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Why Are My Cabbage Plants So Tall – Factors To Consider!

When growing cabbage, one scenario you might encounter is that your cabbage has grown tall with large leaves, but it does not seem to be forming a head. Anytime you get leggy cabbage plants like that it’s a cause of concern. You may wonder; why are my cabbage plants growing so tall?

Cabbage plants grow tall when they lack space to grow. This encourages the plant to grow vertically rather than spreading out. Also too high of soil temperatures and excess fertilizer can cause plants to grow too tall.

Even though cabbages can end up growing tall from mistakes we make as gardeners, sometime those mistakes can lead to other issues with the plant. We’ll dive into all of those next as well as a typical growth chart for your cabbage plants.

Cabbage Plant Growth By Month

Cabbage can get much taller than you think. Before we get into all the reasons why this happens, let’s take l look at a typical growth chart for most cabbage plants. This table includes data from seed all the way to 5 months of growth.

a few weeks old (seeds)not visible above the ground level
1 months oldaround 3 inches tall
3 months old4-8 inches tall
5 months oldfull grown, around 12-14 inches tall
Cabbage height in inches growth chart

Reasons Why Cabbage Plants May Or May Not Grow Tall

Many factors, everything from the soil to the temperature outside, can contribute to your cabbage growing in that way. 

Your cabbage was grown at the wrong time of year. 

Cabbage does not thrive during the warmer months of the year and is considered a cool-season vegetable. To have a successful harvest, plant later in the year. You want to plant your cabbage about eight weeks before you typically would experience the first frost of the year.

This provides your cabbage with optimal growing conditions and will prevent it from growing in a nontraditional way. Additionally, cabbage planted during the year’s cooler months is typically sweeter and tastier overall!

The soil was not the right pH balance for optimal cabbage growing conditions. 

For cabbage to grow successfully, it requires a specific type of soil. Ideally, you would want your soil to have a pH balance of 6.5 to 6.8 for optimal cabbage growth. If your cabbage is planted in the soil outside of that range, it can lead to an underperforming plant that may also develop diseases. 

You forgot to fertilize your cabbage. 

While fertilizer is not always essential for growing cabbage, it makes a huge difference in helping your plants grow strong and healthy. Just as humans are recommended to take vitamins to help with any potential deficiencies, fertilizer acts the same way for cabbage plants to ensure they are growing with the optimal nutrients.

A key nutrient missing from the soil can lead to a cabbage plant growing incorrectly. 

You grow your cabbage from bad or defective seeds. 

It is possible that your cabbage grew incorrectly because the cabbage seeds were just simply not good. While this is less common than some other ailments that can cause your plant to grow incorrectly, occasionally, you will encounter seeds that were never going to grow correctly. 

This can happen when seeds are too old or exposed to harsh elements, such as extreme temperatures or radiation. Seeds can also have genetic defects that prevent them from germinating. This can be a letdown, but make sure to purchase your seeds from a reputable nursery or plant shop to avoid encountering this issue moving forward. 

Your cabbage was damaged while it was growing. 

Plants can be damaged in a lot of different ways during their maturation. Whether your plant suffered from too much stress, was attacked by bugs, or was scalded by the sun, all of these scenarios lead to less than ideal growing conditions for your cabbage.

Often, if damage does occur, you will notice the plant is growing incorrectly or begins to look like it is going to die. The good news is that sometimes damaged plants can be saved with proper care! 

The first step is to get to the cause of your plant’s damage and try to begin by treating the issue. Sometimes they may mean relocating your plant or adjusting the amount of sun or water it receives daily.

You may be able to cut off the damaged part of the plant to preserve the energy for the rest of the plant. Feeding your plant fertilizer is often another good boost for the plant to help it get back on track. 

Your cabbage is bolting. 

While you may never have heard of the term bolting before, it is something pretty common that can occur while gardening. That means your plant produces a flower stalk instead of forming a head, which essentially means your cabbage plant did not grow correctly.

This often can be caused by a unique combination of weather conditions, such as when the temperature is too hot for the cabbage and then drops into cooler temps.

Those sudden fluctuations can cause your cabbage to grow too tall without producing the cabbage head you were hoping to see! While this can be frustrating, there is always some unpredictability when growing plants outside. Certain crops will always be better than others.

Your cabbage was planted somewhere too dark. 

If your cabbage plants grew very tall, there is a chance that it was planted in a space too dark for the cabbage plant to grow properly. There is always a chance that you can revive a plant that has started growing incorrectly before the end of the cabbage growing cycle.

Try to replant the cabbage or move it to a spot where the cabbage will get the correct amount of light. While it’s never guaranteed that this will fix your cabbage plant, it is worth trying out! 

The nitrogen in the soil was off. 

For a cabbage plant to grow successfully, it needs the proper amount of nitrogen. Soil should be composed of 50% carbon or 5% nitrogen to grow correctly. When incorrect levels of nitrogen are present in the soil, the plant often experiences a decrease in growth levels and eventually will begin to decompose.