The year according to Ayurveda is divided into two kalas

Aadaan kaal (Uttarayan) (Northeren Solastice) includes sishira,vasantha grishma ritu.

Visarga kaal (Dakshinayaan) (Southeren Solastice) includes varsha ,sharat,hemanta ritu.

This division is done according to the position of the sun. Aadaan means taking away and visarga means giving. In aadan kaal, the sun and wind are powerful. The sun takes away the strength of the people and the cooling qualities of the earth. It is the debialiting period. strength is weakened . In Visarga kaal , the sun releases the strength to the people. The moon is more powerful, the earth becomes cooled due to the clouds, rain and cold wind.A year consists of six ritus (seasons). Each ritu is two masas (months) long. Three ritus (one semester) form a kaal. The Six Ritus The six ritus and their properties can be summarized in the following table

Sisira Ritu (late winter)

During this rithu sweet,sour and salt taste food can be taken. In this season the digestive activity becomes more powerful. Increased vata gets obstructed from spreading out due to cold atmosphere outside which can digest the tissues. More intake of sweet, sour and salt helps reducing the vata. Wine prepared from jaggery (molasses) can be taken.

Wheat/gram flour products, milk products, sugarcane products and corn/edible oils can be taken as a part of food. Massage with oil. Ubvartan with fine paste/powder of kumkum (kesar). Exercise (vyama). Clothing-leather, silk and wool. Exposure to sunlight and fire to keep yourself warm.

Vasanta Ritu (Spring Season)

In this season, increased kapha is liquified by the heat of sun which causes diminished agni (digestive activity) causing diseases Easily digestible food. Barley, honey, roasted meat, mango juice can be taken as food. Beverages such as asava (fermented infusion), arista (fermenteddecoction), sidhu (fermented sugarcane juice), honey mixed with water and water boiled with extracts of chandan (sandal wood). Avoid hard to digest and cold food, sour, sweet and fatty food. Such food increase kapha causing dosha imbalance and hence genesis of disease Physical exercise.

Dry massage. Nasal medication can be taken. After massage bath with karpura/chandan/kumkum.

Grishma Ritu (Summer Season)

ISweet, light, fatty and liquid food can be taken. Wine should not be taken as it can cause burning sensation and even debility. If neccesary take in very little quantity. Boiled rice with meat, cornflour, curd (yoghurt) can be taken in food. Drink very cold water. Panak Panchsara (syrup prepared with draksha (sugarcane), madhuka, date, kashmarya and parshuka fruits all in equal quantity cold with cardamomn this season, Sunrays become powerful. Kapha decreases vata increases day by day.

Anoint body with chandan paste and take bath with cold water.Stay in cool places.

Wear light dresses.

Varsha Ritu (Rainy Season)

The agni (digestive activity) weakens further and gets vitiated by doshas.Hence all methods to mitigate doshas and measures to enhance digestive activity can be adopted. Easily digestible food to be taken. Pulses, meat juice, soups, old grains and mastu (thin water of yoghurt ) can be taken in food. Panchkarma can be done.

Perfumes can be used. Avoid sleeping at daytime, exertion and too much exposure to sunlight.

Sharat Ritu (Autumn Season)

Sudden exposed to sunlight after cold season aggravates pita. Bitter, astringent and sweet taste can be included in food. Take easily digestible food like rice, green gram, amla, honey and sugar.Avoid heavy food, curd, oil, strong liquors. Udvartan with chandan. Bath with warm water. Pearls give soothing effect from aggravated pita.

Hemant Ritu (Winter season)

As digestive fire is very stronge one should take diet consisting of sweet ,sour ,onctous and salty items milk and its productssweets and cereals.take bath with warm water.Avoid direct exposure to cold.Physical exercise and oil massage regularly.