It is often believed that it was on this day Kamadeva, the god of love, was incinerated by Lord Shiva. While meditating, the formidable Shiva, angered at being disturbed opened his famous third eye and reduced Kama to ashes. But he was brought to life again when his wife, Goddess Rati, implored Shiva for mercy. After the death of his consort Sati, Lord Shiva was so shocked and hurt that he went into a deep meditation and stopped looking after his worldly responsibilities. This led to many complications in the world's affairs. Thus, the other gods conspired to bring him out of his trance with the help of Goddess Parvati, who wished to marry the great Lord.
Kāmadeva (Sanskrit: कामदेव) is the Hindu deity of human love  or desire. Other names for him include; Atanu (one without a body), Ragavrinta (stalk of passion), Ananga (incorporeal), Kandarpa ("inflamer even of a god"),   Manmatha (churner of hearts), Manasija (he who is born of mind, a contraction of the Sanskrit phrase Sah Manasah jāta), Madana (intoxicating), Ratikānta (lord of Rati), Pushpavān, Pushpadhanva (one with bow of flowers) or just Kāma ("longing"). Kamadeva, is son of Hindu goddess Sri and, additionally, is the incarnation of Pradyumna, Krishna’s son.
The name Kama-deva (IAST kāma-deva) can be translated as 'god of love'. Deva means heavenly or divine. Kama (IAST kāma) meaning "desire" or "longing", especially as in sensual or sexual love. The name is used in Rig Veda (RV 9, 113. 11).  Kamadeva is a name of Vishnu in Vishnu Purana and Bhagavata Purana (SB 5.18.15) and of Krishna as well as of Shiva. It is the name of author of Sanskrit work Prayaschita padyata. Kama is also a name used for Agni.
Kāmadeva is represented as a young, handsome winged man who wields a bow and arrows. His bow is made of sugarcane with a string of honeybees, and his arrows are decorated with five kinds of fragrant flowers. The five flowers are Ashoka tree flowers, white and blue lotus flowers, Mallika tree(Jasmine) and Mango tree flowers
he story of the birth of Kamadeva has several variants in different Puranas. In some Kamadeva arises from the mind of the creator god, Brahma: in others he is the son of Sri. Kamadeva is sometimes portrayed as being at the service of Indra: one of his names is "obedient to Indra". Kamadeva's consort Rati, whose very essence is desire, carries a discus and a lotus, her arms are compared with lotus-stalks. Rati is a minor character in many traditional dramas involving Kamadeva and in some ways represents an attribute. The goddess Vasanta, who also accompanies Kamadeva, emerges from a sigh of frustration. Kama often takes part in Puranic battles with his troops of soldiers.
The incineration of Kama: Madana-bhasma
one of the principal myths regarding Kama is that of his incineration by Shiva. It occurs in its most developed form in the Matsya Purana (verses 227-255)  but is also repeated with variants in the Shaiva Purana and other Puranas  .
Indra and the gods are suffering at the hands of the demon Tarakasur, who cannot be defeated except by Shiva's son. Brahma who advises that Parvati woo Shiva; their offspring will be able to defeat Taraka. Indra assigns Kamadeva to break Shiva's meditation. To create a congenial atmosphere, Kamadeva (Madana) creates an untimely spring (akAl vasanta). He evades Shiva's guard, Nandin, by taking the form of the fragrant southern breeze, and enters Shiva's abode.
After he awakens Shiva with a flower arrow, Shiva, furious, opens his third eye, which incinerates Madana instantaneously and he is turned into ash. However Shiva observes Parvati and asks her how he can help her. She enjoins him to resuscitate Madana, and Shiva agrees to let Madana live but in a disembodied form, hence Kamadeva is also called 'Ananga' (an- = without; anga = body, "bodiless"), or 'Atanu' (a- = without; tan = body). The spirit of love embodied by Kama is now disseminated across the cosmos: it affects Shiva whose union with Parvati is consummated. Their son Kartikeya goes on to defeat Taraka.
This story is used in the Matsya Purana to underline a relationship between Krishna and Kamadeva.  Later Kama is reincarnated in the womb of Krishna's wife Rukmini as Pradyumna. Vaishnavas believe he is not the Pradyumna (name of Vishnu) but belongs to the category of jiva-tattva, or conditioned souls and, due toting special power in the category of demigods, devas, he became a part of the prowess of Vishnu form Pradyumna. This is the view of the Six Gosvamis, who maintained that Kamadeva was burned to ashes by the anger of Shiva and later merged into the body of Vasudeva. And it is explained that in order to get his body again he was placed in the womb of Rukmini. Particularly in the Gaudiya tradition, Krishna is identified as Kamadeva, and in Gaudiya Vaishnavism, Kamadeva is directly a part of Vasudeva. It is believed that because he was begotten by Krishna himself, his qualities were similar to those of Krishna, such as his colour, appearance and attributes. 
