Cauliflower is a popular vegetable that belongs to the Brassicaceae group that notably contains cabbage, broccoli, Brussels sprouts, kale, and other related plants.
Brassicaceae, which contains mustard, is a commercially significant group.
Cauliflower cultivation is unquestionably tough due to the plant’s strict climate requirements.
Low temperatures during the vegetative stage, wet soil without standing water, and insect pest-free growth conditions are all key needs for cauliflower to provide the desired output.
Many farmers also experience difficulties with cauliflower production, such as cauliflower leaves turning yellow in certain situations. It can happen for a variety of causes.
In this post, we’ll go through all of the possible causes and their treatments.
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Cauliflower Production Requirements
Cauliflower is a chilly season plant that best thrives in nature, well-dug soil with a pH value around 6.5 or higher. A huge portion of organic material in the ground helps keep humidity.
To avoid ‘buttoning,’ the crop requires cold conditions, which means that numerous tiny heads grow rather than one huge one.
Cauliflowers are less cold-hardy compared to their cousins and should be sown after the final frost since the plant might be damaged in sub-freezing conditions.
This is typically cultivated in colder regions as fall produce and in the fall just crops matured will withstand cold.
It, therefore, generates a relatively humid and chilly environment. The optimal typical monthly temperature is between 15 and 20°C.
Warmer temperature & extended day duration is needed for the early types. Therefore, in the winter months or autumn-winter people like to grow it.
The crop placement largely affects the ultimate growth of the head of Cauliflower and thus the crops should be 46 cm away, allowing around 75 cm among rows.
Upkeep and care of Cauliflower have to create significant delicate heads consistently over the growing period.
The crops also need enough nitrogen, which must be supplied as a fertilizer side-dressing midway during the growing period.
Cauliflower heads may be discolored by sunshine, therefore when they grow 2.5 to 5.0 cm in diameter, the crop needs to be blanched, which is a technique that keeps its head white.
This is accomplished by collecting the tallest outermost leaflets at the top and binding them securely using twine.
Loosen the knot regularly to monitor the growth of its head, look for bugs, and let its head dry out following rainfall.
There are self-blanching forms that produce leaves that protect the head spontaneously. 90 to 120 days following sowing the cauliflower plant is prepared for harvesting
Cauliflower which is completely developed and appears white must be harvested and marketed as soon as possible.
If the gathering is postponed, the hue of the leaves will turn yellow, and their richness and beauty will be lost. As a result, it’s critical to harvest the Cauliflower when it’s fully mature.
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Why Are My Cauliflower Leaves Turning Yellow?
If a plant’s chlorophyll components are lost, the foliage becomes yellow. The leaves could also become yellow as a result of insect infestations, infectious diseases, or environmental stressors.
The cauliflower foliage can become yellow for quite a variety of factors The following contains a list of them.
- Natural Growth
- Underwatering
- Overwatering
- Nutrient Deficiencies
- Diseases and Pests
- Stress
Natural Growth
First, the most obvious cause of fading leaves is the plant’s normal development processes. Its developing energy is focused toward earlier, more prolific development as it grows.
After doing their function of bringing the plant to maturity, the elder leaves begin to fade away.
This fading is quite natural, and it will impact all crops of a similar type at the right period while at an equal pace.
If, on the other hand, the wilting affects the entire crop, with certain individuals suffering worse than another it’s typically an indication of stress.
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Underwatering
If your crop is stressed by not getting enough hydration, the colour of the foliage will fade.
Plants are failing to collect enough moisture from the ground and transmit it to the stems and leaves owing to a shortage of moisture in the soil.
As a consequence, the plants will have to use less moisture to perform photosynthesis. As a result, undesirable chlorophyll components that aren’t engaged in photosynthesis are discarded.
The leaves grow drier, crunchier, and yellow in hue. As a result, you must be cautious and consistent while feeding the cauliflowers.
Keep checking the ground (at least once per day), and if it appears to be dry, provide watering. Never overwhelm the crop plant roots with water; simply moisten the ground.
