As per Ayurveda English months March. 15 to May. 15 ( Indian calender months of Chaitra and Vaishakh) constitute the Vasant Ritu.
Detoxifying in spring is an important part of the ayurvedic seasonal routine- "Ritucharya".
Spring is the Kapha season, because the wet and cool weather reflects the moist, cool, heavy qualities of Kapha dosha that predominate during this time of the year.
Biologically, nature supports cleansing of the body in spring. In winter the digestive fire is high, and people eat more sweet and heavy food. Most of the time they aren't able to assimilate these hard-to-digest foods, so Ama (the sticky, toxic product of indigestion) starts accumulating. When the warm weather melts the snow in spring, it has a similar effect on the body. In spring the Ama melts and the volume of Ama becomes so great that the 'shrotas'[the micro circulatory channels of the body]become clogged. Increased kapha is also liquefied by the heat of sun which causes diminished agni (digestive activity) causing diseases
If you don't assist these toxins in moving out of the body, you can become prone to flu, colds and cough, or allergies. You might feel unusually fatigued, sluggish or drowsy after lunch, or lose your appetite. sharp headaches, dizziness, mild tremors in the limbs, and unexplained muscle aches, especially in the calf, can also be symptoms. Your tongue may be coated, and your throat may be sore.
Spring is the best season for detoxification, because nature is already trying to clear out the toxins. It's the time to help the body to efficiently detoxify the channels and the dhatus [body tissues].
Diet and Lifestyle in Spring -
A Kapha pacifying diet and lifestyle is best. If you avoid eating heavy, cold, hard-to-digest foods, and avoid or reduce the sweet, sour, and salty tastes, your digestive system will be more efficient in burning away the accumulated Ama.
Sweet juicy fruits can help cleanse the body, although they should be eaten before sunset, as they have a Kapha-increasing effect after the sun goes down. And you can add spices to your food -- such as coriander, cumin, turmeric, and fennel -- to help stimulate the digestion and detoxify the skin.
In spring you can sip hot (if you are a Pitta body type or have a Pitta imbalance then drink warm) water to help melt the Ama (digestive impurities) that have accumulated. Daily exercise, and avoiding day sleep will also help.