The attributes of demigod Kamadeva are as such: his companions are a cuckoo, a parrot, humming bees, the season of spring, and the gentle breeze. All of these are symbols of spring season, when his festival is celebrated as Holi, Holika or Vasanta.
According to the text Shiva Purana, Kamadeva is a son or a creation of Brahma, while according to other sources including the Skanda Purana, Kamadeva is a brother of Prasuti; they are both the children of Shatarupa, a creation of Brahma. Later interpolations consider him the son of Vishnu  Kamadeva is wed to Ratī, the daughter of Daksha, created from his sweat.
The deity of Kamadeva along with his consort Rati is included in the pantheon of Vedic-Brahmanical deities such as Shiva and Parvati.  In Hindu traditions for the marriage ceremony itself, the bride's feet are often painted with pictures of Suka, the parrot vahana of Kamadeva.  One should not misunderstand or associate worship of Kamadeva, as being sexually oriented, as the religious rituals addressed to him offer a means of purification and reentry into the community. Devotion to Kamadeva keeps desire within the framework of the religious tradition.  Kamadeva also appears in other stories and becomes the object of certain devotional rituals for those seeking health, physical beauty, husbands, wives, and sons. In one story Kamadeva himself succumbs to desire, and must then worship his lover in order to be released from this passion and its curse.
According to some traditions worshiping Radha Krishna, Radha is without equal in the universe for beauty, and her power constantly defeats the god of love, Kamadeva.  However when Krishna played his flute, as described Bhāgavata Purāṇa, book X, the women of Vraja heard that flute music, and this music which incites even Kama, attracted them to Krishna, the original Kamadeva. 
Holi as a Spring New Year Festival In southern India and many western regions. It is sometimes called Madana-Mahotsava in Sanskrit, or Kama-Mahotsava. Some have suggested that the replacement of Kamadeva by Krishna, had its germ in the early medieval period. Initially spring festival Holi was being held in reverence to celestial Vedic figure of Kamadeva, however it is presently dedicated to Krishna.  This festival is mentioned in Jaiminis early writings such as Purvamimamsa-sutra, dated c.400 BC.  According to Gaudiya Vaishnava theologians of medieval period, when in Bhāgavata Purāṇa, book X, Kamadeva is mentioned by the word smara he is not the deva who incites lusty feelings. Its believed that the gopis are liberated souls beyond the touch of material nature, therefore according to Gaudiya views it is not possible for them to be contaminated by the lust which is produced of the mode of passion. 
According to the Matsya Purana, Visnu-Krishna and Kamadeva have a historical relationship.  Krishna is sometimes worshiped as Kamadeva in Gaudiya traditions, and according to the Krishna-centric Gaudiya Vaishnavism, Kamadeva was directly a form of Vasudeva Krishna after this deva was burned down by Shiva. In this particular form Kamadeva is believed to be a demigod of the heavenly planets especially capable of inducing lusty desires. Some Vaishnavas distinguish a form of Kamadeva who is a deva, demigod in charge of inciting lusty desires, the cause of generation and referred to in the Bhagavad Gita with the words “prajanas casmi kandarpa.” It is this Kamadeva who tried distract Lord Siva from deep meditation with his passionate influence and feminine associates. He is distinguished from spiritual Kamadeva. 
Krishna is believed by his bhaktas, devotees, to be the inciting power of Kamadeva and is known as the ever-fresh transcendental god of love of Vrindavana.  He is believed by Gaudiyas to be the origin of all forms of Kamadeva, but is considered above mundane forms of love in the hierarchi of devotional rati, raga, kama, and prema.  
The word smara in the tenth book of Bhagavata Purana refers to Krishna, who through the medium of his flute ever increases his influence on the devoted gopis. This, according to Vaishnavas, is the meaning of the word smarodayam in Bhagavata Purana (SB 10. 21. 3) The different symptoms of smarodayam as experienced by the gopis has been described by the commentator Vishvanatha Cakravarti Thakur in the following way:  "First comes attraction expressed through the eyes, then intense attachment in the mind, then determination, loss of sleep, becoming emaciated, uninterested in external things, shamelessness, madness, becoming stunned and death. These are the ten stages of Cupid’s effects." 
The tree is often planted near temples. The tree is said to be a symbol of love and is dedicated to Kamadeva. 
Kama Gayatri Mantra || om kaam devaay vidmahe pushpabaanaay dheemahi tanno ananga prachodayat || 108 Times in Pradosh Kaal(Evening Time or twilight) (Preferably From Basant Panchami till Holi)