10 Best Fertilizer For Petunias 2022 [Reviews & Guide]

Petunias are always hungry, especially during the flowering period. They need the perfect food at that time. Why?

Well, Petunias come up with new blooms every 2 or 3 days during summer. And it takes a high amount of energy to produce back-to-back flowers.

But here’s an issue. Whenever we look for Petunia fertilizer, we start thinking, what is the perfect fertilizer for Petunia?

In Short, any fertilizer that supplies both macro & micronutrients and ensures instant & long-term feeding is primarily perfect for Petunias.

But wait, the fertilizer requirements may vary according to the soil quality, Petunia variety, season, age & so on. And that’s why growers often get confused about which one to buy.

But don’t worry. Keeping all this in mind, this article presents to you, the 10 best fertilizers for Petunias. I hope my in-depth research comes in handy for you. Let’s check them out.

Top 10 Fertilizer For Petunias- Comparisons

J R Peters Jack's Classic Petunia Feed20-6-22GranularSynthetic
Miracle-Gro Bloom Booster Flower Food15-30-15GranularSynthetic
Dr. Earth Flower Garden Fertilizer3-7-4GranularOrganic
Osmocote Smart Release Plant Food15-9-12GranularSynthetic
Proven Winner Water-Soluble Fertilizer24-12-17GranularSynthetic
Jobe’s Container & Bedding Plant Fertilizer3-5-6SpikesOrganic
Jobe’s Hanging Baskets & Potted Plants Fertilizer8-9-12SpikesSynthetic
Miracle-Gro All-Purpose Plant Food12-4-8GranularSemi Organic
Triple 10 All-Purpose Fertilizer10-10-10LiquidSemi Organic
Southern Ag All-Purpose Fertilizer10-10-10GranularSynthetic

Top 10 Fertilizer For Petunias- Reviews

1. JR Peters Inc Jack’s Classic Petunia Feed

J R Peters Inc 52624 Jacks Classic No.1.5 20-6-22 Petunia Feed

My first recommendation is a uniquely made fertilizer for Petunias. It is manufactured by JR Peters Inc – a professional plant food maker company & renowned for its specially blended water-soluble fertilizers. Let’s see how special it is-

Nutrient Composition

The fertilizer comprises macro & micronutrients collected from inorganic sources like urea, ammonium sulfate, monopotassium phosphate, iron EDTA, copper EDTA & so on.

However, the nutrient composition is quite enriched. The NPK ratio is 20-6-22. That means N adds 20% of the packet weight while P & K adds 6% & 22% respectively. Along with these, the fertilizer also contains other macro & micronutrients, such as Mg (1%), B (0.02%), Co (0.05%), Fe (0.20%), Mn (0.05%), Mo (0.0009%) & Zn (0.05%).

Nutrient Analysis

You know, Petunias require high N & K during the first year for strong root establishment & growth. Well, with such an NPK ratio, this fertilizer seems one of the best for Petunia seedlings.

The low percentage of phosphorus may tense you a little bit. But don’t worry. I have calculated that, for each application, your inground Petunias will get around 0.13g Phosphorus. And guess what, a study of North Carolina University over Petunias says such an amount of phosphorus is quite okay.

Exclusive Highlights

Though it is Petunia feed, you can also use it for Bacopa, Vinca, Rhododendron, Snapdragon, Pansy & such others. Moreover, it takes care of Iron hungry plants like Petunias as they can’t tolerate iron deficiency & causes chlorosis.

You will notice that Fe, Cu, Mn & Zn are present in chelated form which means these nutrients are combined with an organic matter called chelate & chelate ensures 24/7 availability of these nutrients at the root zone.

However, you know, potted or hanging Petunias need more N & K than the ground ones because of limited soil. Good news- expert growers find this the ideal fertilizer for potted or hanging basket Petunias.

Application Method

Whenever you water, add the fertilizer following the 1 teaspoon/gallon ratio. That would be all.


2. Miracle-Gro Water-Soluble Bloom Booster Flower Food

Miracle-Gro, 1-Pound 1360011 Water Soluble Bloom Booster Flower Food

Miracle-Gro Water Soluble Bloom Booster is a popular fertilizer among flower growers. Its polished Nutrient composition addresses it as the best water-soluble fertilizer for Petunias.

