Once you have your Platypus, you will see small things that look like blue campfires on the ground every now and then. These are Chalices but you need to use the Platypus to carry a Wakfu Gel to the Chalice to make it grow into a Manolia. Repeat this 10 times for the achievement.
(It doesn't matter if you kill the Manolia or collect its honey, all the matters is that you grew the Manolia)