I love potatoes, and I have grown potatoes over the years. Based on this experience, I will be sharing some recommended fertilizers for potatoes, when and how to apply these fertilizers for best results, as well as the nutrient requirements for potatoes to achieve healthy growth. My choice of fertilizers is based on the formulation of the fertilizers and not the brand primarily.
Potatoes are a heavy feeder crop; the yield from a potato garden is directly proportional to the level of fertilizer the potato plants receive from the soil and through supplementation. Relying solely on the nutrients in the soil will not give you the desired yield; you still need to supplement with commercial fertilizers to achieve the best yield. I have tried both options in the past, and I can tell the difference, hence my recommendation.
Potatoes need a fertilization program to achieve high yields and quality tubers. This program must consist application of fertilizers from germination to maturity. Potato needs fertilizers that can supply the primary nutrients, nitrogen, phosphorus, and potassium, alongside micronutrients like calcium, magnesium, zinc, boron, iron, manganese, and sulfur. These nutrients support lush foliage growth, root development, flowering, tuber formation, and overall plant vigor.
Inadequate fertilization can lead to stunted growth, reduced yields, and poor tuber quality, while excessive fertilization can result in environmental issues and wasted resources. Hence, choosing the right fertilizer and applying the right quantity can make the desired potato yield achievable. That said, here are some top fertilizers for potatoes; these fertilizers contain the essential nutrients in the right ratio to support the growth and development of potatoes.
- Old Cobblers Farm’s Seed Potato Fertilizer
- Down To Earth Root Zone 1lb Soluble Formula
- Burpee Organic Plant Food & Potting Soil Combo, 4 lb
- RAW Potassium
- Greenway Azomite Rock Dust Fertilizer.
1. Old Cobblers Farm’s Seed Potato Fertilizer
The Old Cobblers Farm’s Seed Potato Fertilizer is a plant food specifically formulated for potato plants; the fertilizer contains a blend of nutrients with an NPK ratio of 8-16-16 to promote root development and robust growth. Old Cobblers Farm’s Seed Potato Fertilizer is slow-release, making it ideal for long-term potato feeding. Also, this fertilizer is safe and can be used without any fear of leaching into the underground water and burning of the plant parts.
Characteristics:
1. Specialized 8-16-16 NPK formulation
2. Balanced mix of essential nutrients, with an emphasis on phosphorus and potassium
3. Slow-release technology for efficient nutrient delivery
4. Improves soil quality and contributes positively to the ecosystem
5. Compatible with diverse soil types and potato varieties
6. Natural, effective, and efficient for potato cultivation
Formulation Details:
– Date First Available: January 15, 2024
– Manufacturer: Old Cobblers Farm
– Tailored for potatoes to meet specific nutritional needs
– Ingredients promote soil health and nutrient-rich environment
– Efficient nutrient release with gradual delivery
– Enhances yield and quality of potato crops
– User-friendly application for various soil types and potato varieties
– Country of Origin: USA
Application Guide
Target Plants: The Old Cobblers Farm’s Seed Potato Fertilizer is typically formulated for potatoes and other garden crops.
Application Forms: Available in granules.
Application Rate: Apply 5 lbs of Old Cobblers Farm’s Seed Potato Fertilizer per 500 sqft.
How To Apply: Mix the Old Cobblers Farm’s Seed Potato Fertilizer into the soil following the application rate, plant the potato, and water the plant thoroughly.
When To apply: Apply the potato seed fertilizer during planting, mid-season when the potato is flowering and tuberizing, and lastly anytime the potato plant shows any sign of nutrient deficiency.
2. Down To Earth Root Zone 1lb Soluble Formula
The Down To Earth Soluble Root Zone Formula is a powerful blend of beneficial microbes, mycorrhizae, and organic nutrients designed to improve soil health and promote strong root development in potato plants. This fertilizer is made from organic materials that are safe for the environment and can be used on potatoes and other garden plants.
