well the pot you have right now is big enough, but you can take the plant out and refill the pot with improved soil. read the directions on the blood meal bag, and add about 3/4 that amount to your scotts soil, maybe even a little less. alot of people say blood meal can burn easily so be careful measuring. then just mix it up really well and refill the pot about 2/3 of the way, and drop the plant in.
OR
you can top dress the soil in your pot right now. just sprinkle a little blood meal onto the soil around the base of the stem and water it. this is easier, but people say its better to have the blood meal IN your soil. and the pot you are using will be good for another 2-3 weeks, but if i were you i'd refill it with new soil.