The holidays are here again. This year of Covid has been a hard year for…
Planning to grow plants indoors? Whether you are planning on growing traditional house plants, caucus or vegetables one of the most important things is to know how to choose the best grow light for indoor gardening.
The first thing you need to do in understand the basics of what light is.
Let’s take a general look for non-scientists.
The light that we see is a merging of all the colors of the rainbow. This means that white light can be split into colors. If you have ever looked at light through a crystal than you know just what I mean.
A rainbow is a demonstration of the same principles.
Why is this important to know when choosing the best grow light for an indoor garden?
Your plants need certain colors of the rainbow to grow.
Plants use the light emitted from the blue spectrum to grow green lush foliage.
They use light from the red end of the spectrum to grow fruits.
So if you are growing things like house plants you should be more concerned about giving your plants blue spectrum light.
For vegetables and flowers, you need to think red.
But how do I know what kind of light I am buying?
Every light sold comes with a standard label
Learning to read these labels correctly can ensure your plants get the right kind of light.
Lumens vs Kelvins
Lumens is the brightness of the bulb. The typical 60-watt incandescent bulb is 800 lumens. While a 100-watt incandescent bulb is 1600 lumen.
Kelvins indicates what color the light is. DON’T be confused by the term color on the Kelvin chart. Lights will still appear white to your eye! Our eyes are not able to distinguish light color spectrum however your plants can.
The terms lumens and Kelvins are not actually related. It does seem odd but you can have a bulb that is higher in lumens and lower on the Kelvin scale and the other way around.
There is no lumen to Kelvin’s calculator or conversion chart. A warmer or high kelvin number may seem brighter because of how our eyes interpret light but there is no relation between the numbers. A great more in-depth explanation of lumens and Kelvins read earthLED
I like to think of lumens and Kelvins in simple terms. Lumen is how bright we see the light while Kelvins is how a plant sees the light.
In other words, a really bright light isn’t automatically good for your plants.
The light that is best for your plants is dependent on what you are trying to accomplish.
When starting seeds the best light for your plants is on the blue side of the scale
This means that you need to have a light that has a kelvin spectrum around 5000k -6500k. Plants use this end of the spectrum to grow stems and leaves. Giving your seedling easy and plentiful access to blue light will help them grow bigger and stronger.
To grow more flowers and fruits choose red light
When your plants are grown and it’s time to start producing flowers and fruits the best grow light for your indoor gardening goals will be in the lowest kelvin range. A 2700k to 3000k will give your plants the energy they need to produce fruit.
There are white grow lights available on both end of the spectrum. The best grow light for indoor gardening will change as your plants and your goals change.
Are blue and red lights the best grow lights for indoor gardening?
I like the red and blue lights. They are simple to use because regardless of what your goals for your indoor gardening are, they will provide the right kelvin. You can set up a light and be assured that your plants will always get their light needs fulfilled.
There are many varieties of these color lights available. The main thing you need to know is that at night the light will appear colored. They give off a colorful glow to your room. Some people may not appreciate the colors. It is a personal choice.
Having a mix of both types of lights can be a helpful way to manage your indoor garden.
What lights are NOT the best grow lights for your indoor gardening?
- Never choose a grow light based on its lumen number or brightness. Remember that brightness is not something that your plants care about. A really bright light in a 4500-kelvin range is not nearly as helpful to your plants as a light with a lower lumen number in the right color range.
- Don’t try to get a light that will hit both ends of the spectrum by purchasing a light in the 4000k range. Unfortunately, you can not find the center to satisfy both ends. What will happen is that you will not be helping either the foliage or fruiting.
The distance from the grow light to your garden matters also
Different types of lights have different effective ranges.
An incandescent light will be effective only if your plants are very close to the light. However, with incandescent bulbs, there is a problem. Incandescent bulbs give off a lot of heat. This heat can burn your plants. So never put an incandescent bulb closer than 24″ from your plants. These bulbs are not the best grow lights for indoor gardening because of this problem.
Fluorescent grow lights are a better choice. They give off just a small amount of heat. These bulbs typically come in long lengths so setting them up over a shelf or window is easy. The light does disperse quickly so they are most effective within 12″ of your garden.
LED grow lights may be the best choice. These lights can be placed as close as a couple of inches from your plants up to 36″ from the top of the leaves. The distance will depend on the wattage of the light. In general the higher the watts the farther you can go.
LED grow lights allow a lot more flexibility in setting up your indoor gardening space.
The best light set up for your indoor garden
The best thing to do both to save money on your energy bill and to ensure that your plants are happy is to set up your garden in a sunny window.
You can see in the pictures above that the sun hits the carrot garden for a time then the grow lights take over.
Your plants will need 10 hours plus or minus of light each day. The grow light goes on when the sun leaves the window. Using natural light and grow lights together ensures enough hours of light and a lower electric bill.
What about the cost to run grow lights?
All lighting packages include the information as seen above. The packages also include the cost of running the light.
These graphics are a great way to determine how much your grow lighting will cost you.
Knowing the best type of light, knowing the cost and using grow lights with natural light all will lead to a great indoor garden without a huge expense.
For more about how to set up an indoor garden please check out Setting up an indoor garden
Thank you for reading.