There is still more to prove. China must show that the plants can continue to grow, and it is not a means between the very varying temperatures and the lower gravity. The lander must make dramatic changes to maintain the conditions of the biosphere and keep its interior relatively consistent.
Even with these challenges, this is an important milestone: it suggests that astronauts will have a realistic chance of growing plants on missions to be used for food, oil and other resources. It could ease the freight load for long-term missions to the Moon and Mars, and it could allow to remain after some utilities are low. Foreign agriculture is far away, but they are at least on the horizon after this achievement.
15. January 2019