Castaway Paradise

This will be the trophy that you need to invest the most time into due to the level needed. There are 40 flower total to grow, the last of which is the Yellow Hyacinth that unlocks at level 34. The full list is as follows:

Since there is no sale value for the flowers, it's recommended you wait until you have all the flowers available to purchase in the store and then plant them all in one go. This assures you are not missing any and you won't really have to keep track of anything. Just mind the flowers with multiple color options and make sure each one listed in the spoiler above is accounted for.

The Lily takes the longest to grow (12 minutes) so if you do them altogether, that's how long it will be before the trophy unlocks.

To get to level 34 as quickly as possible, it's recommended that when you open up the Western Island, you grow tomato plants in both farming sections over and over and over again. Each tomato plant will grant you 24 XP every 16 minutes and with 24 plots, you're looking at about 576 XP gained. Doing this along side quests will speed the process up versus if you were going for quests alone.