1 GB in terms of how many photos/images you can upload. For texts, no limits, I didn't found anywhere on the internet where limit for text-input has been mentioned.
For more limitations on blogger, go here.
"Number of Blogs: You can have up to 100 blogs per account.
Number of Posts: There is no limit on the number of
posts you can have on one blog. They will all be saved on your account
(unless you manually delete them) regardless of whether you are
publishing archives or not.
Size of Posts: Individual posts do not have a
specific size limit, but very large posts may run you up against the
page size limit. (See the next item.)"