Level 3 in Fairyland on Facebook allows than more types of spells and has a more demanding set of requirements than level 2.

Progress to level 4 requires the harvesting of

5 or more different colours of Bellis Lycaena (including those already grown),
3 or more different notes of Carmena Uniflora (including those already grown), and
1 or more Rosa Amora.

You can also plant a Cumulus Albiflorus, Nestflower Herb, Thornbloom Herb, Sundragon Herb and Fructus Randomus.

The Fructus Randomus can be grown for fun and for attracting a Tortoise, but if there is a flowering Bellis Lycaena the Tortoise is unlikely to visit.

The Thornbloom Herb is still one of the best because the bunny it attracts is worth four diamonds. Some players keep a Thornbloom until level 13 or later.