Windham Fabrics and Michael Miller Fabrics are also two brands that you can always trust! I don't know what type of fabrics you are looking to include in your Grandmother's Flower Garden, but Windham has some nice feedsack prints.
We sell 1/4 yard cuts of any of our fabrics that are sold by-the-yard... which, as someone else mentioned, is much more budget-friendly than having to buy a full yard!
Some fabrics are sold by the panel or pattern repeat and of course those we wouldn't sell a partial cut of, because it ruins the design for the next person.