The marijuana plant grows in three main stages: germination, vegetative growth, and flowering. There are also three additional sub-stages in the marijuana plant's life cycle. Here we describe the complete life cycle of the cannabis plant in brief.
Germination
Germination is the initial stage of growth and occurs when the seed's embryo breaks through the shell, the testa, and the seedling produces its first initial root, the plumule. This root fixes itself into the germination medium and pushes the newborn seedling up and over the surface. Following surface contact, two embryonic leaves, the cotyledons, open outward to receive sunlight, pushing the empty testa away from the seedling. It takes anywhere between 12 hours and 7 days for seeds to germinate. Sometimes the shell can be removed by hand if it appears to be obstructing the seedling's growth. In nature the wind helps to shake the seed shell away. Since artificial wind is not initially used in the germination environment, some seedlings find it harder to shed their shell, although most do not have a problem doing so. Care should be taken not to damage the seedling when removing the shell.
Seedling
After the first pair of embryonic leaves receives light, the plant will begin to produce another small set of new leaves. These leaves are different from the first two and may have some more noticeable marijuana characteristics, such as the threerounded, finger-shaped points. As the seedling grows, more of these leaves are formed and bush upward along with the stem. Some stems are very weak at this sub-stage and need the support of a small, thin wooden stake tied to the seedling with some fine thread. The seedling substage can last between one and three weeks. At the end of the seedling substage, your plant will have between four and eight new leaves while some of the original bottom leaves and cotyledons may have dropped off.
Vegetative Growth
The plant now begins to grow at the rate that its leaves can produce energy. At this stage the plant needs all the light and food it can use. It will continue to grow upward and produce new leaves. It will also develop a thicker stem and thicker branches, as well as its maximum finger (blades) numbers on the leaves. As long as plenty of sufficient light, nutrients, CO2, water and other optimal environmental conditions are met you can expect your plant to grow from 1/2 - 2 inches per day! This is also the stage in which the plant's root system strengthens and matures. Your plant begin to look like a real marijuana plant! This is the stage where this happens. Then it is time for the plant to enter pre-flowering. The vegetative growth stage can last between one and five months.
Pre-flowering
At this sub-stage, the plant's upward growth slows. Instead of growing taller, the plant starts to produce more branches and nodes. The plant fills out during this stage and will start to show a calyx where the branches meet the stem (nodes). This calyx is the ultimate indicator that the plant is in the pre-flowering phase of growth and is mature enough to flower. Preflowering can last anywhere from one day to two weeks. During this substage, plants start to exhibit signs of their sex and more calyx development takes place at other node points.
Flowering
Here, the plant continues to fill out. The plant's sex is now clearly evident. The male plant produces tiny, creamy, yellow sphere shapes that are clustered together like grapes. The female plant produces little white pistils that look like oily tentacles coming out of a pod. Each of the plants will continue to fill out and their flowers will continue to grow. It can take between 4 and 6 weeks for the plant to fully develop its flowers, depending on the strain. During this time the male's pollen sacks would have burst, spreading pollen to the female flowers.
Seed Production
The female plant will produce seeds at this point if she has received viable pollen from a male plant. The seeds grow within the female bud and can take anywhere between 2 and 16 weeks to grow to full maturity. The female pistils may change color before finally bursting the seedpods, sending them to the soil below. Breeders like to collect seeds before the seedpods burst.
If, during the flowering stage, there are no males present to pollinate the female plants, the buds will grow larger and develop more resin glands. Resin may drop down on to the leaves, making the plant very sticky. The pistils on the buds will begin to thicken and cluster. The reason for the high increase in bud growth is that the female plant is trying her best to attract male pollen. This is the sinsemilla condition. Toward the last days of flowering, the pistils may change color, indicating that the plant is ready for harvest.
Cycle Times
Given different breeds and the various stages of growth, it can take between 10 and 36 weeks for a plant to grow from a seed to full maturity. The most common grow time is three to four months. All this is dependent upon the strain that you have selected. Pure Sativa can run anywhere into the six to nine month bracket. Indica can flower in six weeks. As you can image, a Sativa/Indica hybrid plant will fall into the two to four month flowering period.