The legal battle over baubles and fir branches dates back several years - and is linked to German employment laws.
Garden centres in the western German state of North Rhine-Westphalia (NRW) are allowed to sell decorations, including Christmas decorations, on Sundays - in addition to flowers and plants.
That's according to a ruling given by Germany's Federal Court of Justice on Thursday.
The decision comes amid a battle linked to the country's trading laws, specifically rules about what shopkeepers are allowed to sell on Sundays.
Two years ago, a garden centre chain in NRW was hit with a cease-and-desist notice.
As well as offering its main product range on Sundays, it began to sell artificial fir branches, cinnamon sticks, glass balls and other Christmas tree decorations.
In the eyes of the competition authority, this practice was unfair, as the shop wasn't adhering to trading laws, giving them an edge over other stores.
Decorations accompany core offerings
Germany's Federal Court of Justice last week sought to clarify mixed messages, as regional courts within NRW have previously made different decisions on Sunday sales in the past.
The competition authority's lawsuit regarding the decorative items had already failed before the regional court in Bochum and the higher regional court in Hamm.
The law in NRW stipulates that certain shops can open for five hours on Sundays - including stores that offer baked goods, newspapers, and flowers.
Core goods can be sold in these stores, as well as related items.
The Federal Court of Justice ruled that Christmas decorations can be classed as related goods for garden centres.
In other words, they accompany the plants sold as core items - such as Christmas trees - and can therefore be sold on Sundays.
This doesn't mean customers need to buy them as a bundle.
It's unclear whether the ruling in NRW will have implications for the rest of Germany.
Keeping Sunday sacred
The country's trading laws aren't without their critics, with some arguing that they are too inflexible.
The practice of preserving Sunday as a rest day is actually enshrined in Germany's constitution, which forms the basis of shopping restrictions.
Earlier this year, the German supermarket Tegut made headlines when it was forced to close its shops on Sunday.
This was despite the fact that the firm was using automated check-outs, meaning no staff interactions were required.
Despite the automated service, unions were concerned that the store would set a precedent and lead to a wider loosening of Sunday rules.