Best Fertilizer For Irises Review & Application Guide

Did you know irises are named after the Greek goddess of the rainbow? Surprising as it is, irises have the finest-looking color gradient compared to most other flowers.

They also have a mesmerizing smell that will surely cheer you up. Which makes them the most competent garden flowers to grow.

Graceful as they are, they need a good amount of care to bloom at their finest. Proper care and picking the best fertilizer for irises will take a good amount of stress on your chest. Fertilizers go a long way to grow healthy-looking irises that smell good too.

With countless fertilizers available online, it is understandable for you to get overwhelmed. There are a variety of fertilizer types, each having their unique set of properties that acts situational. 

Before picking one up, you should first determine what is your end goal after applying the fertilizer.

Let’s discuss the primary types of fertilizer for irises to clear things up a bit-

What Fertilizer is for Growing and Blooming Iris?

The number of irises and its blossom size is on the rise which is resulting in new varieties. Compared to the old ones, newer varieties require more fertilizer to grow and bloom. This resulted in brands to produce multiple variances of plant food that appeals to your flower growing needs.

Best Fertilizer for Growing and Blooming Iris

Always make sure that the phosphorus and potassium count is higher compared to the nitrogen while shopping for flower food. Depending on your requirements, plant state, and growing season, fertilizer choice will vary greatly. Here are some fertilizers type that you might find useful for you irises-

Low Nitrogen Fertilizer

Fertilizers that are lower in nitrogen count are the right ones for growing irises as higher nitrogen in fertilizer leads to weak foliage and bacterial rot. Instead of making your flower healthier, they might backfire and harm your irises. Wouldn’t want your precious irises to rot, would you?

To have a better indication of what type of fertilizer is considered to be low in nitrogen, they are labeled accordingly. You will find NPK fertilizer labeled as 4-10-10, 5-10-10, and 6-10-10 to have better hindsight. These are by far the best type of fertilizers for growing irises.

Bone Meal

Stronger root and healthy stems are directly linked to better blooming for irises. Phosphorus is the most needed chemicals that trigger both of these in your irises and let them bloom at their best. Without a sufficient amount of phosphorus, your irises will give out signs of phosphorus deficiency as they turn purple or red.

This is where bone meal steps in as they are known to be an amazing source of phosphorus. This is what makes them act great as a plant fertilizer, especially for growing flowers. As irises rely greatly on its root, bone meal makes one of the best fertilizers for irises.

Bulb Fertilizer

Bulbs are referred to as the buds of your flower when they start to bloom during a blooming season. Newly planted bulbs need frequent feeding with specialize bulb foods that are high in phosphorous. Higher phosphorus promotes plant growth and these “Bulb Fertilizers” are highly recommended during a blooming season.

You will often see your iris bulbs to be fatter just before the next blooming season as they have been storing energy and food that will be needed later. Upon planting these bulbs, you need to feed them balanced fertilizer rich in phosphorus. These balanced fertilizers are often referred to as “Bulb fertilizer”.

Top 10 Best Fertilizer For Irises

Iris are generally planted in July to September. And the best time for fertilization is one month before they bloom in spring. For that purpose, the best fertilizer for growing Irises are low-nitrogen fertilizers (4-10-10 or 5-10-10 or 6-10-10). Besides, bone meal, fish fertilizers are also recommended for growing Iris flower plants.

Now, let’s dig -into the review…

  1. 6-10-10 Controlled Release Iris Food by Schreiner’s Iris Gardens

6-10-10 Controlled Release Iris Food by Schreiner's Iris Gardens

So far we have reviewed slow release and granular fertilizers for irises and we want you to know that controlled-release ones work quite well in giving you precise application. If you want to tweak growth or simply want your irises to look good, this fertilizer will come in handy.

Irises look best when the bloom at their finest. To achieve the maximum level of bloom, you need to feed your precious flower with quality food. And the Controlled Release Iris Food by Schreiner’s Iris Gardens is just the thing you need.

If you are struggling to maintain the look of your irises, boy do we have some bad news for you. Your flowers must be lacking the necessary nutrients to fight external conditions and climate stress which is tempering with its health. This fertilizer, however, will prove to be of great help by improving the health of your irises and strengthening it to fight off most external conditions.

This is a well-balanced iris fertilizer as it contains a minimum amount of nitrogen and a balanced amount of phosphorous and potassium that irises crave.

Key Features

  • Premium grade fertilizer for your irises to enjoy
  • Helps irises to bloom at their finest.
  • Promote greater health for irises.
  • Controlled-release fertilizer for precise application.
  1. Organics 9626 Bulb Granular Fertilizer, 4 lb by Jobe’s

Best Fertilizer For Growing Irises

If you are in for instant results, quick release fertilizers are the one which you should go for. And the 9626 Bulb Granular Fertilizer by Jobe’s sure does perform quicker than expected. This organic fertilizer is water-soluble, dissolves fast, and is quicker on releasing nitrogen and needed nutrients for your irises.

