Do trees drop furniture in all colors and varieties or only the types sold in the shop in ACNH?

Solution 1:

Trees only drop furniture of the colors found in your shop.

I time traveled for another month and shook my trees every day. I didn't get any new furniture. I did get several more items that appear in my shop:

• Red imperial furniture (shelf and screen)
• Brown rattan furniture (waste bin and end table)
• White cute furniture (sofa and tea table)

I guess I can't say for sure that they would NEVER drop new furniture, but if they do, they do it so rarely that it is not a feasible way to get all the colors of furniture in a reasonable amount of time.

During this time I visited Redd a few times and got new furniture pretty much every time:

• Box corner sofa in two colors I didn't have before
• Rattan stool in light brown

I also popped a balloon and received a blue cute wall-mounted clock.

Balloons and Redd will give you furniture colors not sold in your shop but your shop and trees seem to be limited to the same color for series of items.