Dealing with Shorter Days: Light for Houseplants in Autumn

Relocate and Reposition

That spot a few feet from the window that was perfect in June might be a dark corner by October. The sun's path is lower and shorter, so it’s time to move your plants. Gather them closer to your brightest windows-typically south-facing ones are best in the Northern Hemisphere. Don't be afraid to put them right on the windowsill; the autumn sun is rarely strong enough to scorch their leaves.

If you’ve just brought plants indoors, reduce shock by following Preparing Houseplants for Winter.

Clean Your Windows and Leaves

It might sound trivial, but clean surfaces let more light through. A layer of dust and grime on your windowpanes can significantly filter the already limited sunlight. The same goes for your plants' leaves. Dust accumulation blocks their ability to photosynthesize. Gently wipe down larger leaves with a soft, damp cloth to help them soak up every available ray.

Rotate Regularly

Plants are phototropic, meaning they grow towards their light source. To ensure even growth and prevent them from leaning heavily in one direction, give them a quarter turn every time you water.

You Don't Need a Science Lab

The term "grow light" can sound intimidating, but it doesn't have to be complicated or expensive. For most houseplants, a simple full-spectrum LED bulb is all you need. You can find these bulbs online or at garden centers, and they are designed to screw into standard desk lamps or light fixtures. They are energy-efficient and provide the quality of light your plants crave.

How to Use Your Grow Light

Position the light directly above the plants, about 6 to 12 inches away from the foliage. Keep the light on for 12-14 hours a day to mimic a natural light cycle. Using an automatic timer is the easiest way to ensure consistency. Remember that plants also need a period of darkness to rest, so don't leave the light on 24/7.

If leaves still yellow after improving light, check Common Autumn Houseplant Problems.

Which direction should my windows face for the best light in autumn?

South-facing windows provide the most intense and longest-lasting light, making them ideal. East and west-facing windows are also good, but you may need to move plants closer to them than you did in the summer.

How many hours a day should I run a grow light?

For most houseplants, 12 to 14 hours of supplemental light per day is a good target. It's best to use a timer to keep the schedule consistent, mimicking a natural day-night cycle.

Can my plant get sunburned in the autumn?

It's much less likely than in summer, as the sun's rays are less intense. Moving most plants directly into a south-facing window is generally safe in the fall. However, keep an eye on delicate plants for any signs of scorching.

My plant is stretching and looks 'leggy'. What does that mean?

This is a classic sign of insufficient light. The plant is stretching its stems (a condition called etiolation) to try and reach for a light source. Moving it to a brighter spot or adding a grow light will fix this.

Do I need an expensive, professional grow light?

Not at all! For most people, a simple full-spectrum LED grow light bulb that can be screwed into any standard lamp or fixture is perfectly effective and affordable.