Characteristics:
– Natural and organic fertilizers
– Soil amendments, composts, and potting media
– Works with microorganisms and organic matter in the soil
– Blended from best sources of organic nutrients
– No synthetics or low-quality fillers like poultry waste
– Derived from plant, animal, or mineral resources
– Strengthens soil health
– Three forms: dry, water-soluble powder, and liquid
– Professional grade and ultra-concentrated formula
- Diverse mix of bacterial species
– Promotes enhanced activity in the rhizosphere
– Improves soil structure and root growth
– Ideal for inoculating all types of plants
– Establishes biological diversity in garden soils, potting mixes, and soilless media
– Shelf stable with a two-year expiration date
– Should be stored dry at room temperature for maximum viability
Additional Information:
– Can be watered into porous media in gardens, seed beds, or propagation trays
– Can be applied directly to seeds, roots, and cuttings when transplanting
Application Guide
Target Plants: The Down To Earth Soluble Root Zone Formula is typically formulated for potatoes, tomatoes, and other garden crops.
Application Forms: Available in powder form.
Application Rate: Apply 1 tablespoon of The Down To Earth Soluble Root Zone Formula per gallon of water.
How to Apply: Dilute the Down To Earth Soluble Root Zone Formula in water in a proportionate quantity of water and apply to potatoes directly at the root zones using the irrigation drip lines.
When to Apply: Apply the Down To Earth Soluble Root Zone Formula throughout the growing season and anytime to correct potassium deficiency symptoms.
3. Burpee Organic Plant Food & Potting Soil Combo, 4 lb
Burpee Organic Plant Food and potting soil combo is an ideal planting medium and fertilizer for potatoes, tomatoes, and other garden crops. This fertilizer contains a blend of essential nutrients necessary for the healthy and bountiful growth of potatoes. The Burpee Organic Plant Food is made from organic materials, making it safe for regular use without fear of leaching and burning of plant parts.
Characteristics:
– Organic plant care bundle
– Includes a 4lb bag of Burpee Organic Tomato & Vegetable Granular Plant Food and a 9-quart bag of Burpee Premium Organic Potting Natural Soil Mix
– Granular plant food provides essential nutrients, calcium, and minerals for up to 3 months
– Potting mix contains plant food and moisture-retaining coconut coir
– Ideal for vegetables, herbs, flowers, trees, shrubs, and patio containers
– Provides continuous nourishment for vibrant container gardens and raised beds
– Easy to apply granules for instant and long-term growth
– Potting mix retains water and slowly releases nutrients for up to 3 months
Formulation Details:
– Granular plant food provides major and minor nutrients for plants and soil health
– Potting mix contains sustainable coconut coir for moisture retention
– Both products provide nutrients for up to 3 months
Additional Information:
– Use for planting flowers, vegetables, or herbs in pots
– Burpee guarantees healthy, high-quality products
- Committed to the satisfaction and success of all gardeners
Application Guide
Target Plants: The Burpee Organic Plant Food is typically formulated for potatoes, tomatoes, cucumbers, and other garden crops.
Application Forms: The fertilizer is available in granule form.
How to Apply: Apply the fertilizer at the root zone of the potato plant and cover the with topsoil, then water thoroughly to activate the fertilizer. If you are planting the potato in pots, you can use the potting soil for the best results.
When to Apply: Apply the fertilizer at the beginning of planting, at flowering, and during tuber formation. You can also apply anytime when the potato plants start showing deficiency symptoms.
4. RAW Potassium
The RAW Potassium is a fertilizer formulated to promote vigorous growth and stress resistance in potato plants. RAW Potassium contains high potassium, which is essentially useful for large tuber development and correcting potassium deficiency. This fertilizer is water-soluble and can be applied through irrigation to direct root zones and foliar application through the plant leaves.
Characteristics:
– Technical grade plant supplement
– Contains 50% soluble potash
- Completely water soluble
– Used for treating deficiencies or boosting potassium levels
– Increases sugar content in plants
– Promotes healthy plants, corrects deficiencies, and increases fruit quality
- Easy to use and apply
Formulation Details:
– Analysis: 0-0-50
- Soluble Potash (K2O): 50%
– Derived from Potassium Sulfate
Additional Information:
– Available in 2 oz., 8 oz., and 2 lb. packages
– Recommended dosage: 1/16 to 1/8 tsp per gallon in reservoir
– Increases sugar content in sap, leading to healthier plants
- Feeding with NPK RAW Solubles is easy and effective
– Toxic levels of potassium are possible with overfeeding, so measure carefully
– Can make up to 40,000 gallons of solution
– Designed to be used in conjunction with RAW Soluble Micro-nutrient Line
– Positive customer reviews, with some concerns about value for money
Application Guide
Target Plants: RAW Potassium is typically formulated for potatoes, tomatoes, and other garden crops.
Application Forms: RAW Potassium is available in powder form.