Now like most of the plants, irises don’t enjoy synthetic chemicals on its fertilizer. As most fertilizer promises to include organic ingredients in their mix, are they trustworthy though? The 9626 Bulb Granular Fertilizer, however, is OMRI listed, which means they are certified to not include any synthetic chemical on their fertilizer.

Jobe’s is a highly appreciated brand among gardeners, especially for the Biozome feature on their fertilizers. This feature does a splendid job in breaking down material at a much faster rate to promote greater growth for irises. Also, it creates a lively environment for plants by improving soil conditions and increasing insect resistance.

Amazing value for the price you pay indeed!

Key Features

  • Fast release fertilizer that ensures instant results.
  • Biozome feature ensures a healthy environment for plants to grow.
  • Contains zero synthetic chemicals
  • Certified by OMRI as 100% organic fertilizer.
  1. FX14049 Liquid Nutrient Trio Soil Formula by Fox Farm (3 Pack)

top liquid fertilizer for iris

Are you looking for a fertilizer that offers all in one solution? Most fertilizers available online offers a solution to specific problems that you might face while growing irises. On the other hand, FX14049 Liquid Nutrient comes in a pack of three that offer the right kind of juice for the right kind of use.

Irises need a lot (6 hours) of sun exposure to have the optimal growth rate. If you live in an area that has shady weather conditions or hard for your irises to get sun exposure, growing them will be a bit of a hassle. This is where the Grow Big Hydro might come in handy has it promotes abundant growth for your irises.

You might want to use the Tiger bloom to see greater flowering and bud set from your irises. These features make the fertilizer one of the best fertilizer for irises as it takes your irises to its peak flowering capability.

Lastly, Big Bloom works long term basis and will ensure stronger root development and nutrition supplement throughout the year.

Key Features

  • All in one best gardening solution that money can buy.
  • Comes in a pack of three to ensure greater growth, abundant flowering, and stronger root development.
  • Ideal fertilizer for growing flowers late season.
  1. Organics Bone Meal Fertilizer, 4 lb by Jobe’s

Organics Bone Meal Fertilizer, 4 lb by Jobe’s

Jobe’s is one of the remarkable brands for offering quality fertilizers for gardening. We have review one of their fertilizers already and here comes the second one. Now the Bone Meal Fertilizer of theirs offers a good source of calcium and phosphorus that irises enjoy a lot.

The perfect kind of fertilizer for growing irises is the 2-14-15 once as irises demand calcium and phosphorus a lot for greater bloom. Luckily, this fertilizer perfectly fits the shoe and promotes strong root development and plenty of blooms for your irises. This granular fertilizer ensures quick release as it is water-soluble.

Then again, we have the OMRI certification on this bad boy too to keep you worry-free. That’s right! No synthetic chemical and completely organic food for your precious irises.

Key Features

  • A tremendous source of phosphorus and calcium for growing irises.
  • Prilled fertilizer that reduces dust while applying.
  • 2-14-15 fertilizer that offers stronger root development and amazing bloom.
  • Sufficient fertilizer that offers nutrients supplement for an entire season.
  1. Alaska Morbloom Concentrate 0-10-10 Fish Fertilizer for Iris Plants

Alaska 022671700003 100099251 32 Oz Morbloom Concentrate 0-10-10

Did you know that fish remains acts as a superb source of nutrients for flowers? The skin, scales, and bones of dead fish are often converted into nutrients and they perform quite well too. Alaska Morbloom by Alaska is completely made of fish and is wonderful for growing irises.

While growing irises, your top priority should be on the blooming and budding of the flower. What is the point of growing irises if it doesn’t even bloom colorfully? Worry not as this fertilizer encourages greater blooming and budding from your irises to fill your garden with abundant colorful flowers.

Now, there is a hype on Alaska Fish Fertilizer as farmers are more interested on them.

On top of that, you can use this fertilizer for growing almost any kind of buds besides irises too. Mesmerize yourself with aromatic flowers in your garden or backyard with the help of this fertilizer. Not only will they smell good but also have a strong root that will sustain for a long period.

Key Features

  • Encourages to grow lavish blooming flowers.
  • Promotes sturdy root growth for your irises to be sustainable.
  • Completely made of fish and provides an organic supplement to plants.
  • Can be used to grow a wide range of flowers.
  1. BT18 Bulb Tone, 18-Pound by Espoma

BT18 Bulb Tone, 18-Pound by Espoma

This fertilizer by Espoma is an ideal one to be used to grow flowers during spring. Spring is the best time to grow elegant looking bulbs as this is the time where they reach peak growth rate. And with the help of this fertilizer, you will be filling your garden with heavenly smelling irises in no time.

