Yellow Cucumbers — Why Are My Cucumbers Yellow?

Last Updated on October 29, 2021 by Grow with Bovees

Do you find yourself in a pickle or as cool as a cucumber?

Though it’s not a laughing matter, when you find yourself “in a pickle” it means you are faced with a problem with no easy answer.

If you are reading this your plants most likely have issues or perhaps you didn’t plan on a home garden full of yellow cucumbers.

Healthy Cucumber Plants and Crop Rotation

Cucumbers (Cucumis sativus) are 90% water, the fourth most popular grown vegetable in the world, (onions being in 2nd place and peppers and chilies in 7th), and although cucumber plants produce fruit, it doesn’t form part of the fruit family as many seem to claim.

Cucumber plants have a shallow root system. They grow best in warm weather, so you can start your growing season from mid-April, implementing floating row covers to grow healthy cucumbers. 

Some varieties have long vines which may need a trellis (garden obelisk), but for a small garden area, rather plant the bush-types instead.

Disease and fungal infections can stay in garden soil for up to 8 years, and it’s therefore important to follow strict crop rotation principles which will also help with nutrient balance in the soil, while raised garden beds create a physical boundary and prevent cross-contaminating healthy plants.

Now that we know what it requires to grow a healthy plant, let’s dive into the details and discuss the reasons why cucumbers turn yellow, nutrient deficiencies, and what can be done to fix It.

Why Are My Cucumbers Turning Yellow?

Cucumbers turning yellow could have any one of a number of potential causes. Most commonly, overwatering, and nutrient deficiency lie at the root of it all.

Although it may be easy to fix in some cases by just adding lots of compost or organic mulch, there are times when you find your garden beds covered with potato leaf hoppers, aphids, or spider mites and when things get really bad, we look for answers.

In my opinion, the long-term success of fruit production lies in soil preparation and following a strict garden plan.

Here is a breakdown of the top 8 reasons why you have yellow cucumbers:

1. Cucumber Varieties

The type of fruit you’ll harvest depends very much on what type of cultivar you’ve planted. So unless you’ve planted a yellow cucumber seed, you shouldn’t be producing any yellow cucumbers.

That said, other varieties to consider include dwarf-vine or bush types, mini or snacking cucumbers, but whichever you decide to plant, select resistant varieties when possible.

2. Inconsistent Water

Improper soil moisture plays a vital role in fungal diseases. If you plant in outside ground gardens, remember to include rainfall in your total moisture tally because your plants require only about 1 – 2 inches of water per week.

Where drip irrigation is not available, plants should be watered deeply on a weekly basis, providing at least an inch of water because if you produce bitter cucumbers it may be due to insufficient watering.

Lack of Water vs Overwatering

Motivate water retention in the soil by adding a healthy layer of mulch in your veggie garden, using straw, or any other organic material.

Overwatering removes essential minerals, it will be the likely source of leaf discoloration and cucumbers turning yellow.

There will be a time during the rainy periods you’ll only need to water a couple of times per week, or as needed, while nature takes its course.

Cover the soil with organic matter, keep moisture off leaves, avoid watering overhead, and don’t splash leaves with water, especially during long periods of wet, humid weather. 

3. Sunlight and Temperature Fluctuations

Cucumbers grow best in direct sunlight. Not enough sunlight will cause an insufficient supply of chlorophyll (the green pigment found in plants) and cause chlorosis, revealing the yellow pigment beneath, which, in conclusion, means your plant is turning yellow due to lack of sunlight.

Nitrogen is essential and responsible for converting sunlight to usable plant energy and therefore, a lack of nitrogen reduces the plant’s ability to trap energy through photosynthesis and generate healthy green coloring in growing plants. 

See also  Cucumber Leaves Turning Yellow

4. Lack of Pollination Causes

Cucumbers are self-pollinating, which means that a single plant produces both male and female flowers. However, conditions have to be just right for pollination to take place.

Because the flowers are sensitive, they can be damaged by conditions such as drought, heavy rain, or extreme heat. Given the short lifecycles of cucumber flowers, the pollinators may not be able to get to the plants in time.

Pollination From Insects in Your Garden Vegetables

Pollination from bees is essential, but a flower must be pollinated within 4 hours of opening to be successful, while pollination from insects is just as vital to protect your pollinators by using natural insecticide where possible.

That’s a lot of pressure on the bee population, it’s good to know that while some insects can be harmful there are beneficial pollinators, such as butterflies and hummingbirds.

Ultimately, the goal is that once a flower is pollinated it will start to wilt 7 days after pollination, the flower dries up and the cucumber begins to form, whereas poor pollination will produce flowers but no fruit.

Lack of pollination could be the cause of deformed vegetables. It impacts the yield, size, and weight of your garden plants. Incomplete pollination could be a result of using pesticides that kill the pollinators in your garden.

Female Flower and Pollination

The first blossoms often drop from the vines, since the first flowers to appear on the vines are male.

