Here is the full list of all 75 Idle magic herb achievements.
19 spell level 100
30 monster 1000
18 spell level 100
29 monster 1000
level 19
28 monster 1000
level 18
Level 5 fairy grass
All fairy grass
Level 4 fairy grass
40 culture pots
27 monster 1000
26 monster 1000
25 monster 1000
24 monster 1000
23 monster 1000
22 monster 1000
17 spell level 100
21 monster 1000
20 monster 1000
level 17
19 monster 1000
16 spell level 100
15 spell level 100
18 monster 1000
14 spell level 100
13 spell level 100
16 monster 1000
17 monster 1000
12 spell level 100
11 spell level 100
level 16
15 monster 1000
10 spell level 100
14 monster 1000
09 spell level 100
level 15
13 monster 1000
08 spell level 100
level 14
07 spell level 100
06 spell level 100
12 monster 1000
11 monster 1000
05 spell level 100
10 monster 1000
Level 3 fairy grass
04 spell level 100
Level 2 fairy grass
level 13
09 monster 1000
03 spell level 100
08 monster 1000
07 monster 1000
02 spell level 100
06 monster 1000
level 12
level 11
05 monster 1000
level 10
01 spell level 100
04 monster 1000
level 09
03 monster 1000
level 08
02 monster 1000
level 07
level 06
01 monster 1000
Level 1 fairy grass
level 05
level 04
level 03
level 02
level 01