My DS2 is almost 7 mths, 17#13oz and he is getting one taste of solids a day if we're lucky. It's usually some banana in the baby safe feeder to keep him occupied while we deal with other household things. We've had other more important things going on with DS1's health so we've been distracted and haven't made a concerted effort on the solids. He is growing just fine on breastmilk.
As another poster said, breastmilk or formula is complete nutrition and all your child needs for the first year of life. Solid foods are just practice and generally shouldn't be started until babies show all the signs of readiness, which is generally around 6 mths.