For house plants. how do they get the nutrients in sunlight through the windows?

Nutrients come from the soil. And you have to replenish the nutrients in the soil periodically or the house plant will die. Depending on the plant watering can add enough nutrients to the soil to sustain it for a very long time. But other plants require fertilizer or nutrient mix added to the soil or even frequent repotting with new soil. There are other reasons why you have to repot plants periodically as well.

The sunlight through the window is providing energy for photosynthesis. And that does pass through the window. Many houseplants don't need that much direct sunlight so even getting less through the window is still more than enough. But a few plants do struggle unless you get a lot of sunlight through your window.

/r/NoStupidQuestions Thread