The female flowers, which open later, have a swelling at the base that forms the fruit, also known as the ovary and after pollinating the female flowers the fruit develops.

Whenever there’s a lack of insect pollinators consider choosing a cucumber variety that won’t require pollinating.

Many newer varieties produce mostly female flowers while other varieties require pollinating with male flowers, in which case some of the seeds in the packet will be pollinator plants that produce the male flowers.

Some varieties are parthenocarpic which means there’s no need for the male plants to produce fruit so be on the lookout for these types as they do not require the presence of insect pollinators. 

5. Lack of Nutrients and Fertilizer in Yellowing Cucumbers

Here are a few things to consider when cucumber leaves are turning yellow or showing signs of yellow spots during the growing season.

The balance of nitrogen is plentiful in the air and combines chemically with other elements to form extra nitrogen compounds.

The most common nutrient problem associated with chlorosis is lack of iron, but manganese or zinc can not be ruled out without further investigation into the issues regarding the plant’s growth.

The correct diagnosis will ensure that the correct precautionary measures are taken.

Lack of Nutrients and Fertilizer

Nutrient deficiencies in growing cucumbers show up in both the leaves of affected plants and fruit, which may turn yellow due to the lack of balanced fertilizer and all the nutrients required to grow healthy crops.

Yellowing is an indication of nitrogen deficiency in most cases, and to fix this, apply a balanced mix of nutrients into the fertilizer to the root zone area at planting time.

Levels of Nitrogen

Too much nitrogen may cause overgrowth in foliage and produce hardly any fruit, hence the important role of a mix of nitrogen in large amounts that is generally considered enough to encourage plant growth.

Nitrogen fixation is defined as any process that produces a level of nitrogen.

That said, nitrogen is the first component to become depleted. For a slow, but consistent release of nitrogen, add compost regularly. Compost is an excellent source of slow-release nitrogen for your cucumber plants.

Fertilizers for Yellowing Cucumber Skins

As a highly mobile element, potassium deficiency will quickly turn your normal cucumbers from a deep green color to yellow and may cause stunted growth because the essential nutrients are not available to plant roots.

The mobility of potassium in plants plays a key role when there is a lack of nutrients and can lead to diseases in the appearance of cucumber leaves on affected plants. 

See also  Black On Pepper Plants — Why Are My Peppers Turning Black?

When cucumbers grow they specifically crave potassium and when your cucumber plant is “hungry” they need more phosphorus and potassium to produce cucumbers successfully.

Potassium Deficiency in Plants

Like most plants, a cucumber plant requires all the essential elements to complete its cycle. Phosphorus and potassium deficiency are common in gardens with insufficient nutrients, which may turn green cucumbers yellow.

Phosphorous is essential for the normal development of the roots, flowers, fruit, and seeds, and it promotes strong plant growth and development of a healthy root system.

Potassium deficiency appears first in the older leaves and fruit presents abnormal growth with brown spots.

6. Plant Diseases: Cucumber Mosaic Virus (CMV) and Aphids

The disease may affect the growth and the appearance on cucumber leaves and infected cucumber fruits often remain small, malformed, and discolored.

The cucumber mosaic virus is a viral disease transmitted by aphids and while it attacks a variety of plants, there is no known cure. Infected plants should be removed and destroyed.

The virus can be controlled by applying reflective mulches that can aid in aphid control, although it can also be treated with mineral oils such as neem oil or insecticidal soap applications in a severe infestation.

7. Bacterial Disease and Bacterial Wilt Often Caused by the Cucumber Beetle

The striped cucumber beetle has long black stripes down its back, and the spotted cucumber beetle is slightly bigger and has black spots.

Both these adult beetles will feed on the leaves, fruit, stems, and flowers and the first symptoms of pest attack are wilting of individual leaves followed by wilting of individual stems before premature death of the entire plant.

Symptoms of bacterial wilt scar the fruit caused by the cucumber beetles feeding damage and once the plant is infected it cannot be saved.

To discourage cucumber beetles from spreading the bacteria, remove dead leaves, plant in wide row spacing, and keep your garden clean of infected cukes, leaf litter, and debris.

8. Fungal Disease 

As a preventative treatment, fungicide is an excellent solution that can help to protect new or uninfected plants.

It is more likely to infect densely planted vines. Proper spacing is vital for good air circulation and staying clear of planting vines in wet, poorly drained areas.

Signs of Fungal Growth

The first signs of plant downy mildew include pale yellow leaf spots, which can affect both the upper and underside of leaves, reduce yield, premature death, and affect fruit quality.

The first lesions appear angular, whereas powdery mildew has a noticeable yellow or white mottling.

In powdery mildew, these white powdery spots can quickly expand into large blotches and cover the entire plant, including leaves, stems, and fruits.  The infected leaves become yellow, malformed, and may drop prematurely.

