You could, but you may not need to. Depending on the skill level of the artist, you may be able to have them take over cooking too. Or the angler could also be the gardener, again depending on the skill level.
If you have the sims3 store content of the Multi-Tab, your angler or artist could actually learn both cooking and gardening from the tablet.
If you have University, the brain machine 2.0 (I don't recall the name offhand) has an option for brain enhancement in which it can up a skill level (or, possibly, give you the singed moodlet instead), and is on a cooldown, but it's something you might have your angler do in the morning before his daily dose of fishing, then do again in the evening just before going to bed.
Or, make the cook be the gardener.
Or, give one of those to the founder, if they aren't going to be supermaxed skills.