The radicle is the embryonic root. It is the first organ to break out of the seed coat during germination, and it grows straight down under gravity to become the primary root (the taproot). Root hairs form just behind its tip within a day or two.
In practice
When growers say a seed has "popped" or "tailed", they mean the radicle is out. Plant it once it is about 5-20 mm (0.2-0.8 in) long, tip down, roughly 5-10 mm deep. Longer tails are fragile and easily snapped; a broken radicle tip often stops or badly delays the seedling. Handle by the shell, never the root.
The radicle and its fine root hairs dry out in minutes in open air. Move quickly from paper towel or water to medium, and keep the medium moist, not waterlogged.
Don't confuse with
- Taproot: the mature primary root that the radicle becomes.
- Hypocotyl: the shoot-side stem segment that lifts the cotyledons; it emerges after the radicle.
- Root hairs: tiny single-cell outgrowths on the radicle, not separate roots.
The protective outer layer of a seed; in cannabis it is fused to the fruit wall and forms the hard shell that cracks open at germination.Germination is the stage where a viable seed absorbs water, splits its shell and pushes out a root (radicle), usually within 1-7 days at 20-30 °C.The dominant primary root that grows straight down from the radicle of a seed-grown plant, with lateral roots branching from it.A microscopic tube-like outgrowth of a single root epidermal cell near the root tip that greatly increases surface area for water and nutrient uptake.A seedling is a young cannabis plant from emergence of the cotyledons until it has several sets of true leaves, typically the first 2-3 weeks.Overwatering is watering so often that the medium stays saturated, starving roots of oxygen, which causes drooping, slow growth and root disease.The section of seedling stem between the root and the cotyledons; it elongates to lift the seed leaves above the medium.One of the two rounded seed leaves packed in the embryo that open first after germination and feed the seedling until the true leaves take over.