Nutrient Composition

The fertilizer derived all its nutrients from safe & non-toxic inorganic origins. It contains both macronutrients (required in higher amount) – N (15%), P (30%) & K (15%) & micronutrients (required in lower amount) – B (0.02%), Cu (0.07%), Fe (0.15%), Mn (0.05%), Mo (0.0005%) & Zn (0.06%).

Nutrient Analysis

The most noticeable part is the high amount of phosphorus. You know, any flowering plant thrives for phosphorus as it is directly involved in blooming & that’s why it is a bloom booster.

Interestingly, the fertilizer contains N from two sources- ammoniacal nitrogen (5.8%) & Urea Nitrogen (9.2%). You may ask, why? It is because Petunias can uptake N in two forms (NH4+ & NO3-) & both forms are available for optimum uptake.

Exclusive Highlights

As the bloom booster is water-soluble, it will feed your hungry Petunias instantly. It also carries chelated Iron & Manganese so that the nutrients remain in available form & your Petunia can uptake easily.

Applying Procedure

For inground Petunias, the mixing ratio is 1½ tablespoons per 6 liters of water. After that, spray the solution around the base equally. Wait, don’t forget to re-apply after 7-14 days.


3. Dr. Earth Organic Flower Garden Fertilizer

Dr. Earth 705P Organic 6 Flower Garden Fertilizer

“We harvest the nutrients from today’s food scraps to create organic fertilizers and soils that will grow tomorrow’s food”- Dr. Earth Company seems truly confident about their organic sources. I think that’s why the fertilizer is OMRI, OIM, CCOF & NOP approved. Let’s see what else it has-

Nutrient Composition

The NPK ratio of the fertilizer is 3-7-4 & the nutrient sources are fishbone meal, alfalfa meal, rock phosphate, potassium sulfate, bone meal, feather meal & kelp flour.

Interestingly, there is no indication of other macro or micronutrients in the packet label, but my research says the fertilizer also adds calcium, phosphorus, iron, magnesium, zinc, sulfur & Sodium to the soil.

Nutrient Analysis

Well, let’s start with N. Surprisingly, all 3% of the nitrogen is water-insoluble & which ensures slow release of N for up to one month. Moreover, it has a high phosphorus content to stimulate the bud development of your Petunias.

Exclusive Highlights

Users of this fertilizer have found it useful for maximum Petunia varieties like Mexican Petunias, Waving Petunias, Night sky, Black Velvet, Petunia Bravo, Cascadia Petunia, Prism Petunia, Pink Star Charm, Shock Wave & so on.

Good thing is- the fertilizer also comes in handy in the case of other flowering plants, such as Inpatients, Geraniums, Marigolds, Begonias, Lavender, Daylilies, etc.

Notably, it contains TurBiotic- a special blend of beneficial soil inoculants like soil microbes & Mycorrhizal fungi. These colony-forming units bring life to the soil by improving its organic matter content & overall quality.

And additionally, the fertilizer carries 10% humic acid. You know, Humic acid works as chelates & improves the nutrient uptake quantity of your Petunias. Moreover, it enhances drought tolerance, root growth & soil microbial activity.

Finally, with such an enriched formula, I think this fertilizer is the answer to this very common question of many gardeners- “What is the perfect natural fertilizer for Petunia?”

Applying Method

Sprinkle 4 tablespoons of fertilizer on the soil of a 12″ Petunia container. After slight soil work, water thoroughly & keep applying once a month throughout the growing season.


4. Osmocote Smart Release Plant Food

Osmocote Smart-Release Plant Food Plus Outdoor & Indoor

Scotts Miracle-Gro Company has manufactured this advanced premium quality fertilizer. The product label says it is a smart release fertilizer for petunias. Interesting, right? Let’s see-

Nutrient Composition

The fertilizer supplies a total of 11 essential nutrients & they are- 15% N, 9% P, 12% K, 1.3% Mg, 6% S, 0.02% B, 0.46% Fe, 0.06% Mn, 0.02% Mo & 0.05% Zn.

And for your interest, all these nutrients are obtained from polymer-coated safe inorganic sources.

