Cannabis is an annual plant. A single season completes a generation and although plants may continue to grow during successive years, all future hope lies in the seeds grown from the first year's pollination.

Marijuana plants may belong to one of many different varieties which follow somewhat different growth patterns. The following section describes and outlines the more common stages of growth.


With the coldness of winter over, the warmth of spring starts to stir activity in the embryo of the seed. Water is absorbed and the embryo's tissues swell and grow, splitting the seed along it's edge. The embryonic root appears first and once clear of the seed, begins it's downward growth in response to gravity.

Meanwhile, the seed is being lifted upwards by the growing cells which forms the seedling's stem. Now anchored by the roots and receiving water and nutrients, the embyonic leaves (cotlydons) unfold. They are a pair of small, somewhat oval, simple leaves, now green with chlorophyll to absorb the life-giving light. The process of germination is usually complete in three to ten days.


The formation of the second pair of leaves begins the seedling stage. They are set opposite each other and usually have a single blade. They differ from the embryonic leaves by their larger size, spearhead shape and serrated margins. With the appearance of the next pair of leaves, each leaf usually has three blades and is larger still.

A basic pattern has been set. Each new set of leaves will be larger, with a higher number of leaves per blade until, depending on variety, they reach their maximum number. This is usually seven leaves per blade, but may be as many as nine or eleven leaves. The seedling stage is complete when the plant has reached this maximum leaves per blade, usually within four to six weeks.

Vegetative Growth:

This is the period of maximum growth. The plant can grow no faster than the rate that it's leaves can produce the energy required for new growth. Each day, more leaf tissue is created, thereby increasing the plant's capacity for growth. With excellent growing conditions, Cannabis is known to grow as much as six inches a day, although the rate is more commonly one to two inches.

The number of blades on each leaf begins to decline towards the middle of the vegetative growth stage. Then the arrangement of leaves on the stem (phyllotaxy) changes from the usual opposite to alternate. The internodes (stem spaces between sets of leaves, which had been increasing in length) begins to decrease, and the growth appears to be thicker. The vegetative stage is usually completed in the third to fifth month of growth.


This is a quiet period of one to two weeks during which growth slows considerably. The plant is beginning a new program of growth as encoded in its genes. The old system is turned off and the new program begins with the appearance of the first flowers.


Cannabis is dioecious and each plant produces either male or female flowers and is considered either a male or female plant.

Male plants usually start to flower about one month before the females. First the upper internodes elongate and in a few days the male flowers start appearing. The male flowers are quite small (about 5mm) and are pale green, yellow, or red/purple in colour. They develop in dense, drooping clusters (cymes) capable of releasing clouds of pollen dust. Once pollen falls, the males lose vigour and soon begin to die.

The female flower consists of two small (5 to 10mm long), fuzzy white stigmas, raised in a "V" sign and attached at the base to an ovule which is formed from modified leaves (bracts and bracteoles), which envelop the developing seed. The female flowers develop tightly together to form dense clusters (racemes) or buds, heads, cones or colas. The bloom continues until the pollen reaches the flowers, fertilizing them and beginning the formation of seeds. Flowering usually lasts about one to two months, but may continue for longer when the plants are not pollinated and the climate is still mild enough.

Seed Set:

A fertilized female flower develops a single seed, wrapped in bracts. In thick clusters, they form the seed-filled buds that make up most fine imported marijuana. After pollination, mature viable seeds take from ten days to