Q. Thank for answering the last questions we sent. We were wondering why is it that no one seems to care if it is permitted to open the shades or curtains on Shabbos morning, to let the sunlight in when there are flowers or plants growing inside and the sun will make them grow better. Should that not be prohibited because it amounts to promoting planting or being ‘Zorea’? Thank you.
A. Poskim disagree. Machaze Avrohom (52) deals with the issue of uncovering the walls or roof of a greenhouse to let the sun in. He quotes Iglei Tal (Zorea 22), that it should be prohibited since even if the plants will eventually grow anyway, letting in the sun rays will speed up that growth. He debates whether the prohibition is Biblical or only Rabbinical and he leans to be lenient, since it is only a ‘Gramah’ or an indirect act, especially if he opens the shades before the sunlight actually reaches the plants (See Chassam Soffer Y.D. 214 and Maharsham 3: 44)
However, Shevisas Shabbos (Zorea 10) prohibits. Similarly Chazon Ish rules likewise regarding Shemita. (Shevi’is 22: 1).
Horav Shlomo Miller’s Shlit’a opinion is that it is permitted when done inside the house and no special intention of promoting growth is involved.
Rabbi A. Bartfeld as advised by Horav Dovid Pam, Horav Aharon Miller and Horav Chanoch Ehrentreu Shlit’a