Dandelion's tap root may grow fat, and reach as deep as 1.5 ft (45.7 cm) in loose soil. The root has numerous hairy rootlets. Dandelion is a hardy herb and will regrow from root parts left in the ground during harvest.
They draw water and norishment up from the soil.
plants grow into maturity intill about 2-3 weeks.
a good rule of thumb for any plant not just marijuana is that the roots are the same size as the plant that is sticking out of the ground
to keep them planted in the ground and to suck up water and to make there own food
i think tomato plant and ginger plant..........just to be sure research it....
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