Thanks everyone!
We've been to the pediatrician, and to a dietitian (brought into the Ontario Early Years Centre by the local Health Unit). Both suggested starting solids now, so that we can have an extended "introductory period" with adding a new food every 7 days instead of the usual 3 to 5 days. They also recommended staying away from the most allergenic foods for as long as possible - luckily it's a pretty short list:
peanut (not before age 2 at the very earliest), soy, tree nuts, wheat, cow's milk (not before age 1), strawberries, fish and eggs (no whites before 1).
Hope this info is helpful to others as well!
Esther (Robbie's Mummy)