When your plant becomes a seedling (2-3 weeks), you’ll notice it developing more of the traditional cannabis fan leaves. As a sprout, the seed will initially produce leaves with only one ridged blade. Once new growth develops, the leaves will develop more blades (3, 5, 7, etc.). A mature cannabis plant will have between 5 or 7 blades per leaf, but some plants may have more. Cannabis plants are considered seedlings until they begin to develop leaves with the full number of blades on new fan leaves. A healthy seedling should be a vibrant green color.
Be very careful to not overwater the plant in its seedling stage—its roots are so small, it doesn’t need a lot of water to thrive.
At this stage, the plant is vulnerable to disease and mold. Keep its environment clean and monitor excess moisture. Be sure to give it plenty of light.
Even if growing outdoors, a lot of growers will start their seeds inside under an artificial light to help them through this delicate stage.