At the end of your turn, if you have fulfilled the requirements of a Goal card that is still in the middle of the table, you can claim the corresponding Goal tile, see Goals. When you claim a Goal, take the matching tile and immediately place it in your pond following the directions on the card. You cannot claim the same Goal more than once (exception: Path).
If you take the last available tile for a Goal, no player will be able to claim that Goal again.
Example: Having upgraded his second foliage tile with a water-lily A, William has fulfilled the Purple Water-Lily Goal card’s requirements (having an empty water hex and 2 adjacent water-lilies in his pond).
At the end of his turn, he takes the purple water-lily Goal tile and places it in the pond B as indicated on the Goal card (the purple water-lily must be placed on an empty water hex.)