Understand sunlight exposure, window placement, and grow light options for healthy indoor herbs in Canadian homes. Proper lighting is the foundation of successful windowsill gardening.
South-facing windows receive the most intense sunlight throughout the day, making them ideal for sun-loving herbs like basil, oregano, and rosemary. In Canadian homes, this exposure provides 6-8 hours of direct light during summer and 4-5 hours in winter. Position pots 30-60cm from the glass to prevent leaf scorch in summer while maximizing light absorption.
North-facing windows receive indirect, diffused light without direct sun exposure. While not ideal for all herbs, mint, parsley, and chives can tolerate these lower-light conditions. Expect slower growth and less robust flavour compared to brighter exposures. Rotate pots weekly to ensure even light distribution across all sides of the plant.
Modern LED grow lights consume minimal electricity while providing full-spectrum illumination for healthy herb growth. Position lights 15-30cm above plant canopy and run for 12-14 hours daily during Canadian winters. Look for bulbs rated 2000-3000 lumens for a 60cm windowsill setup. Initial investment of $30-60 pays for itself through extended growing seasons.
Supplement weak winter sunlight with grow lights to maintain vigorous herb growth year-round. Use natural light as your base and add artificial lighting during early morning or evening hours to extend the photoperiod. This hybrid approach is particularly effective for Canadian homes where December and January offer limited daylight hours. Set lights on timers for consistency.
East-facing windows provide 3-4 hours of gentle morning sunlight, perfect for herbs that prefer moderate light intensity. Cilantro, parsley, and chervil thrive in these conditions without the stress of intense afternoon heat. Morning light is cooler and less likely to cause leaf burn, making this orientation forgiving for beginner indoor gardeners learning to balance light and temperature.
West-facing windows receive intense afternoon and evening sunlight, which can be too strong during summer months. Mediterranean herbs like rosemary, thyme, and oregano handle this heat well, while basil and delicate herbs may require sheer curtains to diffuse the strongest rays. Monitor soil moisture closely, as afternoon sun can dry pots quickly, especially in heated Canadian homes during winter.
Herbs naturally grow toward their light source, resulting in lopsided, leggy plants if left stationary. Rotate each pot 90 degrees every 3-4 days to encourage symmetrical, bushy growth. This simple habit takes seconds but dramatically improves plant shape and vigour. Pay special attention to single-window setups where light comes from only one direction. Consistent rotation produces compact, attractive herbs.
Test light intensity with the shadow method: hold your hand 30cm above the windowsill at midday. Sharp, defined shadows indicate bright light suitable for most herbs. Soft, blurry shadows suggest medium light adequate for parsley and mint. No visible shadow means insufficient light for healthy growth. This free technique helps you assess window quality before investing in plants or grow lights.
Position herbs 15-30cm from the window glass for optimal light without temperature extremes. Too close in summer causes leaf scorch from concentrated heat; too close in winter exposes plants to cold drafts and condensation. During Canadian winters, insulated windows help, but avoid touching foliage to cold glass. Use a shelf or plant stand to maintain consistent distance while maximizing available light.
Insufficient light causes leggy stems, pale leaves, and weak growth with elongated spaces between leaf nodes. Basil loses its intense green colour, while mint becomes sparse and straggly. If you notice these symptoms, move plants closer to the window, add supplemental grow lights, or choose herbs better suited to lower-light conditions. Prompt action prevents permanent growth problems and weak flavour development.