The question was recently asked whether or not it is permissible to put flowers in water on Shabbat? It could easily happen that a person receives some roses on Friday right before Shabbat and does not have the time to put the roses into a vase with water. So can this person fill a vase with water and put the roses in the vase on Shabbat?
The answer to this question varies based on if the roses are fully opened or not. If the roses are fully opened, it would then be permissible to put the flowers into the vase with the water. It would not be a problem of Zorea (planting) because these flowers are already cut and can not grow or bloom any more. But if the roses are closed, or if they are not fully opened, it would then be forbidden to put them into a vase with water on Shabbat. Putting these closed flowers into water would cause them to further open and therefore, it is forbidden if the roses are not fully opened. This is based on Maran, and it is also the way Chacham Ovadia Yoseph writes in his sefer Yichaave Da’at, Helek 2, siman 53. It is also brought down his sefer Halichot Olam.
It would also be permissible to change water or add water to a vase of flowers on Shabbat, but so long as the flowers are fully opened. Many times in shul we want to change the water of a vase that is holding Hadasim. We want to keep the Hadasim fresh. This would be Lechatchila permissible, because the Hadasim are already cut and fully developed.
The question was then asked about opening a window near a plant on Shabbat. Can someone open shades and a window on Shabbat if there is a plant nearby that will come to grow due to the open window’s sunlight and air? Chacham Ovadia Yoseph is lenient on this case and permits opening the shades and window on Shabbat. One would be allowed to open the shades and window because his intent is to let air and sunlight into the home and not for the purposes of growing the plant. It is permissible even though it is a Pesik Rashe (which means that a transgression is inevitable for it is a byproduct of the permissible function.) Now, of course one would not be allowed to open the shades and window if the intent is in fact to provide air and sunlight to the plant. It is only permissible if the intent is to let air and sunlight into the general home.
So to review, it is permissible to put opened cut flowers in water on Shabbat. You can change the water or even put new water in the vase on Shabbat, so long as the flower is opened already and will not open any more. It is also permissible to open the shades and window on Shabbat if your intent is to bring air and sunlight into the room and not cause the plants to grow.
