Seed Starting Archives | Happy Leaf LED

Maximizing Plant Growth: South Facing Windows vs. Grow Lights

Are you really giving your plants the best possible environment with a south facing window? We sometimes hear gardeners talk about the success they have starting plants in a south facing window, or how they can keep some plants happy in the winter just using a south facing window. What comes to mind for us, as a grow light manufacturer, is that we hope you will consider that even the loveliest south facing window is not giving your plants the best possible environment for growth and survival. Even if the window is not covered in a coating that blocks sunlight, winter days are still much too short to provide the ideal amount of daily light most plants need.

The Limitations of South Facing Windows

If you happen to have an ideal-sized window that faces true south, then you’re pretty lucky because it is possible to have some level of success with keeping plants alive or starting seeds. While some folks are happy with the results they get from a south facing window, anyone who has decided to take a leap and try a really great grow light, will tell you there is definitely a real bonus for your plants if you pick the right grow light.

Understanding Daily Light Integral (DLI)

We all know plants need sufficient amounts of light to grow robustly. The word “sufficient” is very important here. I am going to mention one technical term and I promise this will be the only one. Plants need their daily dose of light and the technical term for this is Daily Light Integral or DLI. It is the average intensity of the light multiplied by the total number of hours of light that the plants are getting. For example, lettuce, herbs, and microgreens need a DLI of 3 to 5 per day whereas tomatoes and peppers may need a DLI of 10 to 15 per day.

By the way, the units for DLI are moles of photons per square meter per day for those of you who are curious. That is all we will say about DLI but I think you get the point that what really counts is the amount of light our plants get each day.

Challenges of Winter Sunlight

South Facing Windows : Grow Lights vs. Sunlight 1

The challenge for those of us living in the northern half of the US is that the days get pretty short in the winter (i.e. 6 to 8 hours of reasonable sunshine) and that many of the days in the winter are cloudy or overcast. So we may only be getting on average 4 to 6 hours of sunlight per day.

On top of that, the windows we all have in our homes have special coatings on them to improve their ability to insulate from the cold and to reduce the amount of light entering our homes in the summer to reduce our air conditioning cost. These coatings are called low emissivity or Low E coatings. These coatings block about 75% of the light from the sun.

Add these factors together and it turns out that we are lucky if we can get enough light through our windows to keep our plants alive and maybe grow some microgreens. If we were hoping to grow plentiful amounts of greens, herbs, or possibly some cucumbers or tomatoes, we will most likely be disappointed.

Optimal Growth Solutions with Happy Leaf LEDs

High quality grow lights that use very efficient LEDs will enable you to grow pretty much any plants you would like quickly and efficiently for just pennies a day. They use the proper ratio of red to blue to green light as well as the right intensity for growing everything from arugula to tomatoes. Turn on your light that can be in your basement, closet, or kitchen for 14 to 18 hours per day and you will be amazed at your winter bounty.

Click here for a deep-dive into what you need to know about grow lights.

And that brings us to flexibility. With Happy Leaf LEDs, you won’t have to locate ALL OF YOUR PLANTS IN ONE WINDOW…. or, only in south facing windows…. or, in any windows at all. You can grow herbs on a shelf in your kitchen, lettuce in your living room and tomatoes in your basement! No windows (north, south, east or west) required.

A 33 inch Procyon 2.0 Happy Leaf light can grow an area of up to 2 x 4 feet for your greens, herbs, and microgreens. You will be eating your harvest within 4 weeks of your planting date.

We encourage you to give it a try and we guarantee you will become as addicted as we are to winter indoor gardening.

Still on the fence about starting your indoor gardening adventure? Get inspired by our YouTube channel or browse our blog posts for answers to your technical grow light & indoor gardening questions like ‘Grow Lights – How Much Should I Pay?‘ or what are some unique varieties I can grow?

Happy Leaf LED is a proud member of The National Garden Bureau.

Seed Starting. Image of young woman holding broccoli in her hands

It’s Not Too Late for Seed Starting. Get Your Grow On!

