Police, appealing for information, say the festive goods taken from Dobbies Garden Centre on Dechmont roundabout are worth a five-figure sum.
They have urged anyone offered cut price Christmas decorations to get in touch as as soon as possible.
The raid was staged some time between 6pm on Friday, November 29 and 8am on Saturday, November 30.
Detective Constable Marc Lunn said: “I am appealing to anyone who was in the area on Friday night or Saturday morning to get in touch if they saw or heard anything suspicious.
“I would also ask anyone who may have been driving in the area around the time to review any dashcam footage and report anything which may be of use to us”.
Anyone who can help should contact police via 101, quoting reference number 1365 of November 30, or contact Crimestoppers anonymously on 0800 555 111.