My orchids which are on a West facing window on the window ledge used to re-flower regularly. Since replacing windows with very lightly tinted windows 2 years ago they have stopped re-flowering Is there anything I can do as I have no other suitable windows to put them.
Thank you for contacting the Toronto Master Gardeners’ regarding your orchid that has not re-bloomed in the past 2 years. Insufficient light is perhaps the most common reason that orchids don’t re-bloom. It is possible that even the minimal tint on your west-facing window does not allow sufficient light for your orchid – especially over the winter months. The American Orchid Society states that pale green leaves (rather than lush darker green), similar to the colour of grass, indicate optimal plant health for re-blooming. Other factors including temperature, moisture, root health and potting mixture and fertilizer as well as the type of orchid you have will impact blooming frequency. If you are limited in suitable window space for growing, you can supplement light or grow orchids entirely under electric lights. The American Orchid Society has a detailed page outlining how to grow orchids under lights. I have attached links to this reference as well as the Toronto Master Gardeners’ Orchid Gardening Guide below for further information.
Best of luck with your orchids!
https://www.aos.org/orchids/additional-resources/growing-under-lights.aspx