Sales Hotline +1 (855) 904-4090
Great! 4310 Reviews on
  • Buy Cannabis Seeds Online!
  • Secure Payment
  • Discreet Packaging
  • High Quality Seeds for Sale

The Cannabis Vegetative Stage

Apr 13, 2020
Cannabis World

A Guide to the Cannabis Vegetative Stage

Cannabis plants go through several life stages, with the vegetative stage being one of the most crucial. This phase occurs after seed germination and before bud development. After the seeds germinate, they emerge as seedlings with short stems and round cotyledons.

Over the following two to three weeks, seedlings mature and begin to produce the fan leaves necessary for photosynthesis. This leaf growth signals the start of the vegetative stage. This phase may last from 3 to 16 weeks, depending on the grower’s goals and the strain chosen. For instance, Indica-dominant strains remain relatively short with significant lateral growth, while Sativa marijuana seeds grow taller and narrower.

When Does the Vegetative Stage End?

In photoperiod varieties, the vegetative stage ends when the light cycle is shortened.

  • In outdoor gardens, it happens when the season changes from summer to fall.
  • For indoor crops, lighting schedules are often shortened in efforts to force photoperiod strains to flower. Plants move from the vegetative stage to the flowering phase when they get 12 hours of light and 12 hours of darkness.

By comparison, auto-flowering strains initiate the flowering stage based on age rather than lighting. Wedding cake seed, for example, is available in both auto-flowering and non-auto versions from our website.

Why the Vegetative Phase is So Important

Vegetation is one of the most important phases in the cannabis life cycle. Growers must provide the right conditions for plants to grow as big and healthy as possible. As in many other crops, there’s a correlation between plant size and yield. The bigger a plant grows, the more bud sites it will have, and the more flowers it will grow. However, size is only part of the equation.

Some cannabis growers prefer to keep plants small without sacrificing yields, which is accomplished through various training methods. These strategies must be implemented during the vegetative stage before flowers emerge.

Many of a plant’s key physiological functions begin during this stage of life. Fan leaves convert carbon dioxide and light into energy. Root systems expand and provide a firm foundation for plant growth while absorbing water and vital nutrients. To meet a plant’s demands during this important time, growers must take steps to provide the right amount of nutrients, water, and light.

Cannabis growers must learn about pathogens and pests so they can prevent such threats from killing and damaging their crops. The vegetative phase sets the tone for the flowering stage. The healthier your plants are during vegetation, the more ready they’ll be for flowering and harvest.

Achieving Good Vegetative Growth

The above factors apply to all cannabis grow ops. When a grower successfully balances these variables, remarkable vegetative growth becomes possible. Though the plant’s needs remain largely the same, growers should know the differences between outdoor and indoor growth. These radically different environments present cultivators and crops with unique challenges.

  • In indoor gardens, plants are usually grown in tents or dedicated rooms. This practice comes with certain benefits and drawbacks. An indoor grower retains control over the growth environment during the entire growing cycle. During vegetation, they can run lights 24 hours per day. The more exposure plants get, the faster photosynthesis and vegetative growth occur.

With greater control comes more responsibility. An indoor cannabis cultivator must measure the room’s temperature, humidity, and CO2 level regularly for optimal plant growth. Growers may have to buy hygrometers, intake fans, dehumidifiers/humidifiers, and extractor fans to keep things running smoothly. Though these systems can be automated with sensors and timers, such tools can be expensive for first-time growers.

  • In outdoor gardens, growers have less control over their plants’ growing cycle. They’re at the mercy of the elements, which may be beneficial in certain cases. For starters, there’s no need to provide lighting, and irrigation and rain eliminate the need for regular watering. To achieve good outdoor vegetative growth, you’ll need to boost the plants’ defenses. Small creatures eat leaves and roots, while larger animals can cause serious damage to plant stems. Companion plants, biological controls, fencing, and netting provide the first line of defense against animal intrusion. To minimize the risk of mold contamination, use foliar sprays and plant crops in areas with plentiful airflow.

Giving Your Seeds the Start They Need

As previously discussed, cannabis plants go through the seedling stage before entering the vegetative phase. It’s a crucial time in the plants’ life cycle. Just as effective vegetative growth lays the foundation for an ideal flowering phase, healthy seedlings provide a firm foundation for the rest of the growth cycle. In the sections below, we will review some of the most crucial factors to consider during the seedling stage.

