How do you get more seeds to enter the Sakura room

I have run out of seeds that are required to enter the Sakura room. I have a quest to complete. I know that you can sometimes get them when banishing Joe the Farmer. But this is taking a long time, and is hit and miss. Is there any other way?
Thanks,
Sherry

Yes, you can charge certain collection for seeds

Open detective chest that contains room keys for all room except crypt or bunker

You get detective chest generally when you reach stage 4 of different achievements

Note: I try to save these chest to get keys for island, brig and UFO because keys are harder to get than seeds

Good luck

I would advise you to banish only when you have a turtle of luck running (or wait until you get one). Otherwise the seeds drop sometimes with Joe, but with the turtle they drop allways I think.
I almost never banish any creature without a turtle running.
Also with that turtle of luck the seeds drop more often in the other rooms (I think hunting. library).
Detective chest is the best option to get keys for the rooms, but it's a long way sometimes to arrive at the achievements to get to those...