Pots
Pots are a versatile way of putting plants of all shapes and sizes in positions that work for you and them. They can also allow you to 'move your garden around' adjusting for the seasons and for additional plants.
Creating a bigger space with a bed, perhaps in addition to your pots, means you could create a whole garden. You could make a herb or vegetable patch to complement your flower pots and give you the ability to 'grow your own'.