Why is my broccoli plant growing too tall?

Have you ever been growing broccoli in your garden and had it grow taller than you expected? You’re not alone! broccoli plants can get quite tall, but there are a few things you can do to keep them under control. In this post, we’ll discuss the reasons why broccoli plants grow tall and give you some tips on how to manage their height.

Power-packed with nutrients, broccoli is also known as the ‘Crown jewel of nutrition’. More and more Americans now are preferring to organically grow their own broccolis in their garden rather than buying broccolis from the store or supermarket and for obvious reasons, it is always a better idea to go for safe and naturally grown organic vegetables.

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With all the benefits of growing broccoli organically at home, there also come a bunch of questions and problems related to it. After all, broccoli might be a bit tricky vegetable to grow by yourself.

One of the many problems people that people face while growing their broccoli plant at home is why is their broccoli plant growing so tall, and is it a good sign or a bad sign?

Why is my broccoli plant growing too tall?

Well, you might initially feel that your broccoli plant growing tall is a good sign and is a sign of healthy growth of your plant, but then realize that it is not producing healthy, green broccoli heads or not producing any broccoli heads at all!

This could happen in situations where your broccoli plant is growing too tall as a result of stress!!

Broccolis usually grow up to a height of two and a half feet. If you find your broccoli plant is growing way too taller than this, then here are some reasons you can look into.

1. Are you sowing a lot of seeds at a time?

The first and foremost thing that you would want to keep in mind while starting sowing your broccoli seeds is to make sure that you don’t end up overcrowding the unit in which you are sowing the seeds.

As already discussed, broccoli plants grow upwards and not outwards so when you overcrowd the broccoli plants and start to grow them very close to each other, then they would start competing for space and thus will end up growing extremely high or tall.

The most common reason why your broccoli plant is growing too tall could be because it is starting to bolt. Bolting is the process in which the plant starts to produce flowering stem to produce seeds before the crop is harvested, in order to complete its reproductive cycle. Bolting is a survival mechanism and it usually takes place under conditions of stress.

So in other words, broccoli plants can grow very tall due to stressful conditions, such as extreme weather or extreme soil temperature, etc, which are eventually causing your plant to bolt.

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2. Overcrowding your broccoli plants

When you are transplanting your broccoli seedlings into the garden bed or the larger area, it is extremely important to make sure that you are spacing each broccoli plant correctly.

If you don’t sow them at an adequate distance from each other, then this can result in your broccoli plants growing taller than they are supposed to be.

This is because broccoli grows into huge plants and needs a good amount of space for a single plant, so if they are improperly spaced then they will start competing for nutrients and space does make them grow taller in height.

Overcrowing your broccolis can also lead to the production of unhealthy broccoli heads as your plants are not getting sufficient nutrition for their growth.

It is important to take care that you place each broccoli plant at about a distance of 10 to 20 inches apart from each other. Also, ensure that you dig holes that are at least 4 to 6 inches deep for transplanting the plant into the bigger container.

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3. Your broccoli plant has aged

Once the broccoli plant has reached its maturity, it will start to bolt, that is, it will start to go into flower. It is during this time that your broccoli plant will increase in size and grow very tall. It is also at this point that your broccoli becomes bitter and thus, is not a good option for consumption.

There are some signs that you can look into in order to figure out if your broccoli plant is starting to mature and is about to bolt. Mature broccoli starts to become yellow and pale green in color.

It is at this time that the vibrant dark green color of your broccoli head starts to fade away for a paler green and yellowish color. If you see any signs of yellowness in your broccoli head, then immediately harvest it without wasting any further time.

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4. Too much heat

Broccoli grows the best when the temperature range is between 18°C to 21°C (or 65°F to 70°F). Broccoli plants cannot survive in temperatures below 10° C or 50° F.

Similarly, this cool-season crop can also not tolerate a lot of heat and if the temperature exceeds the ideal range of temperature tremendously, then this can cause your broccoli plant to bolt which might result in your plant growing really tall.

If you frequently grow broccoli in your garden then you must have noticed that they grow better in the cooler time of the year and usually don’t grow that well in hot and dry conditions. This is because, broccoli is a cool-season crop and thus, it grows best in cooler conditions and colder times of the year.

However when the temperature exceeds the optimum temperature range then your broccoli plant will start to bolt to prepare for the production of seeds for the next generation which is actually a survival mechanism for the broccoli plant. This will result in your broccoli plant growing quickly and growing taller than its expected height.

If you are growing your broccoli plant during the hotter time of the year, then it will be a good idea to place your broccoli plant in a semi-shaded place in order to avoid overexposure of your plant to strong sunlight.

Yet another way to deal with the hot climate would be to practice mulching. Mulching is the process of applying a layer of organic or inorganic material over the soil, which will act as a protective layer.

This extra added layer over the surface of the soil will help to keep the soil in the deeper layer cool and eventually will also help keep the roots of your broccoli plant cooler and thus not get affected by the hot climatic condition.

Apart from this, mulching also helps in improving the fertility of your soil and helps in the retention of soil moisture.

Another way to keep your broccoli plants cool is to water them a bit more frequently, but remember not to overdo it as overwatering can cut off the oxygen supply to the roots as a result of which the plant might not be able to survive.

There are certain heat-tolerant varieties of broccoli that you can grow, such as – Gypsy, Green Magic, Sun King broccoli, etc, depending on its availability in your area.

The ‘Green Magic’ broccoli is a variety of broccoli that is able to adapt to a wide range of temperatures, and the ‘Sun King’ broccoli is one such variety that is specially bred for being able to grow in the hot summers of Southern California

You can always choose to grow the variety of broccoli that suits best the climatic conditions of your place.

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5. Too much strong sunlight

Sunlight is one of the main factors that decide and contribute to the healthy growth of your broccoli plant. Broccoli, just like other green vegetables, requires a good amount of sunlight for its healthy growth.

A minimum of 6 to 7 hours of sunlight daily is necessary if you want your broccoli plant to produce healthy and green broccoli heads. However, too much strong sunlight and overexposure of your broccoli plant to the Sun can actually cause stress and thus lead to bolting.

As already discussed, bolting is the process in which your broccoli plant will try to quickly complete its reproductive cycle under stressful conditions to ensure its survival. So in such situations, your plant will try to quickly transition from its different phases and therefore grow taller very quickly without being able to produce healthy broccoli heads.

One of the ways you can prevent your broccoli plants from overexposure to sunlight is by shifting them to a semi-shaded place if possible.

If you have planted rows of broccoli plants in your garden then you can also use row covers for your plants. Row covers will not only protect your broccoli from the extreme heat and strong Sunlight but also will help the soil to remain cool.

An added benefit of using row covers is that it will help to keep pests and insects at bay and thus help to prevent your broccoli plants from being attacked by pests.

Why is my broccoli plant growing too tall
Why is my broccoli plant growing too tall

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If your broccoli plant is growing way above two and a half feet in height and you are noticing that it is not producing healthy broccoli heads, then it is a sign for you to be cautious.

The most common cause for your broccoli growing too tall is bolting, which happens as a result of your broccoli plant going through stressful conditions such as extreme heat, strong sunlight, etc.

In order to prevent your broccoli plant from growing too tall, it is important to ensure that you are providing them with optimum conditions for their growth and taking necessary precautions against bolting, such as using row covers for your broccoli plants. Just keep these few points in mind while growing your broccoli plant and you will get the best results!

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