Sorry, but what is Hebert? A photo would help.
The likely causes of yellowing leaves are:
Watering - could be not enough water but also could be too much water!
Not enough light - move pot to a lighter position
Nutrient deficiency - repot into fresh compost or use a general purpose fertiliser
Pot bound - are the roots coming out of the bottom of the pot? Repot into the next size pot with fresh compost.

And Finally - that's the variety of plant.