Application Rate: Add 1/8 tablespoon per 2 gallons of water.
How to Apply: Dilute the RAW Potassium in gallons of water and apply to the potatoes through irrigation water.
When To apply: Apply RAW Potassium during flowering and tuber formation to aid bigger and larger tubers. This fertilizer can also be applied to correct deficiency symptoms of potassium in potatoes.
5. Greenway Azomite Rock Dust Fertilizer.
Greenway Biotech Azomite Rock Dust Fertilizer is a natural plant food that contains essential nutrients and minerals to support the healthy growth of potatoes and other garden crops. Aside from benefiting the plants through the provision of essential nutrients, Azomite Rock Dust Organic Fertilizer also improves the soil conditions, making it ideal and comfortable for the growth of plants; Azomite Rock Dust Organic Fertilizer helps lower soil pH, repel pests that may reduce the quality of the crop, and generally increase crop yield, Interesting, Azomite Rock Dust Organic Fertilizer is a slow-release fertilizer that can feed the potato plants for a very long time.
Characteristics:
– Azomite Powder (Micronized) 0-0-0.2
– Contains approximately 70 trace mineral elements and micro-minerals
– Mined from mineral-rich volcanic ash deposits
– Approved by the Organic Materials Review Institute (OMRI)
- Used to improve the mineral content of nutrient-depleted soils
– Enhances root systems and plant vigor
– Increases crop yield
– Improves plant immunity and pest resistance
Formulation Details:
– Contains Soluble Potash 0.2%, Calcium 1.8%, Magnesium 0.5%, Chlorine 0.1%, Sodium 0.1%
– 100% naturally derived
– Safe for plants
– Ideal for amendments as a trace mineral resource
Application Guide
Target Plants: The Azomite Rock Dust Organic Fertilizer is specially formulated for potatoes, tomatoes, cucumbers, and other garden crops.
Application Forms: The Azomite Rock Dust Organic Fertilizer is available in powder form.
Application Rate: Apply 1 pound of Azomite Rock Dust Organic Fertilizer per 10 sq ft.
How to Apply: Apply Azomite Rock Dust Organic Fertilizer before planting, during land preparation by incorporating directly into the soil. For bed application, just sprinkle the fertilizer around each plant. Water thoroughly after application.
When to Apply: Apply during land preparation and when the potato starts producing flowers and tubers.
Organic Fertilizers for Potatoes
Potatoes can also thrive on organic fertilizers. Compost, manure from animal origin, vermicompost, and, fish emulsion are top organic fertilizers that top organic fertilizers for potatoes. Obviously made from natural materials, organic fertilizers are safe and cheap for use; you do not need to worry about any implications when applying organic fertilizer to potatoes.
Aside from being a source of nutrients for potatoes, organic fertilizers also help improve the soil structure and provide an ideal environment for soil microorganisms to thrive and carry out several biological activities that can contribute to the sustainability of the environment. Globally, the use of organic fertilizers for crop production is being encouraged as organic fertilizers contribute to safe food production and a safe environment for plants and animals.
Organic fertilizers like manure are best applied during land preparation. They are incorporated into the soil before planting. Compost and vermicompost can be applied as top or side dressing as the potato plants emerge. Fish emulsion is best applied through irrigation water directly to the root zone of the potato plants.
When and How to Apply Fertilizers To Potatoes
The time and how you apply fertilizer to potatoes play a crucial role in ensuring optimal growth and yield. Here are some guidelines to follow:
At Planting Time: Apply fertilizer to potatoes before planting by incorporating a balanced organic fertilizer or organic fertilizers like manure into the soil before planting. This initial application provides the new potato plant necessary nutrients for early root development and shoot growth. The best recommendation is to apply a fertilizer with a balanced N-P-K ratio, like Old Cobblers Farm’s Seed Potato Fertilizer or Greenway Azomite Rock Dust Fertilizer.
During Vegetative Growth: The Vegetative growth nutrient is Nitrogen, so as the potato plants grow and develop foliage, they require additional nitrogen for robust growth. Apply a nitrogen-rich fertilizer, such as Down To Earth Root Zone 1lb Soluble Formula or Burpee Organic Plant Food & Potting Soil Combo, around 4-6 weeks after planting. Apply this fertilizer by side-dressing the fertilizer along the rows. Do not apply the fertilizer directly to the roots, and avoid direct contact with the potato’s vine to avoid burning or scorching of the plant parts.
