowering
- Duration: 6 to 12 weeks
- Photoperiod: 12 hours of light, 12 hours of darkness
As the summer season comes to an end, temperatures become somewhat more mild and humidity drops. This is when plants begin to flower. They do so in preparation to drop their seeds before winter comes, paving the way for the next generation once spring comes again.
Late summer and early autumn are the time, then, when plants grow big buds in the hopes that male plants pollinate them to produce seeds. Of course, in a cultivation facility, male plants have been removed, so cultivators aim to maximize bud production during this period.
Photoperiods decrease during flowering, simulating shorter days. Phosphorus becomes increasingly important in plant nutrition to support the growth of healthy buds. This period tends to last a long time. The fast times of a plant’s youth are in the past; in midlife, cannabis plants prefer more stable, mild conditions. Cultivators tend to ease off stress training and focus on supporting bud production.
Harvesting, drying, and curing cannabis plants
Harvesting cannabis at the right time is crucial for maximizing potency and quality. The optimal harvest window typically occurs when trichomes, or resin glands, turn from clear to cloudy with some amber coloration. This is usually seven to nine weeks into flowering for most strains. Growers should look for additional signs, like pistil darkening, leaf yellowing, and slight curling of fan leaves, as cues that the plant is ready for harvest.
Harvesting too early results in less potent buds with underdeveloped cannabinoid profiles. Taking down the plants too late can create an overly sedative effect as delta-9 Tetrahydrocannabinol (THC) degrades to Cannabinol (CBN).
The drying process is equally important to the growing phase and significantly impacts the final product. After harvesting, plants should be hung upside down in a dark room with controlled temperature (60°F to 70°F) and humidity (45% to 55%) with gentle air circulation for up to two weeks. This slow drying preserves terpenes and cannabinoids while removing moisture.
Once stems snap rather than bend, buds should be trimmed and transferred to airtight glass jars for curing. During the first two weeks of curing, jars should be “burped” daily by opening them briefly to release moisture and replenish oxygen. A proper cure, lasting anywhere from two weeks to several months, improves flavor, smoothness, potency, and shelf life by allowing chlorophyll to break down while preserving the plant’s desirable compounds.
Shop High Street for top quality flower
Now that you have a sense of just how much effort goes into producing great cannabis flower, why not pick some up? Swing by High Street Dispensary in Hackettstown, NJ to shop some of the Garden State’s finest cannabis products. Even if flower isn’t your go-to product, meticulously cultivated cannabis goes into everything we carry. Ask our friendly budtenders which product might be best for your needs, and we’ll help you make sure you go home with something that’s perfect for you.