I consider this slightly odd, because I've never been this lucky before. I'm sharing it in-case it's of use to anyone else.
In Moonlight Falls, there's a 2 bed, 1 bath house called 204 Lakeside Drive. If you can afford it,
buy it!Apparently there's 1-2 common insect spawners near it (got 2 butterflies so far, and glowbugs are out at night), 1 common gem spawner (got ruby and smoky quartz from it) and a special seed spawner (got 3 specials and 1 rare over 2 days!) all right next to the lot! You're also right next to the lake for easy fishing.
I don't think I've ever been this lucky in the game... I'm wondering what the catch is...
EDIT: Grabbed some screenshots to show just how close the spawners are to the house.
This seems to be common gem...
...and common insect...
...and this big patch of grass is where the seeds spawn. At the top, you can see some butterflies. There's 2 common insect spawners right there.
Considering Phoebe is working on Gardening and Alchemy, I think I managed to pick a pretty good spot!