Phaalgun or Phaagun Maas is the last month of the Hindu Lunar calendar. Only two main Vrat and festivals fall in this month.

Phaalgun Krishn 14 - Shiv Raatri Vrat
Shiv Raatri is the day of Shiv Jee. It is said that this day Shiv Jee drank Halaahal Vish (poison) which came out of Saagar Manthan. And it is also said that Shiv Jee was married to Paarvatee Jee on this day. people keep fast on this day, spend the whole night singing Shiv's devotional songs and doing his Abhishek 3-4 times.

Phaalgun Shukla Saptamee
Recite Soorya Gayatri on this day - although even one time is enough but still recite it 108 times if possible] Eat Moong, Pooaa, milk, yogurt.
Om Bhaaskaraaya Vidmahe Sahastra Rashmim Dheemahi Tanno Soorya Prachodayaat

Phaalgun Poornimaa - Holee
This day is celebrated as Holee. It is said that this day Hiranyakashyap's sister Holikaa sat in fir to burn Prahlaad at the order of her brother. As she had a boon that she would not be burnt in fire, Hiranyakashyap asked her to burn Prahlaad; but unfortunately Holikaa herself got burnt and Prahlaad got saved. To commemorate this event people collect piles of wood, tree branches etc and then burn it.

The women who have sons, keep fast on this day, worship that pile of wood before burning to pray God for the long life of their sons. Next day, on Chaitra Krishn Pratipadaa people play Holee by throwing dry and wet colors on each other. Nobody feels any bad of anything done by others. Many relationships are renewed on this day. Thus this festival is the festival of ending even long lasting enmity and extending friendship also.