Tuber Bulking Stage/Tuberization Stage: During the tuber formation stage, when the potato plants begin to form and enlarge their tubers, they require a boost of phosphorus and potassium; these two nutrients aid tuber development, flowering, and strengthens the potatoes against physical and biological damage, that is, pest and diseases. Apply a balanced fertilizer with a higher phosphorus and potassium content, such as Old Cobblers Farm’s Seed Potato Fertilizer or RAW potassium fertilizer, around 8-10 weeks after planting through the side-dressing method.
Foliar Feeding: Aside from direct application of fertilizer to the soil, you can apply fertilizers to potato leaves, and the plant will still utilize the fertilizers better; this is called foliar feeding. You need a soluble fertilizer formulated for foliar application and spray it directly onto the leaves using a garden bottle sprayer or knapsack sprayer.
Watering After Fertilization
Watering the soil after applying fertilizer is highly recommended. This is because most of the fertilizers are in solid granular form, so they need water to dissolve and release the nutrients for the potato to use. Also, watering helps to move the nutrients in the fertilizer from one zone to another within the soil, particularly to the root zones where the potato roots can take up the nutrients.
Soil Preparation for Potato Cultivation
Potatoes thrive in well-drained, loose, and nutrient-rich soil with a slightly acidic pH between 5.0 and 6.5. Proper soil preparation is crucial for a bountiful potato harvest. Before planting potatoes or any crop, I usually recommend testing the soil’s pH level and adjusting it if necessary by adding lime to raise the pH or sulfur to lower it.
Potatoes grow best in soil high in organic matter for optimal growth. Organic matter is derived from organic fertilizers. So it is advisable to incorporate well-rotted compost, aged manure, or other organic materials into the soil before planting. This not only enriches the soil with essential nutrients but also improves its structure, drainage, and water-holding capacity.
After incorporation of the fertilizer, loosen the soil to a depth of at least 8 inches using a garden fork or tiller. This allows the potato tubers to develop properly and encourages good air circulation and water drainage. Avoid compacting the soil, as potatoes prefer a light, fluffy texture. If your soil is heavy or clay-like, consider adding amendments such as sand, perlite, or vermiculite to improve drainage and aeration. Conversely, if you have sandy soil, add compost or peat moss to increase water retention and nutrient availability.
You can create raised beds or ridges for planting potatoes. This helps improve drainage, warms the soil faster in the spring, and makes harvesting easier. Ensure the beds or ridges are at least 8 inches high and 12 inches wide, with adequate spacing between rows for cultivation and maintenance. Proper land preparation creates an ideal environment for potatoes to thrive, leading to a bountiful and healthy harvest.
Fertilizer Application Safety
When working with fertilizers for potato plants, it’s essential to follow these safety precautions and best practices for both personal safety and environmental protection:
- Read and follow all label instructions carefully, including recommended application rates, timing, and any specific warnings or precautions.
- Wear appropriate personal protective equipment (PPE), such as gloves, goggles, and a respirator or dust mask, to avoid skin, eye, and respiratory exposure.
- Avoid applying fertilizers on windy days to prevent drift and minimize the risk of inhalation or unintended exposure.
- Keep fertilizers away from water sources, such as streams, ponds, or wells, to prevent contamination and protect aquatic life.
- Store fertilizers securely in their original containers, away from children and pets, and in a cool, dry place.
- Dispose of any unused fertilizers or empty containers properly, following local regulations and guidelines.
- Wash hands thoroughly after handling fertilizers, and change clothing if it becomes contaminated.
- Consider using organic or slow-release fertilizers, which can be safer for the environment and reduce the risk of over-application or leaching.
Conclusion and Recommendation
Proper balanced fertilization is crucial for achieving optimal potato growth, maximum yield, and high quality potato tubers. Generally, potatoes thrive well when fed fertilizers rich in nitrogen, phosphorus, and potassium as at when due. The Old Cobblers Farm’s Seed Potato Fertilizer is highly recommended for potatoes. I consider it the best, ahead of other fertilizers, because of its formulation. It contains nitrogen and is relatively high in phosphorus and potassium; these nutrients are crucial for large tuber development and healthy growth of the potatoes. Applying organic fertilizers like compost and manure is highly recommended, particularly during land preparation; they offer a sustainable option by improving the soil health and ensuring a safe environment while supplying the potatoes required nutrients for healthy growth.