Picnic Blanket Progress - One Black Ball Down

This is as far as one skein of black "Vanna's Choice" gets me. I only have 3 skeins of black so this is going to be the main factor in how large I can make this since I think I probably have more than enough scraps of the rest of the colours.

Ideally I'd like to finish the whole blanket with a single crochet border. I suppose black is a pretty generic colour so I could use another brand to make the trim if I run out of Vanna's choice.

So far it measures 27" x 22.5" (69cm x 57cm) and is made up of 30 motifs. 

Each motif is 4.5" (11.5cm).

I've used a 4.5mm hook.

The pattern comes from "101 Crochet Blocks" by Jean Leinhauser (link below).