I will tell you what i know about potatoes and their uses in magic.
Like the tomato, it is a member of the nightshade family. Also like the tomato (which we know is a fruit), the potato is used for protection. Potatoes are ruled by the moon and their element is earth.
They are also very good for grounding. Potatoes eaten for protection should be seasoned with onions, chives, rosemary, parsley, or dill for maximum effect. Potato dishes are good to eat after energy has been raised, in order to help ground the participants. I haveeaten potato soup after meditation to help me ground myself.
You can find some magical uses for a lot of things you have known just as food or ordinary daily items. I told you what i use potatoes for, but of course that not everyone uses them for the same reasons, of course there are a lot of magic properties and uses for potatoes that i might not know. You can research about it and find many interesting uses of potatoes, including magic or just health properties, all of the information you may see and read can be very helpful to you and your magic studies.
I am sure that you can use potatoes for the magical properties you have brought, writing your own spells and rituals about it. I could not bring you any good example of a spell which potatoes are used in them, i told you what i use potatoes for in my magic workings.
If you do want to use potatoes for your spell or for your rituals, you can search for such spell, but i can not promise you that it will be really easy to find, but that's why we have search engines for. You can choose to make your own spell, including potatoes in, using them for the properties you have brought : "Image magic, money, luck, and healing". Again, i have never used potatoes for such reasons, and i can not really bring you a spell with those properties including using potatoes.
Lets not forget that if you are not sure you want to use potatoes for those specific uses and you do not know how to include them to your spells, you can find or write your own spells including other herbs and so... You have a big choice of spells for a lot of needs, you can check them out in this site or in another one.
If you are interested in potatoes and their magic properties, i told you what i use them for,and if you want you can use them for the same reasons. Again, search engines are very helpful nowdays, if you are sure you need a spell which needs you to use potatoes, go for it and search. Or make your own spell / ritual including potatoes.
I use potatoes for several years (i told you for what), but not everyone has to do the same. Do what you will, and if you took this information from a good and trusted source - you could give it a good try...