Best Fertilizer For Cucumbers: A Comprehensive Guide On Types, Application Methods, Frequency, Benefits and more

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Quick Answer: Best Fertilizer For Cucumbers

Cucumber plants are heavy feeders and prefer soil amendments to meet their nutrient requirements. Low-nitrogen and phosphorus-based fertilizers can be used for cucumber plants. Different organic fertilizer options that can be usedare aged compost, worm castings, bone meal, blood meal, and fish emulsion. Fertilization can be started when the plants have established a few true leaves.

Are you interested in knowing the best fertilizers suitable for cucumber plants?

If yes, explore this comprehensive guide to help you choose the top fertilizers to enhance the growth of cucumber plants.

Let us get started!

Best Fertilizers Types For Cucumbers

Cucumbers (Cucumis sativus) are popular warm-season vegetables that grow well in garden plots or containers.

It is a heavy feeder and requires soil amendments in addition to watering for increased yields and healthy growth.

It has low nitrogen requirements. It needs phosphorus to trigger blooms and fruit sets and potassium to produce healthy plants.

In addition, it also requires secondary and micronutrients, including calcium, magnesium, and sulfur.

So, it may benefit from a regular fertilization regime using inorganic, organic, or a combination of both.

Next, let us go through different inorganic and organic fertilizers that may be suitable for your cucumber plants.

Best Inorganic Fertilizers For Cucumbers

Inorganic fertilizers are made from synthetic compounds and can be used to provide essential nutrients to cucumbers.

It is highly concentrated and makes the nutrients available to the plants in a readily available form.

Here are a few inorganic fertilizers that can be used for your cucumber plants:

1. Low Nitrogen Fertilizers For Cucumbers

Cucumber prefers low nitrogen fertilizers with NPK values 5-10-10 and 3-4-6. These fertilizers help the plants to produce more fruits. It is available in granular and liquid form.

How to Use/Apply?

  1. Apply the low-nitrogen fertilizer– Read the manufacturer’s instructions and apply the fertilizers evenly around the base of the plants without having direct contact with the stems. You may use a rake or hoe for incorporating the fertilizer.
  2. Side-dress the fertilizer– You may apply the fertilizer as a side dressing by making a furrow about 4-6 inches away from the plant’s stem.

You may watch this video for tips on growing NPK fertilizers:


Low-nitrogen fertilizers may promote the fruiting of cucumber plants rather than vegetative growth. It also helps in reducing the risk of diseases and pests.

Avoid overfertilizing as it may overburn the plants.

2. Phosphorus-Based Fertilizers For Cucumbers

Phosphorus-based fertilizers, including superphosphate or triple superphosphate, can be used to provide an adequate supply of phosphorus to cucumbers.

It is available in both granular and liquid forms.

How to Use/Apply?

  1. Apply phosphorus fertilizers- Determine the appropriate application rate of phosphorus-based fertilizer. Sprinkle the powder using a garden spreader or hand. It can also be used as a foliar spray.
  2. Use side-dressing- Apply fertilizers as a side-dressing.

Check out this video for tips on the benefits of growing super phosphate:


Phosphorus-based fertilizers are particularly used in their early growth stages especially if the soil is deficient in phosphorus.

It may acidify the soil and so, lime is used as an amendment to restore soil pH to normal levels.

Best Organic Fertilizers For Cucumbers

Organic fertilizers are made from organic ingredients that can be easily absorbed into cucumber plants.

It is biodegradable, sustainable, and safer for the environment. It can feed beneficial microbes to the soil.

Here are a few best organic fertilizers suitable for cucumbers.

1. Aged Compost For Cucumbers

Well-aged compost is popularly used as a soil amendment for providing nutrient reserves for cucumber plants. It can be used as mulch or worked before planting.

How to Use/Apply?

  1. Amend the soil with compost– You may add 3-4 inches of compost for new vegetable beds. Add one-quarter to one inch of compost for existing vegetable beds.
  2. Incorporate the compost– Once the compost is applied, gently work it to a top layer of soil using a rake. Water thoroughly to settle the soil.

Click this video for the best techniques for reusing old compost:

Pros And Cons

Well-aged compost helps in providing nutrients, including potassium, phosphorus, and micronutrients required by cucumbers.

It helps in promoting aeration and improving drainage. Also, it helps in increasing disease resistance and cuts the competition from weeds.

2. Bone Meal For Cucumbers

Bone meal is a type of organic fertilizer derived from ground-up animal bones. It has a high content of phosphorus, potassium, and calcium which help to boost cucumber growth.

How to Use/Apply?

  1. Prepare bone meal– You may purchase bone meal fertilizers or prepare by grinding chicken or animal bones in a grinder thoroughly.
  2. Apply bone meal– Add 4-5 teaspoons of bone meal and sprinkle around the base of cucumber plants.

Here is a useful video on using bone meal as an organic fertilizer:

Pros And Cons

Bone meal acts as a slow-release fertilizer releasing nutrients over several months and help in promoting cucumber plants. It also improves the structure and quality of the soil.

Take care as it may attract animals to the garden.

3. Worm Castings For Cucumbers

Worm castings are an organic slow-release fertilizer rich in beneficial organisms and nutrients. It promotes healthy growth and high yields of cucumbers.