Nutrient Analysis

It is a unique nutrient composition as every granule is coated with semi-permeable resin & gets dissolved slowly to feed your Petunias for up to 6 months. That’s why it is the recommended time-release fertilizer for petunias.

However, the followings are the slow-releasing percentages of the nutrients- 12.7% N, 7.6% P, 10.2% K, 1.1% Mg, 5.1% S, 0.015% B, 0.35% Fe, 0.05% Mn, 0.015% Mo & 0.015% Zn.

You can see that most of the nutrient percentage is slowly releasing but your Petunias will get some instant food too. Isn’t it a great combination?

Exclusive Highlights

The fertilizer contains 0.01% chelated Iron to combat the iron chlorosis of Petunias.

Applying Method

Sprinkle the fertilizer over the container soil. The exact dose is 3 tablespoons per 2 gallons of soil. After that, water thoroughly.


5. Proven Winner Premium Water-Soluble Fertilizer

Proven Winner Water-Soluble Fertilizer

Petunias are heavy flowering & fast-growing plants. Within two or three months, the pot or basket gets totally covered with heavy foliage & abundant blooms. And guess what? This plant food is precisely made to feed such first growers.

Nutrient Composition

The fertilizer bears 10 essential nutrients of inorganic origin, such as ammonium phosphate, potassium nitrate, magnesium sulfate, urea, copper EDTA, etc.

And the nutrients are- N (24%), P (12%), K (17%), Mg (0.60%), B (0.024%), Cu (0.05%), Fe (0.12%), Mn (0.06%), Mo (0.018%) & Zn (0.05%).

Nutrient Analysis

The NPK ratio is just perfect for potted or hanging basket Petunias to ensure proper root growth, green foliage, abundant blooms & available nutrition.

However, the fertilizer contains N from 3 sources. All these sources supply N continuously but not together. As a result, your Petunias get N constantly.

Moreover, this water-soluble fertilizer feeds your Petunias instantly & ensures easy nutrient uptake.

Exclusive Highlights

You may notice, the fertilizer contains chelated Cu, Fe, Mn & Zn. Thus the fertilizer avoids injurious reactions & secures a continuous supply of these nutrients for the next one or two weeks.

Applying Method

For your outdoor 10″ potted Petunias, drench the soil with a half-gallon of Proven Winner plant food solution. The mixing ratio is one tablespoon per gallon of water & re-apply after 7-14 days.


6. Jobe’s Organics Container & Bedding Plant Fertilizer Spikes

Jobe’s Organics Container & Bedding Plant Fertilizer SpikesIf you are looking for the best organic spike fertilizer for your potted or ground Petunias, this is probably the one. Follow me to know more-

Nutrient Composition

The fertilizer is OMRI approved as all three nutrient sources (feather meal, bone meal, sulfate of potash) are 100% organic & natural.

However, the product label says it contains 3% N, 5% P & 6% K. But my research says the sources supply some other essential nutrients too.

Nutrient Analysis

Among 3% of N, 1.2% of it is water-insoluble. You know, water-insoluble nutrients release slowly to get uptaken by plants. Thereby, you get relieved from thinking about N deficiency for the next 6-8 months.

Anyway, bone meal, feather meal & sulfate of potash works for robust Petunia blooms, root growth, nutrient absorption & some other important internal mechanisms like respiration, transpiration, etc.

Exclusive Highlights

Along with Petunias, this kid & pet-friendly fertilizer will take care of all your flowering & foliar plants.

The best thing is, as it is a spike fertilizer, no waste or runoff is guaranteed. Moreover, Jobe’s special spike formulation increases soil microbial activity to keep the soil fertile & well-drained.

Applying Method

For 12″ potted Petunias, push 8 spikes against the soil following the pot edges. After that, water thoroughly and re-apply fresh spikes after 8 weeks.


7. Jobe’s Hanging Baskets & Potted Plants Fertilizer Spikes

Jobe’s Hanging Baskets & Potted Plants Fertilizer SpikesI have come up with another Jobe’s product & it is also a spike fertilizer. But this time, it is an inorganic fertilizer.

