What are you talking about? Farmer is one of the easiest credo to do.
If you want it to be faster, just plan ahead and plant more crops.
Have big fields for every one of them, u don't even need to take care of it, just have it sitting there. When u get the quest "harvest 100 wheat" you'll already have the field ready, and can do it in a second.
Take quarryman as an example. Same tier, much harder quests. You are asked to get to lower cave levels, which can't just be done by waiting a day or two. You're asked to mine stones and ores that you might not have in your cave, and have no clue where to find. Or to chip a boulder of a miner that is nowhere on your continent.
I'd rather have to way a couple of days and be able to complete my quest, rather than being forced to abandon two quests in a row because they require me to chip marble or mine cinnabar.
If you have spent over a month on farmer credo, and it's only your second credo, you're doing something wrong. Like probably having super small fields, or not using all crops.
The only crop that can stop you in your tracks are pumpkins, which so far I haven't seen in a credo quest, luckily.
I'm doing the farmer credo too, after doing 3 other, and I don't see an issue with it. If I wanted to, I could have spent the last month preparing for it, by planting EVERYTHING I could and make some large fields, and then be done with it in just a couple of days.