Dashu (大暑): Major Heat and the Peak of Summer
Dashu (大暑, Major Heat) is the twelfth solar term, reached when the sun stands at longitude 120°. It closes the summer half of the calendar, and in Korea it lines up with the hottest, most humid stretch of the year.
When it arrives
In haru's figures Dashu falls at 04:13 KST on 23 July 2026 and at 10:05 KST on 23 July 2027, a year-on-year shift of 5 hours 52 minutes. It is a qi term, so the month pillar does not change: the 未 month continues (乙未 in 2026, 丁未 in 2027). The next term, Liqiu, comes 15 days 16 hours 30 minutes later in 2026 and 15 days 16 hours 22 minutes later in 2027.
The name
大 is great and 暑 is summer heat: this is the 'big' heat that Xiaoshu promised. Older almanacs describe it with two words, heat and damp together, and that pairing sums up the season better than temperature alone. It is the last term of summer; the very next one, Liqiu, already carries the word autumn, even though it rarely feels like it.
What nature is doing
In Korea the rainy front usually moves north around late July, and the steady heat of high summer settles in. Tropical nights (열대야), when the temperature stays high after dark, are common. In the old almanac the three pentads of Dashu are:
- 腐草為螢 - fireflies rise from rotting grass
- 土潤溽暑 - the soil is damp and the heat is sticky
- 大雨時行 - heavy rains come at times
| Recipe id | Dish | Element(s) | Nature |
|---|---|---|---|
| cucumber_seaweed | Chilled cucumber-seaweed soup, black bean rice | Water | cool |
| mung_bean | Mung bean porridge | Wood · Water | cool |
| abalone_porridge | Abalone porridge | Water | even |
| tomato_egg | Tomato and egg stir-fry | Fire | even |
| sweet_potato_rice | Sweet potato and corn rice | Earth | even |
| chive_pancake | Chive pancake | Wood | warm |
Eating in the great heat
The table above lists every dish that haru's recipe book marks for summer. Notice that most are cool or even in nature and only one is warm. That is the tradition's approach in a nutshell: when the season leans hot, balance the table toward cooling foods such as cucumber, pear, mung bean, tofu and lotus root, without swinging to icy extremes. haru also lists foods to cut back on in hot conditions: spicy stir-fries, deep-fried food, alcohol and strong coffee.
Korean summer favourites fit the same idea: chilled noodle soups, watermelon, Korean melon, and, on the boknal days, a warming bowl of samgyetang.
Korea around Dashu
Jungbok, the middle of the three dog days, often falls close to Dashu, and this is peak holiday season for beaches and valleys. A folk saying claims that at Dashu even a goat's horns melt (대서에는 염소 뿔도 녹는다), a vivid way to describe the heat.
Gentle habits for the hottest weeks
Yangsheng for Dashu is mostly about timing:
- Move the day's activity toward early morning and after sunset.
- Rest for a short while in the 未 hour after lunch, when the heat is fiercest.
- Sip water steadily through the day rather than gulping iced drinks.
- Water-side walks or slow swimming suit the season well.
- Keep the bedroom airy so tropical nights are easier to sleep through.
A line of poetry
Yang Wanli (楊萬里), Song dynasty, 'Seeking Cool on a Summer Night' (夏夜追涼): 「夜熱依然午熱同，開門小立月明中。」 - 'The night is as hot as noon; I open the door and stand a while in the moonlight.'
Questions
Is Dashu the hottest day of the year?
It is the traditional marker of the hottest season. The actual hottest days vary by year and place, but in Korea late July to mid-August is typically the peak.
Why does haru favour cool dishes now?
The five-element tradition balances a hot season with cooler foods. It is a general lifestyle habit, not medical advice.
Does anything change in the calendar at Dashu?
The month pillar stays the same. Dashu is a qi term inside the 未 month; the month changes at Liqiu.
Recipes for this season
Read next
Traditional Four Pillars (myeongni) and yin-yang five-element interpretation. Not a medical diagnosis or advice.