In severe cases, powdery mildew can spread rapidly especially during windy days when the wind can spread spores, and once symptoms are noticed it’s most likely too late to apply a fungicide.

Don’t overcrowd plants and avoid overhead watering, rather water the plants from the base and apply appropriate fungicide to control heavy outbreaks.

Fusarium Wilt Also Known As Cucumber Wilt

Fusarium wilt spores favor moist warm soil and symptoms include rotting of seedling stems and brown lesions.  

Verticillium Wilt 

Typically develops symptoms during fruit set, yellow cucumber leaves will collapse and include discoloration of vascular tissue in roots.

Because fungus can survive in the soil for many years, plant disease-resistant varieties, especially fungicide-treated seeds and follow a healthy crop rotation routine. 

Cucumber Harvest: When Is the Best Time

Cucumbers fresh from the garden are a summer treat and the new mini varieties are a great healthy alternative when you’re making lunch boxes or looking for an on-the-go snack!

Ultimately the goal is to avoid overripe cucumbers by harvesting them every few days while dark green and when they’ve reached their optimal flavor and tenderness.

In doing so the plant produces new fruit throughout your growing season and you’ll have a steady supply of ripe cucumbers.

See also  Cucumber Leaves Turning Yellow

As a quick-growing crop, it’s no surprise that due to the rapid fruit growth cucumber plants must be harvested before over-ripening, blossom end rot or when fruits begin to yellow.

Why Cucumbers Are Turning Yellow

Fruit that are allowed to stay on the vine too long divert the plant’s energy away from producing new fruit, and they will become soft, and the seeds will be large and begin to harden.

Very ripe cucumbers turn deep yellow and the flesh will be spongy but while they are edible, many people don’t enjoy mushy pickles.

Overripe cucumbers can be picked after their prime and used for pickling.

Are Round Yellow Cucumbers Normal?

If you enjoy burpless cucumber varieties and you’re up for a fun sweet yellow cucumber I recommend the lemon cucumber. They are not bitter, thin-skinned, and delicious to eat fresh from the garden.

This yellow cucumber variety fruit is the size, shape, and color of a large lemon with a nearly round to somewhat oval shape.

The inside flesh has the appearance of a lemon wedge with flesh that colors from a pale green to pale yellow to an orange color at maturity.

How Can You Tell if a Cucumber Is Bad

Ripe slicing cucumbers are usually long, smooth and green while pickling cucumbers are usually smaller and have bumpy skin.

When picking cucumbers remove all over mature, large, and poorly shaped fruit from the vines to keep plants producing.

Why Are My Cucumbers Orange and Yellow?

The most common mistake made by many growers is harvesting too late. This will motivate over-ripening and the cucumber gets a yellow color.

They are divided into two broad groups, pickling, and slicing, on the basis of shape and color and the best preventative measure you can take is to buy any disease-resistant cucumber variety.

Pickling types are short and blocky and have white or black spines on the cucumber, fruit is generally dark green at the stem end and almost white at the blossom end.

Fruit with white spines turns light yellow or white when overmature while black-spined types turn orange.

What Does an Overwatered Cucumber Plant Look Like?

Soil saturated with water will cause a plant to wilt due to the lack of oxygen in the soil and you should always remove yellow leaves to limit plant diseases.

Avoid over-watering especially during the rainy season because stressing the plants may be the reason you have misformed bitter-tasting cucumbers with pointed ends.

What Can I Do With Yellow Cucumbers?

Eating discolored deformed cucumbers likely won’t hurt you, but you probably don’t want to try it because they become bitter and unappetizing while some varieties naturally produce pale yellow cucumbers that are perfectly fine to consume.

When your stunted cucumbers turn yellow and fall off, they haven’t ripened appropriately and lack the proper growing conditions.  

Unless you are trying the rid of puffy eyes or treat burnt skin you have one of two choices: one is to add the most damaged to your compost pile and the other for pickling or preserving cucumbers. 

Preserving Yellow Cucumbers: Pickling and Relish – Can You Eat Yellow Cucumbers?

Relish is a good use of yellow cucumbers because the bitter taste combined with the pickling ingredients in the boiling water canner method ends up as a delicious condiment we enjoy and share. 

We love the Chinese yellow and Dosakai cucumbers for their fresh twist, they’re mild, bright yellow, delicious, and great for slicing or pickles. 

As the skin is sweet they can be used raw in salads (rinse well with cold water), or cooked in soup and stir-fry recipes.

Affected Plants and Cucumbers Turning Yellow

Cucumbers are so much more than pickles and their great taste star in a wide variety of our meals in everyday life.

Pin this post for quick access whenever you find yourself faced with a yellowing cucumber.

After reading this article, the only pickle you should have in your life should be the one on your sandwich and that’s what I call a happy ending!

Resources;

https://www.worldatlas.com/articles/the-most-popular-vegetables-in-the-world.html

https://www.scientificamerican.com/article/the-problem-with-honey-bees/