Nutrient Composition

Don’t get me wrong but I think Petunias look more attractive in pots or hanging baskets than ground ones. And this fertilizer comes up with a stable nutrient composition for pots or baskets.

The NPK ratio is 8-9-12 & the nutrient sources are ammonium sulfate, ammonium phosphate, potassium nitrate & potassium sulfate & chlorine.

Nutrient Analysis

You know, it is difficult to fertilize frequently in pots or containers, especially in the case of Petunias because they cover the whole pot with leaves & flowers.

Keeping that in mind, the company ensured a high percentage of occluded nutrients. You know, occluded nutrients release slowly for a long time and thus the fertilizer feeds your Petunias for up to 8 weeks.

For your concern, the occluded nutrient percentages are- 6% N, 6.6% P & 8.4% K.

Exclusive Highlights

The spikes are formulated with Jobe’s Biozome- a special blend of healthy bacteria, Mycorrhizal fungi, and Archaea. It increases the long-term soil quality, growth and helps your Petunias to combat disease, insects & drought.

And also, pre-measured spikes ensure no waste or runoff & supply exactly what your Petunias need.

Applying Method

2 spikes are enough for a 12″ Petunia pot. Push the spikes evenly at the edges of the pot & then water thoroughly.


8. Miracle-Gro Shake ‘N Feed All-Purpose Plant Food

Miracle-Gro Shake 'N Feed All Purpose Plant Food

All-purpose fertilizer is an easy solution for your garden. It relieves you from individual research & a certain amount of money too. Keeping that in mind, I have included this Miracle-gro fertilizer for your Petunias. Give it a look-

Nutrient Composition

First I want you to look at the nutrient sources- urea, ammonium phosphate, feather meal, kelp meal, potassium sulfate, copper oxide, earthworm castings, zinc sulfate & so on.

Interestingly, the nutrients are from both organic & inorganic sources & which makes it a semi-organic fertilizer.

Anyway, the fertilizer supplies both macro & Micronutrients for your Petunias. The nutrients are- N (12%), P (4%), K (8%), Ca (7.6%), Mg (2.5%), S (3.2%), Cu (0.06%), Fe(0.95%), Mn(0.35%) & Zn(0.02%).

Nutrient Analysis

Among 12% of N, 8.6% of it is slow-release nitrogen collected from polymer-coated urea & water-insoluble nitrogen from feather meal. And that tells you to stop worrying about the growth of Petunias because that amount of N will look after your Petunias for up to 3 months

The rest of the nutrients are water-soluble, which ensures an instant supply of 10 macro & micronutrients to feed your hungry Petunias.

Exclusive Highlights

The fertilizer takes care of both your Petunia & its soil. It contains natural ingredients to feed soil microbes. You know, soil microbes are necessary for the breakdown of organic matter & proper soil drainage. And thereby, the soil turns into a better host for your Petunias.

Applying Method

Shake the fertilizer over the soil of your pot. The dose is 3 tablespoons for a 10″ diameter pot. After that, slightly work on it & water thoroughly.


9. Triple 10 All-Purpose Liquid Fertilizer

Triple 10 All-Purpose Liquid FertilizerThis is my first liquid fertilizer recommendation for you. Though it is an all-purpose fertilizer, I think it is one of the best liquid fertilizers for Petunia because of its nutrient composition & user-friendly technique.

Nutrient Composition

The triple 10 means 10-10-10. It refers to the NPK ratio of the fertilizer that means it contains 10% N, 10% P & 10% K.

And these nutrients are derived from both organic & inorganic sources, such as urea, phosphoric acid, potassium hydroxide, amino acid & seaweed extract.

Nutrient Analysis

As you see, it is a balanced fertilizer because of the equal amount of N, P & K. 10-10-10 ratio is scientifically considered to be the safest for plants to secure high yield & it also checks fertilizer burn for Petunias.

Moreover, its liquid formulation supplies nutrients instantly & abundantly to your Petunias & feeds them for up to 14 days.

Exclusive Highlights

The fertilizer contains 5.5% amino acid that increases the nitrogen content of the soil. It aids your Petunias by promoting hormonal activity and synthesis resulting in abundant flowering.

Furthermore, seaweed extract is another attraction of this fertilizer. It promotes the growth of your Petunias & deters insects and diseases.

