Any buy one, get one free offer will be accompanied by an offer code. Please make sure to add the offer code into the offer code box on checkout to make sure you get the free plant - if you don't,  we won't know you want it,  therefore we won't send you a free plant.  

In most cases, just adding the first plant to the basket and then the offer code on checkout will add the free plant to your basket automatically. But if there is a choice of free plants, you will need to add this yourself.  Just choose the plants you want, and when you add the offer code, it will adjust the price so one is then free. 

Do the same if you have a three for two offer. 

Just make sure you check that any free or reduced priced plants are showing in your basket before checkout to make sure you get what you expect.