2台per series of four · All four plants (梅蘭菊竹) or all four seasons (春夏秋冬): 2 tai, in place of that series' own flower. The other series' own flower still counts.
Example
chow二萬2三萬3
四萬4五萬5六萬634772349995
flowers1梅2蘭3菊4竹2夏
South self-draws, East round, East deals.
Self-draw 自摸 1 + Own flower 正花 1 + Flower set 花槓 2 = 4 tai
In one line2 tai by default (per series of four). Other values: MJOnline (戲谷) 1, zh Wikibooks 2, plus 正花.
Conditions
You hold all four flowers of one series.
Both series complete means all eight flowers: that scores 八仙過海 instead.