Applying Method

First of all, shake properly. After that, add 2 ounces of the fertilizer into 1 gallon of water & drench the soil like watering. Re-apply it after 2 weeks.


10. Southern Ag All-Purpose Granular Fertilizer


Southern Ag All-Purpose Granular FertilizerMy last recommendation is an all-purpose fertilizer too. The fertilizer is a product of Southern Agricultural Insecticides Inc. – a renowned plant food maker & distributor. Let’s see what this product contains-

Nutrient Composition

The fertilizer provides 9 essential macro & micronutrients to your Petunias- N (10%), P (10%), K (10%), Mg (2%), B (0.200%), Fe (0.500%), Mn (0.250%), Zn (0.250%) & Cl (note more than 1%).

And all these nutrients are derived from inorganic sources, such as Sulfate of Potash Magnesium, Ammonium Phosphate, Polymer-Coated Urea, Iron Sulfate, Protein Hydrolysate, Iron Humate, etc.

Nutrient Analysis

Like the previous one, it is also a balanced fertilizer that ensures proper & safe growth of Petunias. Additionally, it contains 5.56 % slowly available nitrogen from polymer-coated urea to feed your Petunias for up to 4 months.

Exclusive Highlights

The fertilizer bears iron Humate, a chelated form of iron. It ensures continuous availability of iron to check chlorosis & also reduces the chances of unwanted reaction into the soil.

Furthermore, it also contains protein hydrolysate- a source of amino acids. And as I said earlier, amino acids promote hormonal activity and synthesis for plentiful blooming.

Applying Method

For a 50 sq. ft. Petunia bed, sprinkle 1 cup of the fertilizer & then water thoroughly.


What Do I Feed Petunias

Petunias flower in pot

You know, every plant needs “Essential Nutrients” to complete its life cycle. And that’s what all the fertilizers contain to feed your Petunias.

Now you may ask, what nutrients do petunias need? Well, there are 18 essential nutrients in plant science & Petunias need all of them. But the good news is, Petunias naturally get some nutrients from the air, water, and soil.

However, joint research of some well-known universities shows that Petunias frequently fall in deficiency of following nutrients-N, P, K, Ca, Mg, S, Fe, Mn, Zn, Co, B & Mo. So, if you are thinking about Petunia fertilizer requirements, keep this in mind. But wait, there are two more things I want you to remember-

  1. Fe & Mg deficiency hurts Petunias pretty hard with severe chlorosis &
  2. Petunias like low soil pH. So, you might want to add some organic matter to the soil too.

How to Choose The Perfect Fertilizer for Petunias

Before choosing the perfect fertilizer, you have to go through a couple of factors. But don’t worry. I am here to walk with you throughout the entire process. Let’s start-

Knowing the requirements of your Petunia

Here are some issues you should know-

  1. Spreading-type varieties like Wave Petunias need weekly fertilization while most other types like Grandiflora or Multiflora need monthly fertilization.
  2. Seed propagated Petunias require less Nitrogen content than cutting propagated Petunias.
  3. During the first year, Petunias require high Nitrogen & potassium, while a phosphorus-rich fertilizer works well during the blooming period,

Wait, don’t get messed up. All I want to say is that fertilizer requirement fluctuates according to Petunia varieties, propagative origin, age & such others. That’s why you must know about your Petunia variety, its requirements & what nutrients your soil is lacking.

Here is a tip– test your garden soil yearly for the right decisions.

How To Choose the perfect fertilizer for Petunias

Once you know what your Petunias need then, ask yourself the following questions to pick the precise one-

Organic or Synthetic

Nowadays, organic gardening is very popular among gardeners because it is eco-friendly & the nutrients are from natural sources.

However, my suggestion is- do not choose organic fertilizers over a poor nutrient composition.  Whether the fertilizer is organic or synthetic, meeting your Petunia’s needs should be the priority.

Granular, Liquid, or Spike

This decision is totally up to you. If you like working with soil frequently, go for granular fertilizers. But if you are good with spraying, pick liquid ones. And normally, gardeners who face a hard time fertilizing timely, use spike fertilizers.

