my 1 year old baby is having blocked nose... it's irritating him at night... and he also have phlegm

Try home remedies like steam to help him

U can try ajwain potli.

Remedy from a Babychakra momstar. Apply Kesar khad.... Take Kesar heat it wid very little milk.....N den apply on hand n leg nails n on forehead....

mustard oil is useful or not

Put drops of nasoclear in his nose. You can also apply drops of eucalyptus oil on his clothes.

You can use eucalyptus oil in a diffuser in the room that the baby sleeps in. Additionally a suction massage on the chest will help to loosen the phlegm and the baby will cough it up. To do a suction massage take a very small measuring cup the type you get with baby medicine bottles and place them with light pressure on the baby's chest. Then move it away. Repeat in different parts of the chest. Can do this a few times a day.