How to Use/Apply?

  1. Prepare the planting area-Remove the weeds or debris and loosen the soil
  2. Apply worm castings– Take a quarter to half a cup of worm castings. Sprinkle them around the base of the cucumber plants. Water the plants and soil thoroughly. Repeat the application as recommended.

Check out this useful video for details on applying worm castings:

Pros And Cons

Worm-castings are a potent source of essential nutrients for your growing cucumber plants. It will help improve soil structure and enhance microbial activity.

It creates an environment less favorable for harmful pathogens.

4. Blood Meal For Cucumbers

Blood meal is an organic soil amendment that adds higher levels of macronutrients to the cucumber plants. It is a dry powder of animal blood obtained from slaughterhouses.

How to Use/Apply?

  1. Apply blood meal– Perform a soil test and check if the soil is deficient in nitrogen. Purchase a blood meal and sprinkle the fertilizer as recommended around the base of the plants. Alternatively, you may dilute the blood meal with water and pour it on the soil.

Click this video for additional information on using organic blood meal:

Pros And Cons

Blood meal provides essential nutrients for cucumber plants if suffering from nitrogen deficiency.

It gives beneficial microbes for maintaining soil structure. Sometimes, it provides excessive nitrogen that may burn the plants.

5. Fish Emulsion For Cucumbers

Fish emulsion is another organic soil amendment that can be used to provide nutrients to cucumber plants and speed up their growth.

It is made from fish oil and other fish remains. It can be added as a soil drench, foliar spray or mixed with the compost pile.

How to Use/Apply?

  1. Dilute fish emulsion– Add three tablespoons of fish emulsion to a gallon of water.
  2. Add diluted emulsion– Pour the diluted fish emulsion into your plant’s soil. It can also be applied as a foliar spray. Apply once every two weeks as required.

Check out this video for tips on using fish emulsion in a vegetable garden:

Pros And Cons

Fish emulsion is high in nutrient value and helps to boost your cucumber plants. It also reduces the susceptibility of plants to diseases by boosting soil structure.

But, it may have a strong smell.

When And How Often Do I Fertilize Cucumbers?

Cucumbers require a regular fertilization regime starting from planting till the fruiting stage.

The frequency of fertilization depends on the type of fertilizers used. You may check the manufacturer’s instructions for more information.

Planting time

Cucumber plants may benefit from two inches of aged manure or compost before planting and work to a depth of about 6-8 inches.

You may side-dress your plants with compost or well-rotted manure.

Fertilize every 2-3 weeks during the growing season. It also needs fertilizing the crop when you are mulching around the plants. It will give the plant a boost and keep weeds at bay.

Flowering Stage

You may also fertilize the plants with 5-10-10 fertilizers about one week after the plants start blooming.

It is preferable to use liquid fertilizers at this stage. Reapply every three weeks thereafter directly to the soil around the plants.

Watch for signs of over-fertilization including yellowing of cucumber leaves. In such instances, stop fertilizing and flush the excess fertilizers from the soil.

Liquid Vs Granular For Cucumbers: Which is Better?

Both liquid and granular fertilizers can be used for cucumber plants for bountiful yields throughout the summer. It depends on the stage of cucumber growth and personal preferences.

Granular fertilizers are slow-releasing and provide a steady amount of nutrients to your cucumber plants. These fertilizers resemble tiny pellets or small granules.

 It is preferable to use them when you plant the cucumbers and while adding mulch. Avoid sprinkling directly on the plant as it may burn and damage the crop.

Liquid fertilizers are available in a concentrated form that can be mixed with water or ready-to-use foliar liquid.

It can be applied directly to the soil around the plants and can also be used as a foliar spray.

 It is used when the plants start growing and bearing fruits. It requires frequent feedings as it can wash out of the soil quickly.

Check out this video for comparing granular and liquid fertilizers:


Can you use high-nitrogen fertilizers for cucumbers?

It is preferable to use low-nitrogen fertilizers for cucumbers. The fertilizers high in nitrogen may encourage vegetative growth and spark growth spurts. So, the plants will focus their energy on growing vines, leaves, and shoots. Also, it will cause cucumber flowers to not open and will result in no fruit.

How to use Epsom salt in the cucumber vines?

Epsom salt can be added to the cucumber vines to provide a dose of magnesium. Dissolve about 1-2 teaspoons of Epsom salt in a gallon of water. Add diluted solution around the base of the plants. Reapply once in 4-5 weeks for better yields.

What is a homemade fertilizer for cucumber vines?

A recipe for homemade fertilizer for cucumber vines involves the use of sugar and dry yeast. Add one tablespoon of sugar and dry yeast in 10 quarts of water. Mix it thoroughly and leave it for atleast 2 hours. Remix it and add a pint of fertilizer per plant.

Can you use cow manure for cucumber?

Cow manures can be used for boosting cucumber yield. It helps in providing organic matter and improves soil structure. It is preferable to use manure once a week or twice a week during the growing season. However, take care to use only aged manure to avoid burning of plants.

Bottom line

I hope this guide has provided you with actionable information to make well-informed decisions in selecting the best fertilizers for your cucumber plants.

You may write to me for any suggestions and feedback.

Do share the guide with your friends and family to help them out too!

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