But wait, here are some other issues I want you to remember

  • Granular fertilizers are best for soil preparation before planting your Petunia &
  • Experienced gardeners say liquid fertilizers are good for potted or hanging basket Petunias

Special Features

Many fertilizers offer additional non-plant food material to improve the soil quality & nutrient uptake mechanism. It is better to choose a fertilizer that takes care of both below and above-ground parts of Petunias.

When Should You Fertilize Petunias

blooming Petunias

Petunia growers can be successful only when it is hard to identify green foliage due to abundant blooms.

You know, Petunias are mainly summer flowers. They start blooming in late spring & keep flowering until the first frost of autumn. And that’s why growers start fertilizing during early spring to give the blooming a head start.

How Often Can You Fertilize Petunias

Petunias Fertilizing Process

Normally, on average, Petunias need fertilizers every two weeks but it is better to stick to the direction of the fertilizer you are using.

However, the fertilizer requirement varies according to the Petunia Cultivar & soil quality. But by & large, Petunia needs fertilizer pretty often. Why?

Well, Petunias bloom more frequently. You may notice new flowers every two days. And it takes high energy to come up with bountiful flowers almost every day. That’s why they need fertilizer more often.

Best Homemade Fertilizer For Petunias

Homemade Fertilizer For Petunias with Mustard Cake

Petunias are common flowers in our garden & their popularity makes researchers study them way more than other flowers. However, when it comes to the best DIY Petunia fertilizer, several researchers have found a particular recipe most effective. And here it is-

Required Ingredients

  1. Mustard Cake-500g
  2. Water-10 L

Making Method

  1. Take 5L plain water in a bucket & add 500g mustard cake into it. After adding, stir it well.
  2. Cover the bucket and leave it for four days for the fermentation process. And remember to stir the mixture at least twice a day.
  3. After four days, take 500 ml of the liquid mixture & mix it with 5L of water. For proper mixing, stir it well.

And there you go. You have made an easy & effective fertilizer for blooming plants like Petunia.

Applying Method

For every Petunia plant, apply 100 ml of the mixture & water thoroughly. You may have to reapply in 15 days.

How To Get Petunias to Bloom More?

blooming petunias

 There are plenty of factors that may restrict your Petunia from abundant blooming, but here I am quoting three most effective ways to get more petunia blooms

  1. Make sure your Petunias are getting 5-6 hours of direct sunlight daily.
  2. Cut or pinch out the dead or wilted seeming flowers &
  3. Use a phosphorus-rich fertilizer or bloom booster before the blooming season.

Frequently Asked Questions

Is Miracle-Gro Good for petunias?

Both Miracle-Gro Bloom Booster & Shake ‘N Feed All-purpose plant food are good for Petunias. While the Bloom booster ensures abundant blooms in a short time, Shake ‘N Feed looks after your Petunias for up to three months & also improves soil quality.

Are coffee grounds good for petunias?

Using Coffee Grounds as fertilizer is the best example of home waste management. It supplies Potassium, Magnesium & phosphorus to the soil & feeds Petunias for abundant blooming.

Can you use Epsom salt on petunias?

Petunias often face magnesium chlorosis & result in stunted growth & poor blooming. But don’t worry. The right dose of Epsom salt will fight for you.

How often do you water petunias in hanging baskets?

The watering thumb rule for the hanging basket is – Water only when topsoils are dry. So, water your Hanging Petunias following the thumb rule. But generally, Petunia growers water daily during summer. And sometimes even twice during extreme hot & strong winds.

Is bone meal good for Petunia?

You know, petunias require phosphorus to bloom abundantly. And guess what? Bone meal supplies a handsome amount of phosphorus, for example- most bone meal’s NPK ratio is 3-15-0. Moreover, it also supplies calcium, iron, magnesium, zinc & some other nutrients.


Petunias are an illusion to our eyes. Their mesmerizing beauty is not easily comparable. But as I said, “Perfect bloom needs perfect fertilizer.”

And that’s why I kept searching for the perfect one & ultimately came up with these 10 best fertilizers for your Petunias. Now it is your turn to pick the right one.

I hope any of my recommendations may keep your ground or pot covered with amazing Petunia blooms. Happy Gardening.

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