pests in garden, broccoli with broken leavesBroccoli leaves turning yellow is quite a common problem and might be caused by several reasons such as nitrogen deficiency or fungal diseases. With a little watchfulness, you can find a quick resolution to this.

In this article, we discuss the issue in detail and provide the most effective solution. Read on to understand why your broccoli turns yellow and what you can do about it.

Why Is My Broccoli Plant Turning Yellow?

Maturity, nitrogen deficiency, or pests and diseases are some of the various reasons why a broccoli plant may be turning yellow. Let us inspect each of these aspects separately so that we can resolve the crisis once and for all.

– Maturity of the Plant

If your broccoli remains un-harvested, slowly yet steadily you will find the tiny florets on the head of the plant turning yellow. This is a natural process in which a mature flower bud swells to produce seeds. At this stage, some yellowing is bound to occur.

Although this is normal, take note that yellowed broccoli is bitter and does not contain any nutritional value.

– Nitrogen Deficiency

Here is another very common cause for your broccoli turning yellow. A nitrogen-deficient soil can bring in yellowing broccoli. In such a situation, the plant will eventually wilt and die.

Bear in mind that broccoli plants are heavy feeders and require nitrogen-rich soil. So if you have soil that is deprived of this, the plant isn’t going to get the nourishment it requires.

– Fungal Disease

A commonly overlooked aspect of broccoli turning yellow in garden is fungal infections such as Fusarium oxysporum. The disease attacks not only the stem but spreads all over the plant. In due course of time, if left to fester, it affects the health of the plant by stunting its growth or even killing it in its entirety.

– Black Rot

If you have noticed V-shaped yellow spots on broccoli leaves, this is due to black rot. Too much heat or moisture causes black rot in these plants. It can spread all over via:

  • Infected seeds
  • Insects
  • Water splashes of rain or irrigation

Once these spots appear, they infect the veins, completely turning them black. Over time, they discharge a yellowish fluid that will make the plant wilt.

– Clubroot

Broccoli with yellow spots can be spotted if the plant has been infected with clubroot. This is a condition that causes the roots to swell up and the leaves to dry out.

The only way you can tell if the yellowing is due to clubroot is to pull out the plant and inspect the root nodules. As this is not something that can be done often, it is recommended to inspect the roots only after all other causes of yellowing have been eliminated.

– Pest Infestation

Pests such as mites, cabbage loppers, maggots, cutworms, aphids and flea beetles can infest broccoli plants, causing the leaves to turn yellow.

– Excess Sun Exposure and Lack of Water

The broccoli plant requires a cool environment. Excessive sunlight coupled with inadequate water can turn the broccoli yellow. The plant seldom thrives in harsh and direct sunlight, so under stress conditions, it can easily deteriorate.

For a healthy and bountiful yield, ensure the plant remains in an environment that it can adapt to well.

Preventing Broccoli From Yellowing

Now that you have understood the most common reasons for yellowing broccoli leaves, let us delve deeper into solving the problem. The steps we will mention below will help you tackle the situation effectively.

– In Case of Over-Maturation

Harvest the vegetables immediately. The ideal time to harvest is when the main shoot stops expanding and the flower buds turn dark green. Do not leave the broccoli unattended beyond this point as the yellowing reduces taste as well as nutrition.

– In Case of Nitrogen Deficient Soil

As discussed earlier, the broccoli plant requires rich soil. If your soil is deficient in nitrogen, you will need to add a fertilizer that has a high percentage of nitrogen. This will not only prevent the broccoli from turning yellow, but it will also guarantee you an abundance of produce.

Make sure the nitrogen-rich fertilizer that you use is low in phosphorus content. You can also do crop rotation with legumes to increase the nitrogen content in the soil.

– In Case of Fungal Disease and Black Rot

Unfortunately, there is no remedy for yellowing that is caused by fungi fusarium. The only way to tackle this is to spot them early before they cause devastation to the plant. Early detection of fungal disease will prevent its spread to other plants around as well.

If you have spotted fungal disease, isolate the affected plant right away. Try crop rotation to prevent future fungal disease and yellowing of your crop.

– In Case of Pest Infestation

Check your broccoli regularly for pests that attack leaves. Pick them out manually, carefully removing the affected leaves. The best way to prevent pest infestation is to engage in companion planting.

Plant your broccoli along with aromatic plants such as herbs, sage, dill and mint. These aromatic plants can repel insects of various sorts, keeping the broccoli safe from infestations. You can also drape a lightweight fabric directly over the broccoli plants to prevent pests from getting to them.

– In Case of Clubroot

You can reduce the impact of clubroot by removing the infected plant. Clear the earth surrounding the plant because the disease can stay trapped in the soil for ten years.

You can prevent clubroot by regulating the pH of the soil around the plant. The infection is most likely to happen if your soil is acidic. Thus, create a safe environment for your broccoli by keeping the pH levels neutral, between 6 to 7.

– Provide the Right Environment

For healthy and bountiful growth, broccoli requires a dry and cool environment. Although they are hardy plants, avoid placing them under harsh and direct sunlight. Maintain a watering schedule that keeps the soil lightly moist.

– Water Regularly

It is important to maintain the right watering routine to prevent most yellowing problems. The broccoli plant requires enough water to just keep its soil moist.

Dig down to a depth of over two inches to water at the base of the plant. If your broccoli has been planted in sandy soil, it will require frequent watering as it will drain out water faster.

– Add Some Mulch

If you wish to cut down on the time spent in watering, especially in hot weather conditions, add a layer of mulch over the soil. This helps retain the moisture intact in the soil. You can also mix compost into sandy soil to improve the retention of water.

– Organic Compost

Apart from the nitrogen-rich fertilizer, for additional nutrition use an organic compost mix for your broccoli crop. Dig two to four inches deep in the soil and place a layer of compost.

An example of organic compost that you can use is rabbit manure. You can also choose to plant broccoli after a legume crop such as peas to keep the soil nourished.

 

Is It Safe To Eat a Yellow Broccoli Head?

Yes, it is safe to eat a yellow broccoli head, but it is better if you avoid it as it won’t taste good. As your broccoli head starts to turn yellow, the taste gets more and more bitter. The nutrition element decreases too and it is most likely going to give you stomach gas.

Harvest and consume the broccoli when the florets are deep green. This is when they are high in iron, calcium and vitamin K. A yellowing broccoli isn’t necessarily rotting, but is simply wilting and deteriorating.

How To Keep Broccoli Outside the Garden

You can prevent the yellowing of harvested broccoli by freezing it as soon as you remove it from the plant. Harvested broccoli heads can turn yellow quickly in a day or two and diminish in nutritional value if you do not consume them by then.

To preserve them and prevent yellowing, here is what you need to do:

  • Cut, wash and blanch the floret heads when they are green.
  • Place them in airtight bags and store them in the freezer.
  • Florets will stay green and fresh for up to ten days.

Conclusion

You have read how to care for your broccoli plants and prevent their yellowing. Let us review the important points that we learned from the article.

  • Broccoli can turn yellow due to maturity, pests and fungal infestations, among other reasons.
  • You can tackle yellowing due to maturity by harvesting the crop at the right time.
  • Reduce the spread of fungal disease by isolating the infected plant.
  • Companion planting helps to prevent pest infestation as well as fungal disease.
  • Give your broccoli plant a cool environment to grow in.
  • It is safe to eat yellowing broccoli, but it is best to avoid doing this as the taste is bitter and the nutrition is reduced.

Broccoli is a relatively easy plant to grow in your garden. After reading our expert tips and advice, you can now go a long way in harvesting a perfect batch of broccoli.

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