Depends on how long it will be until you can plant them. Normally they come with some sort of instructions such as keep dry and cool and out of direct sun until planting or some will say to wrap the roots in damp paper towlrs and store, etc. There were no instructions at all?? If not then I sure would contact the source and ask for instructions.

If all else fails you will need to plant each of them in potting mix - a 1 gallon container for each works well - and then transplant them ASAP.

Dave

I often have to store roots quite a while before planting. Asparagus roots are incredibly tough. I store mine in the crisper in the fridge until ready.