Globe artichokes can be grown quite easily from seed but it's even easier to simply divide the pups when they emerge and replant them for the new season. Sometimes one plant will produce several pups (off-shoots) from the base which can be sliced off and dug out with a nice sharp spade. Then it's just a matter of replanting and keeping the water up until the new baby plant has a stable root system. I've seen where the mother plant does off completely without any pups only for a new plant to regrow in the same spot several weeks later so perhaps there can be a dormant stage before reshooting in some cases. I have also seen pups grow from the stem of the plant several inches from the soil and cutting the stem under these new pups (shoots) then replanting the stem piece with the pups attached can produce new plants - strange Once established, artichoke plants are pretty hardy (like any thistle) and are best not overwatered but they can withstand slightly heavy soils from what I have seen. The artichoke is a pretty big plant and need about 40-50 cms space between each other and they can get to about 1/2 metre tall (and higher when producing buds).