Sunlight vs Grow Lights

I’ve done a lot of home gardening over the years and always did well without grow lights. Our home had plenty of southwest facing windows and because we live in sunny Alberta, I was able to successfully start many seedlings indoors.

However, the best method for strong, sturdy plants is to use grow lights, especially if you live in a cloudy area or if your home does not provide enough sunlight (at least 6 hours per day). So, to be on the safe side, investing in grow lights will ensure your seedlings are off to a great start!

Sowing seedlings indoors is how I get through those last wintery weeks before spring truly settles in Alberta. Seeing tender, new greens is very uplifting!

Below, I’ll share information on both methods. The most important thing to remember is that all seedlings need warmth and many hours of light per day to grow!

The easiest seedlings I grew on the windowsill were lettuce, kale, Swiss chard, green onions, cucumbers and cherry tomatoes.

These were the simple rules I followed:

1.       Firstly, making sure to have a nice sunny spot outdoors to plant seedlings once they’re ready. Most plants need 6 to 8 hours of sunlight per day.

2.       Use good quality seedling soil to start seeds.

3.       Take note on a calendar when seeds should be sown, timing is vital. Check the packet for sowing dates and how deep to plant the seeds. Not every seedling takes the same time to grow before being planted outdoors, this could be anywhere from 4 to 10 weeks, and sometimes longer!

4.       Ensure seedlings are getting enough light from a southwest facing window (about 6-8 hours). At night move seedlings to a warm area, as it can get cold around windows in northern climates.

5.       Keep soil moist without overwatering.

6.       Harden off seeds adequately before planting outdoors after last frost.

Our current house does not provide enough continual light to grow seedlings as I used to. Also, I no longer grow vegetables and flowers as a simple hobby, therefore grow lights have become a necessity.

Firstly, a shelving unit will be required. I found these sturdy shelving units on wheels at Costco. They also have them at Canadian Tire and Home Depot. But you can use any shelving you prefer, as long as hooks can be installed to hang grow lights.

Grow lights can be found in most hardware stores or ordered online. They usually come with an adjustable chain or wire to easily hang and adjust them as plants grow.

Most plants don’t need light to germinate, but once they’ve began poking their first leaves through the soil, they’ll need about 14-16 hours of artificial light per day. The intensity of light provided by fluorescent and LED bulbs can be dramatically different; be sure to follow the brand’s recommendations on the distance to hang them above plants to ensure your seedlings are getting the right amount of light. Remember to turn off lights at the end of the day, as plants need darkness to rest, just like we do!

If you’re growing area is in a basement or a cooler spot, heating pads are a must to warm the soil, as most plants need heat to germinate.

I’m currently using a sunny space inside my home and am controlling the temperature to about 22°C during the day and 18°C at night. The grow lights are also providing a bit of warmth.

Using a fan on the lowest setting is also very helpful to keep the air circulating. By doing so, plants will be less prone to disease, such as damping off, which will kill seedlings. Therefore, keeping good airflow will discourage the growth of fungus, mold and algae which can result if the soil remains wet for long periods of time.  

While it’s important to keep the soil of seedlings moist, when watering, add water a little at a time to avoid soggy soil or plants sitting in water for days.

Happy gardening!