Whether you love it or hate it, there’s no denying that kale has become one of the most popular leafy vegetables in certain markets.
It’s also increasingly popular with gardeners because it is a leafy vegetable that thrives in cooler weather, and can even grow through the winter.
It sounds like a great option if you want to extend your gardening to a year-round activity, but what about kale’s sunlight needs? How much sun does kale need every day?
Kale needs 6 hours of direct sun to grow big in cooler weather and, so long as temperatures are low, more sun is generally better. In warmer areas, kale should be partially shaded to protect it.
Running the sun calculus for kale is pretty simple: in a cooler climate with ideal temperature ranges, more sun means bigger and better kale.
Warmer temperatures make things more challenging, and kale might need to be partially shaded to help protect it.
Your kale will always do best if you live in a colder region, but growing it isn’t out of the question if you live someplace warm.
Either way, I’ll tell you how to make sure you give your kale enough sun in the rest of this article.
Is Full Sun Best for Kale?
Yes, so long as it is in a cooler climate. Kale does great with more sun in cool or cold weather, but when temperatures rise, less sun is better to prevent damage (and it might need to be partially or fully shaded in the afternoon).
How Many Hours of Sun a Day is Best for Kale?
Again, assuming that kale is growing in an ideal climate more sun means bigger, better kale with no upper limit to how much sun it can get. 6 hours is the minimum it needs, however.
Will Too Much Sun Hurt Kale?
Once again, so long as kale is growing in a cool or cold environment, it will love all the sun that it can get.
Problems start to arise when the temperature rises, and warm weather can cause challenges for kale, and hot weather can be very problematic indeed.
This is because kale will bolt when it gets too hot, and that is why rising temperatures combined with full sun can ruin your crop.
Once your kale goes to seed, the plant really isn’t edible anymore, even when harvested early.
Accordingly, you must be prepared to protect your kale plants if you’re in a warmer climate or if you’re going through a warm spell.
Good options include companion plantings of taller plants that can shade them or using mesh canopies.
If temperatures aren’t too warm, you might consider more frequent watering to help cool the plants off directly and keep them a little cooler by moistening the soil.
Does Kale Do Well in Indirect Sun?
Yes. Assuming it doesn’t get too hot kale is a surprisingly hardy and tolerant plant when it comes to light conditions.
If you are planning on starting your kale indoors, all you’ll need to do is keep the containers near a window that allows at least 6 hours of sunlight every day…
But, if this isn’t possible or is inconvenient, you can give kale everything it needs using typical grow lighting.
Most notably, kale is edible even when it is very small if you want to partake of it while it is inside so long as it is growing, and it also tolerates transplanting quite well if you want to move it outside when the weather is more pleasant.
Just remember to make sure it gets at least 6 hours of light, and it should do well.
Will Kale Thrive in Shade?
Kale can grow when it is in shade some of the time so long as it gets at least 6 hours of sunlight at some point during the day.
Also keep in mind that your kale will be of better quality and even more bountiful the more light that it gets – so long as the weather is cool.
That being said, if you were growing kale in a warm environment, you might be best served planting it in a shady area that gets its sunshine in the morning and is shady in the afternoon.
What Will Happen to Kale That Doesn’t Get Enough Sun?
In all cases, if you see your kale leaves starting to yellow and wilt, and growth slow down, you’ll know that it isn’t getting enough light (assuming all of its other requirements are met).
When this happens, the leaves will start to turn bitter, and will get bitterer by the day meaning that even if you decide to harvest early the results are not going to be very palatable. Any kale that is severely deprived of light may die.
Additionally, kale can also go leggy when deprived of light especially after it has been experiencing dependable growth prior to.
“Leggy” means the leaves begin to grow very tall and thin, quite literally stretching upward to try and access more light.
Kale that has gone leggy is rarely going to be very productive and usually doesn’t taste good, so you can consider that another failure if you’re harvesting kale for yourself.
However, if you notice legginess very early it is possible to halt it by getting more light on to the plant or moving it if possible.
Sun Requirements for Different Kale Varieties
Different varieties of kale can have significantly different sunshine demands. Curly kale, for instance, generally wants full sun all the time. Lacinato kale, by contrast, is far more tolerant of shade for much longer.
There are many varieties of kale out in the world, some that are more tolerant of warmer temperatures than others, but one easy rule of thumb is to look at how dark the leaves of a given cultivar are.
Darker leaves generally mean that the plant can get by with less sunlight. Light or pale colored leaves need more sun.
This is because that darker coloration indicates higher concentrations of chlorophyll that can provide more benefit for the plant with less light overall.
Another good rule of thumb is to remember that if you have a type of kale that is optimized for cool or cold weather, you can confidently give it more sun more often, and the opposite is true for kale that is intended for warmer climates; if in doubt, give them less sun.
Tips for Bringing Indoor Kale Outside
You shouldn’t have any problems starting or growing kale indoors so long as it gets enough light, and doesn’t get too hot.
But if you want to move your kale outdoors or transplant it outdoors remember to harden it off by placing it in a shady spot for a couple of hours each day- prior to bringing it back in.
Repeat this process, increasing the amount of time you leave it outdoors slightly, for a week or perhaps two, and then it will be ready to live outside all the time.
Tom has lived and worked on farms and homesteads from the Carolinas to Kentucky and beyond. He is passionate about helping people prepare for tough times by embracing lifestyles of self-sufficiency.