Cannabis plants, like all living things, go through a series of stages as they grow and mature. If you are interested in cultivating cannabis, it is especially important to understand the changes a plant undergoes during its life cycle, as each stage of growth requires different care.
The vegetative phase is a vital period in the life cycle of a cannabis plant. Growers need to provide optimal environmental conditions for their plants to grow as large and healthy as possible. Size often equates to yield. The bigger plants become, the more nodes or “bud sites” they develop, and the more flowers they will be able to produce. But size is not the only factor.
Cannabis life cycles
Generally speaking, it takes anywhere from 14-32 weeks, or about 4-8 months, to grow a weed plant.
The biggest variability in how long a cannabis plant takes to grow will happen in the vegetative cycle. If you are growing indoors, you can force it to flower after only a few weeks when it is small, or after several weeks when it is big. If you are growing outdoors, you are at the whim of the seasons and will have to wait until fall to harvest. The plant will develop buds in the last 8-11 weeks.
The life cycle of cannabis can be broken down into four primary stages from seed to harvest:
- Germination (5-10 days)
- Seedling (2-3 weeks)
- Vegetative (3-16 weeks)
- Flowering (8-11 weeks)
What is the vegetative stage?
The vegetative phase is a period of the growing cycle that takes place after seedling and before flowering.
After your cannabis seeds germinate, they will emerge from the soil as seedlings. These youngsters feature a short stem and two rounded cotyledons (first leaves produced). Eventually, the first “true” leaves will form. Over the subsequent 2-3 weeks, seedlings will start to mature and produce a large number of fan leaves (structures required for photosynthesis). This marks the beginning of the vegetative phase.
The vegetative phase can last anywhere between 3-16 weeks (or longer), depending on the genetics of a cultivar and the goals of the grower. Explosive growth occurs during this time.
Plants are typically transplanted into larger containers at the start of the vegetative phase to give their root system more room to expand. The main stem will ascend, and the space between nodes will increase dramatically. Indica cultivars will remain short and put out lots of lateral growth, whereas sativa varieties grow taller with much less ramification. For photoperiod varieties, the vegetative phase ends when the light cycle shortens.
What is the best amount of time for a plant to be in veg?
There is no ideal amount of time to keep your plants in their vegetative stage. You decide for yourself how long you want to take to build leaves and branches of your plant while it gets 18-20 hours of light, and then induce flowering using 12 hours of light and 12 hours of darkness. The longer you keep your plants in the vegetative stage, the bigger your plant will be, resulting in bigger yields.
The drawback to a longer vegetative period is the fact that it takes more time, lengthening your growing schedule and allowing more time for things to go wrong along the way. Vegging a plant for three months is a waste of time; think of it as something with diminishing returns when you overdo it.
Some growers prefer to keep their plants small while still achieving excellent yields, which can be done by training plants. These techniques need to be implemented in the vegetative stage before the first flowers begin to emerge. Many essential physiological functions are underway during the vegetative stage.
Fan leaves are working hard to convert light and carbon dioxide into energy. The root system is expanding and providing a firm anchor to prevent the plant from toppling over; the roots also work to uptake vital nutrients and water. To meet the demands of plants during this time, growers need to ensure they provide the correct amount of light, water, and nutrients.
When it is still young, your plant will need water close to the stalk, but as it grows the roots will also grow outward, so start watering further away from the stalk in the soil so roots can stretch out and absorb water more efficiently.
Cultivators also need to be aware of pests and pathogens and do their best to prevent these threats from damaging or even killing their crop. Ultimately, the vegetative period sets the stage for flowering. The healthier plants are during this time, the more prepared they will be for flowering a bountiful harvest.
Determining the sex of your plants
If you need to determine the sex of your plants (to discard the males), they will start showing sex organs a few weeks into the veg stage. It is imperative to separate males so they do not pollinate the females. There are two commonly utilized methods of determining gender in cannabis plants.
The first method for determining gender is to carefully examine the 5th series of leaves on your plant. You will want to do this right before the plant should flower. Indicas and hybrids with indica genetics will display their sex between the leaves of the plant right before they flower.
If you look very carefully, you should be able to see a tiny white fiber if the plant is female. If the plant is male, it will have a small ball instead of a fiber or tendril. This method is simple, but it is not the most reliable, and sometimes it is very difficult to find the developed sex organs on the plant because they are so small. A magnifying glass may be helpful to distinguish the difference.
Another method is to take cuttings. Once your plant is in the vegetative stage, you can take cuttings from the plant and root them in another room (best done indoors). Expose the newly rooted cuttings to 12 hours cycles of light and darkness. The plants should flower within several days. If any of them are male, you will want to remove them from the grow room.