Questions & Answers about Весной мама сажает цветы на клумбе.
Because Russian often uses the instrumental case to talk about seasons when meaning in spring / during spring.
- весна = spring (dictionary form, nominative)
- весной = in spring / during spring
This is a very common pattern:
- зимой = in winter
- весной = in spring
- летом = in summer
- осенью = in autumn
So Весной мама сажает цветы на клумбе means In spring, mom plants flowers in the flowerbed.
Because мама is the subject of the sentence — the person doing the action.
In this sentence:
- мама = the one who plants
- сажает = plants
So мама stays in the nominative case.