The Growth Medium

Cannabis cultivators have several options, including water (hydroponics) and soil. The growth medium offers room for roots to grow, and in soil-based gardens, it provides vital organic matter. Beneficial microorganisms like mycorrhizal fungi form symbiotic relationships with cannabis plants. They assist in the degradation of organic material and the absorption of nutrients. In hydroponic gardens, begin with filtered water. Tap water won’t help, as it’s full of chlorine and other harmful substances.


Light is an essential factor in cannabis cultivation. Along with carbon dioxide and water, it’s a key player in the photosynthetic process. Start with quality grow lights so your plants grow strong and healthy. LED lights are suggested because of their reduced heat emission and lower operational cost.

As we mentioned earlier in our guide, indoor photoperiod cannabis strains thrive with 18-24 hours of lighting each day. The more lighting plants get, the faster they grow. Most growers allow their plants to vegetate for four to eight weeks, after which time a 12/12 lighting schedule is needed to kickstart the flowering phase. As the name implies, auto-flowering plants will flower of their own accord. Give them 18 to 24 hours of lighting per day during the vegetative and flowering stages.


Marijuana plants have certain nutritional requirements, and those needs vary during vegetation and flowering. In the vegetative phase, plants need more nitrogen to grow healthy leaves and stems. They also need plenty of potassium for the proper closing and opening of stomata and to create energy. Vegging plants also need magnesium for photosynthesis and calcium for better cell wall health.

Growers can buy special vegging nutrient formulas to simplify the process. These products are widely available online and they offer all the nutrients cannabis plants need during the vegetative phase. In hydroponic gardens, growers should buy special nutrients and use them as directed on the label.


All living things need water, and cannabis plants are no exception. Plants need water to absorb nutrients in hydroponic and soil grow ops. During transpiration, water moves up the plant’s stem to its leaves, carrying nutrients where they’re needed most. However, over-watering is just as risky as under-watering. It can deprive the roots of oxygen and lead to root rot. When watering vegging plants, let the top inch of soil dry out before adding more water. Hydro-grown plants get their water from the growth medium, so supplemental watering is not necessary.


Vegetative cannabis plants do best in temperatures between 20 and 30 degrees Celsius. Thankfully for outdoor and indoor growers, this is quite a wide range. Vegging plants can live in high humidity but try not to let the level drop below 40%. Humidity and temperature can easily be measured with a hygrometer and a thermometer. While indoor growers can manipulate these two factors with humidifiers, dehumidifiers, and AC units, outdoor cultivators can put up sun shelters for vegging plants.


Proper airflow is essential to good plant health. In grow tents, input and exhaust fans will help keep the air fresh. These fans pull in carbon dioxide and remove extra oxygen. Good airflow also prevents mold formation.

During the First Part of the Vegetative Stage

Plants grow quite rapidly during the first two weeks of the vegetative phase, and growers should continuously monitor them and make changes accordingly. Because the plants grow so fast, it may be necessary to change the position of the grow lights.


Every plant should have enough space, as crowded cannabis plants will end up overshadowing one another. Though a strain’s genotype determines how tall it grows, plants can be manipulated with various training methods. Growers can plan their operations by calculating how many plants they can grow per square foot of growing space.


This is a proven way to control plants’ height while increasing potential yields. By cutting the top of a plant’s main stem, a cultivator can encourage lateral (side to side) growth, which enhances yield. Topping can be done when a plant has developed three to five nodes. This technique should only be used during the vegetative phase.

Begin with a sterile pair of shears and cut the plant at the tip of its main stem, which will lead to divergence. Repeat the process to produce more flowering sites but be sure to give the plant time to recover after each topping. Every time a plant is topped, the vegetative phase is extended.

Closing Thoughts

Each phase in a cannabis plant’s life is important, but the vegetative stage is crucial to overall health and growth. What you do during vegging may make the difference between a great yield and a poor one. Remember that when you are researching where to order marijuana seeds, the best yields start with the best seeds, and you can find a wide selection of these at We offer the option to purchase each strain by the single seed, but we also offer wholesale marijuana seeds.

Popular Posts
Check All Popular Posts

Buy Fast Vegging Weed Seeds

Growing vegetative stage marijuana

Related Posts

Ultimate Guide to Marijuana Legalization Within the US

Ultimate Guide to Marijuana Legalization Within the US Intro to Marijuana Legalization Within the US Marijuana was once legal in the US. In ...

What Do Marijuana Plants Need

What Do Marijuana Plants Need What Do Marijuana Plants Need? Those who are interested in growing marijuana should learn what this plant need...

What Is Live Resin

What is Live Resin     Live Resin Cannabis Concentrates-What Are They and How Do They Work? Technological advancements benefit eve...