Problem: herb seeds are super rare. That makes Gardening very, very difficult to put to good use. Currently, the only benefit from having Gardening, instead of just having a lot of holy water, is being able to convert a non-herb level into an herb-sustaining level. (And, obviously, saving yourself some holy water.) In order to achieve this benefit, you must have an herb seed, which is very rare.

Suggestion: alter the Gardening skill so that when Used on a square containing an herb bush, it lowers the size of the bush (in exactly the same way that picking herbs does, i.e., according to the Herbalism skill), and generates herb seeds (but no herbs). Perhaps 1d3-1. Better yet, some formula based on the Gardening skill value.

Benefits: characters who acquire Gardening will have an easier time of creating gardens. Creating gardens is already easy enough even for those without Herbalism or Gardening, so this will not be an overpowering change.

P.S.: It's also possible, that there is a means of acquiring herb seeds somehow, that I am not aware of, which would obviate this suggestion entirely. Before anyone replies "kill things in the ID," that is not a means of acquiring any particular item, it can only generate random drops. In any case, that is likely to generate more than 3x as much holy water as herb seeds, given their relative rarity.