Wait a bit longer. Most babies are ready to start eating solid foods
when they're between 4 to 6 months old. Why? Because in order to eat
solid foods, an infant needs good head and neck control and should be
able to sit up. Your son may not be able to do these things until he's 4
to 6 months old. Before this age, you may notice that he pushes the
food out of his mouth just as quickly as you put it in. Babies start to
lose this natural tongue-thrusting reflex around this time, which will
make it easier for him to start eating solid foods.
And don't worry about not introducing new foods early enough. During a
baby's first 6 months, water, juice, and solid foods are usually
unnecessary. Up until this point, breast milk or formula provides
everything babies need nutritionally.
When you begin to introduce foods to your baby, start with a
single-grain baby cereal (iron-fortified rice cereal is usually the
best choice) on a spoon before moving on to pureed fruits and
vegetables. Introduce only one new food at a time and wait
several days before starting another. This will give you a chance to
see if your baby is allergic to the new food.
Also, it may take several tries before your child starts to enjoy a
new food so don't give up after the first or second attempt if he
doesn't seem to like it.