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Overwatering
Excessive moisture is a major issue in nearly every crop.
When the roots are submerged in water over an extended length of time, the tissues will decay owing to a shortage of appropriate ventilation.
When the roots begin to decay, they are unable to provide sufficient moisture to the crop and the greens begin to lose their chlorophyll pigment thus becoming yellow.
When you leave your ground damp all of the time, this is most likely the cause of your cauliflower foliage becoming yellow.
One can take the below steps to avoid an overwatering situation.
- When growing cauliflower, use a ground that drains well.
- Since cauliflower prefers somewhat damp soil yet not to have its roots soaked in water, employ little water regularly and for a short period.
- Incorporate as much natural material into the ground as possible, since it will aid in enhancing the soil’s physiological health and drainage.
- Mulches may be used to properly utilise water while cultivating cauliflower outdoors.
Nutrient Deficiencies
Low amounts of nitrogen, iron, magnesium and potassium, among other typical nutritional shortages in your ground, may turn plants yellow.
When plants acquire brown patches around their margins, and also yellowing or overall loss of hue, it’s a sure indicator that nutrition is a problem.
If you suspect your ground is deficient in essential elements, a simple testing kit helps validate your fears.
You may then use an appropriate fertilizer to correct the deficit and focus on natural soil development to avoid future issues.
Epsom salt (magnesium sulphate) can be added to the ground to increase the magnesium concentration and encourage the production of chlorophyll pigments.
Most such crop plants require potassium as nutrition. To avoid a potassium deficiency, you may purchase and use potassium fertiliser from the store. It will put an end to the problem.
Stress
Cauliflower is a cool-season crop sensitive to withering in extreme heat. The crop does quite well in daylight temperatures around 65 and 80 F. (18-26 degrees Celsius).
The plants usually wake up during the evenings or if the weather cools down. In the lack of rainfall, offer 1 to 12 inches (2.5 to 3.8 cm) of water each week and not allow the ground to dehydrate entirely.
Overwatering, on the other hand, might lead cauliflower to fade due to damp, waterlogged soil. On warm days, a coating of bark particles or any other mulch helps keep the earth cold and damp.
Diseases and Pests
Crops that are weakening due to pests and disease may typically begin to turn yellow. Look for apparent evidence of aphids, moths, or any other parasites, and also fungus or mildew stains.
Some of the pests and diseases are mentioned below –
Clubroot
Clubroot is a dangerous fungal infection that damages brassica plants like broccoli, cabbage, and cauliflower. Yellowing or weak leaves, as well as fading in summer weather, are the first signs of clubroot.
Early indications can be hard to identify if you see wilting cauliflower. The crop develops deformed, the club-shaped populace at the root system as the condition develops.
The infection, which resides in the ground and spreads swiftly towards other crops, must be eliminated as early as feasible
Verticillium wilt
Cauliflower is frequently affected by this fungal infection, particularly in humid, coastal regions. It usually affects crops in late summertime and early fall as they approach maturation.
Verticillium wilt typically occurs in the lower leaflets, causing them to wilt and become yellow. Starting afresh with healthier, disease-resistant crops is the safest alternative.
Because the fungus resides in the ground, transplants should be placed in a region of the yard that is rid of the infection.
Fusarium wilt
Lower leaflets are the first to become yellow accompanied by the whole plant. Leaves that have been impacted wilt, dry down, and then become fragile. It’s also possible that they’ll collapse from the branch.
To keep the infection under check, you must eliminate the diseased crops from the area. To limit disease transmission from one crop to the next, eliminate leafhoppers.
Maintain weed-free ground. Fungicides can also be used.
Conclusion
After going over all of the possible reasons why your cauliflower plants may turn yellowish we may say that the most important factors to consider are irrigation and disease pests infestation.
Water stress is a major cause of yellow leaves in several instances. Individuals frequently overwater or submerge their plants, causing them to show symptoms of infection.
As a result, it’s a good idea to keep a close eye on the plant’s moisture requirements and feed properly.
In addition, you must prevent disease bugs far from your valued crops.