It’s early May and you may be thinking… There is no way I can start plants now!

Maybe you got anxious to plant outside (no judgement – who isn’t?) and your veggies got hit with frost. Maybe you couldn’t make it to the garden center in time, and they were all sold out. Or, just maybe, you didn’t have a chance to plant seeds earlier in the season. No reason to fret though because there is still time to start several seed varieties indoors that will let you enjoy harvest o’plenty later in the season. There are lots of vegetable plants that can still be started indoors for later planting outside.

So get ready for a great list of plants to start now! If you’d like a little refresher, watch our in-depth seed starting video here.

While it may seem counterintuitive to start seeds this late, the trick to helping the seedlings grow faster is using grow lights. Now, on to thinking about what to consider when making your choice about which plants to start now so you can enjoy a bounty of vegetables outside, even if you had a late start.

Brassica is Fantastica!

Members of the Brassica family are excellent choices because the plants germinate in less than a week and are ready to transplant in a few short weeks. These crops include:

Broccoli
Cabbage (Red and Green)
Kale
Kohlrabi
Brussel Sprouts
Cauliflower

The @wisconsinvegetablegardeners has a fantastic video on starting brassicas indoors!

Succession Crops

Those are crops that can be planted every 10-14 days to spread out the harvest by giving you several small crops instead of harvesting them all at once. These plants traditionally include:

Radish
Peas
Kale
Spinach
Lettuce
Beans
Carrots
Beets
Turnips
Onion
Chard
Collards

Plants with Fast Germination

Another option for plants to start now are the ones that have a fast germination. Many of these are ones that can also be planted by direct sowing them into the garden. However, the number of days to be ready for transplant is generally shorter under Happy Leaf grow lights, so you can speed up the process by getting a jump start indoors. These crops include:

Corn
Cucumber
Summer Squash
Winter Squash
Pumpkin
Cantaloupe
Watermelon

Other Plant Varieties

Even if you prefer plants like for instance tomatoes or peppers that typically have a longer germination and transplant time, it’s not too late to start those in your house now. There are varieties that have been bred to be smaller and therefore do well in containers. So, if they aren’t ready to harvest before the fall killing frost, you can always bring the container inside and place under your grow lights to finish them relatively quickly. Give some of the following a try:

Eggplant ‘Patio Baby’
Cucumber ‘Spacemaster’
Tomato ‘Tumbling Tom’
Tomato ‘Tiny Tim’
Tomato ‘Spring Giant’
Pepper ‘Jalapeno’
Pepper ‘Habanero’
Pepper ‘Keystone Resistant Giant’

Plants That Have Short Crop Cycles

There is still time to start some varieties of tomatoes and peppers that have a comparatively short crop cycle. You will find that information on the seed packet as “Days to Harvest”. A typical tomato takes about 70 days, some longer. Try the following ones that mature relatively quickly:

Tomato ‘Early Girl’ – it matures in just 50 days after planting.
Pepper ‘Mountaineer Sweet Pepper’ – delicious pepper variety that is ready quickly and bears good yields, ready in only 53 days to green or 68 days to red peppers.

There are lots of plants that are ready more quickly than their “typical” counterparts. There is still time to sow any of those that have a “Days to Harvest” time of around 65 days or shorter.

Other Considerations

Notice that lettuce and herbs do not appear in any of these lists. Although there is still time to sow them in your outdoor garden, I simply find them so easy and foolproof to grow indoors that I haven’t grown them outside in several years. They stay disease and insect free, do not bolt, give you several crops when in an indoor controlled environment, and are unnecessary to wash. Best of all? It frees up space for some of your other favorite outdoor crops that need more room to grow.

Ready To Grow? I Know We Are…!

Now it’s decision time: Which seeds to pick? Which plants to start now? Only you know the answer. But here’s what we recommend: Get your pots and growing medium ready and let us know what you decided to grow – we’d love to hear from you! Get your grow on!

Interested in the technical aspects of all things grow light related? Click here!

Procyon 2.0 Full Spectrum LED Grow Lights

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