Kale is a superfood that’s super easy to grow in your garden. It grows even during cool weather, so you’ll have a food source well into the frostier months. However, your kale can grow too tall, making it susceptible to damage and disease, or cause it to produce bitter leaves you don’t want in your salads or smoothies — so you have to figure out whether it’s too tall for its own good.
Here are five ways to know if kale is growing too tall:
- The kale is over 36 inches (91 cm) tall, depending on type.
- The kale has a long, skinny appearance.
- The kale is bolting.
- The kale plants grow too close together.
- The kale isn’t being harvested often enough.
Read on to learn more about the above signs so you’ll know what actions to take to remedy the situation.
1. The Kale Is Over 36 Inches (91 cm) Tall, Depending on Type
There are many varieties of kale, and some can grow as tall as four feet (122 cm). But the vast majority of kale shouldn’t grow that tall. For example:
- Chinese kale grows 18 to 20 inches (46 to 51 cm).
- Common curly kale might get as tall as three feet (91 cm).
- Dinosaur kale consistently reaches heights of 32 to 36 inches (81 to 91 cm).
- Ornamental kale (also called salad savoy) barely clears one foot and might reach 15 inches (38 cm) tops.
- Red Russian kale is a larger variety, usually topping out at three feet (91 cm) or more.
- Siberian kale, like its red Russian cousin, can reach three feet (91 cm).
Knowing what kind of kale you have in your garden will arm you with the knowledge of how tall it should get. If you’ve got a salad savoy plant as tall as you are, you can be pretty sure it’s grown too tall.
2. The Kale Has a Long, Skinny Appearance
With their frilly leaves and rich color, kale plants should appear full and have an almost fluffy look to them. So if your kale plant has grown tall and skinny, it’s probably gotten too tall. When kale grows too tall too fast, the plant loses its width and appears somewhat emaciated.
No matter what variety you have — even if it’s the rare kale plant that’s supposed to reach three feet (91 cm) — if it’s skinny, it’s too tall or has grown too quickly.
3. The Kale Is Bolting
Kale, being a cool-weather plant, is especially prone to bolting (a.k.a. “going to seed”). Bolting is when a plant starts to produce seeds too early. It’s essentially a defense mechanism, and kale employs it (usually) when it gets too hot.
Now, it’s not that you don’t want seeds. You need them, after all, to grow more kale. But ideally, kale shouldn’t produce seeds until its second season.
When kale begins producing seeds, it stops putting effort and resources into growing leaves. That means you’ll have fewer leaves to harvest from the plant, and the leaves you get will be bitter. They won’t make you sick if you eat them, but they won’t taste good either.
If a biennial kale plant, in its first season, gets the idea that things aren’t going well for itself, it will prematurely shift to its second-season job: making seeds. This shift usually happens when the weather gets too hot for the plant.
When the kale plant bolts, it’ll start producing shoots with seed florets, and they’ll tower over the rest of the plant. While the florets are edible, they’re an indication (at least in the plant’s first year) that it’s bolting.
So if you see tall stalks with tiny flowers on them, your kale is bolting, and it’s also a sign that it’s grown too tall.
4. The Kale Plants Grow Too Close Together
Like all living things, kale grows to fit its space. Ideally, when planting from seeds, you want to space your kale about 18 inches (46 cm) apart in their rows, with each row about two feet (61 cm) apart. With room to grow, the plant can spread out a little, and you’ll have some space to get in there and harvest some leaves.
If your kale is too close together, though, it’ll grow where it needs to as it seeks out nutrients, and that’s most likely going to be up. If you’ve planted your kale too close together, it’ll grow taller than it would if it had more horizontal space.
In this case, taller kale isn’t necessarily bad, but the plant is more likely to get damaged by high winds. Also, the closer your plants are to each other, the more susceptible they’ll be to fungal and bacterial infections. Fungi can take root anywhere, and they’ll spread much more quickly to other plants if your kale is too close together.
5. The Kale Isn’t Being Harvested Often Enough
If you want to know whether your kale is ready for harvesting, pick their leaves from the outside in. When they’re about the size of your hand, that means they’re ready to harvest. But if you harvest, say, all the kale leaves at the bottom of the plant, your kale will direct its resources into growing taller to grab as much sunlight as possible.
When it comes to kale, you shouldn’t harvest leaves that aren’t ready. Also, don’t leave a harvestable leaf on the plant just because it’s not close to the bottom of its structure.
If you don’t harvest your kale often enough, the mature leaves begin to turn yellow or brown and wither. Since the leaves function roughly like the kale’s solar panels, when they brown and die off, the plant is forced to make new ones and may try regrowing them higher up on the stalk. The result? Too-tall kale.
What To Do When Your Kale Gets Too Tall
The best way to deal with too-tall kale depends on the cause. If it’s due to bolting, there’s not much you can do to stop it, though you can mitigate it somewhat. Otherwise, you may still be able to save your kale and make sure it stays in good shape.
When Your Kale Gets Too Tall Due to Bolting
If you notice your kale plant is bolting, you’re essentially on the clock, as there’s no way to stop it from happening. You can only make the most of the time you have left, as the plant will eventually stop producing leaves that taste good.
If your kale is bolting, here’s how you can salvage your plant (assuming you still intend to use it and not throw it away):
- Harvest as many leaves as you can, and do it the moment they’re ready.
- If the leaves from your bolting kale plant are bitter, massage them before eating them (really!).
- Nip off the flower buds.
- Focus on eating the florets, which are quite tasty and will come in more and more as you nip off the flower buds.
When Your Kale Gets Too Tall for Reasons Other Than Bolting
If your kale has grown too tall and it’s not due to bolting, you always have the pruning option. A top-notch gardening tool like the Fiskars Bypass Pruning Shears (available on Amazon.com) makes easy work of this process. The shears aren’t only sharp: They’ll last you long enough to deal with any other pesky plant problems you may encounter in the future.
To prune too-tall kale, here’s what you need to do:
- Snip off any tall, flowering stalks as close to the stem as you can.
- If the whole plant is overgrown, apply the shears to the central stalk, about five inches (13 cm) above the ground.
- Wait for about a week, and you’ll see baby leaves sprouting. They should be delicious and are a good sign your kale plant is roaring back into action.
Proper care and harvesting will ensure your kale grows like it’s supposed to, but it can grow too tall.
Here are the signs your kale may need to be cut down to size:
- It’s more than three feet (91 cm) tall.
- It’s skinnier than normal.
- It’s bolting.
- The plants are too close together.
- You’re not harvesting the kale often enough.
Keeping an eye on your kale and harvesting it often will help ensure you have these lovely greens on your plate well into the winter.