With the blend of natural organics and rich bone meal, this fertilizer offers an effective balance between growth and bloom. Natural organics such as phosphorus boosts up plant development and durable root. While bone meal encourage plant to bloom at its peak.

Additionally, the bio-tone formula of this fertilizer is like a cherry on top. Bio-tone formula is well known for growing plants that can endure environmental stress, have deeper roots, and fast establishment. What else do you need to grow healthy-looking irises?

Besides growing irises, this fertilizer will come in handy for growing several different spring bulbs such as hyacinths and daffodils.

Key Features

  • The Bio-tone formula encourages the growth of the finest blossoms.
  • A splendid blend of natural organics and bone meal that offers balanced nourishment for your plants.
  • Durable fertilizer that supports sever seasons.
  • Ideal plant food for growing irises.
  1. Performance Organics Blooms Plant Nutrition Granules by Miracle-Gro

Performance Organics Blooms Plant Nutrition Granules by Miracle-Gro

If you like feeding your flower frequently instead of feeding once per season, you should consider picking this fertilizer up. This fertilizer grants decent results upon feeding your irises every 7 days. Kind of watching your child grow as you put little by little effort as you go along the way.

The effectivity of your fertilizer depends on the application of it to some extent. With proper tools and guidelines, you can apply your fertilizer the correct way and see the best result. To make your feeding effort more uplifting, this fertilizer comes with a garden feeder that makes the job quite fun.

You will be reassured to know that the fertilizer is OMRI listed. OMRI or Organic Materials Review Institute has certified this fertilizer to be 100% organic. Growing flowers that bloom profoundly and has vibrant color will be easier than ever with this fertilizer.

Key Features

  • OMRI listed flower food that shows a brilliant result.
  • Frequent plant food that performs well in growing vibrant looking flowers.
  • Miracle-Gro garden feeder for effortless and precise application.
  • Covers wide (265.sq.ft) soil area to ensure your plant gets every bit of nutrients that it needs.
  1. EarthPods Premium Bloom Flowering Plant Food – Easy Organic Fertilizer Spikes

EarthPods Premium Bloom Flowering Easy Organic Fertilizer Spikes

Applying fertilizer can be quite a messy job as most of them also contain the intolerable smell. Not with this one though as it has no smell and needs no measuring thanks to the pod design of this fertilizer. 1 tube contains about 100 earth pods that will be sufficient enough for at least 4 years of nutrition supply. 

Premium fertilizer acts for both indoor and outdoor gardening. Whether you choose to decorate your living room with sophisticated smelling flowers or fill your garden with tons of blooming ones, this fertilizer will be glad to help. Besides growing irises, you will find this fertilizer helpful for growing diverse sets of flowers as well.

Are these earth pods ecofriendly though? You bet they are! These minimalistic earth pods are quite easy to store thanks to their compact design and are less likely to put any harm to your kids and/or pets. When you are done applying them, you can even recycle the empty paperboard tube that it comes in.

Key Features

  • Premium fertilizer that works for both indoor and outdoor growing.
  • Minimalistic design that offers stress-free and firm application.
  • High-performance fertilizer filled with trace minerals and natural soil hamates that gives an optimum result.
  1. Bulb & Bloom Food 4-10-10 4lb for Iris by Lilly Miller

Bulb & Bloom Food 4-10-10 4lb for Iris by Lilly Miller

You should know that irises enjoy less nitrogen, unlike those acid-loving house plants. A fertilizer that is rich with potassium and phosphorus is the best one for growing irises as the flower requires these nutrients at plenty to grow. Thankfully, the Bulb & Bloom Food fertilizer by Lilly Miller has a ratio of 4-10-10 that is the perfect balance for growing irises.

The fertilizer is slow release in type and will supply nutrients as you water your irises frequently. Just apply it and you will be all set. You won’t even have to worry about feeding your flower too often as frequent watering will do the trick for you.

Lilly Miller is a quite popular brand among gardeners and they have been known to provide promising fertilizer. If you are overwhelmed with all these fertilizers, you can put your trust in this fertilizer as it won’t disappoint you. With 4lb of it, you will find it sufficient for multiple growing seasons to come.

Key Features

  • Perfectly balanced fertilizer for growing irises.
  • Slow-release fertilizer that keeps feeding your plant as you water it.
  • Promising fertilizer that will produce the desired result.
  1. Bulb Continuous Release Plant Food, 3-Pound by Scotts

Bulb Continuous Release Food for Iris Plants

If you are looking for long-lasting plant food that gives stunning color from your irises, you can count on this fertilizer by Scotts. This fertilizer is likely to last for at least 1 season (2 months) and will promote greater bloom from your irises. All you need to do is apply it frequently.

Whether you decide to use it on newly planted flowers or flowers that are already established, it will give you the desired result in both cases.

This all-purpose fertilizer will be with you throughout multiple seasons and will perform at its maximum. At this price point, this is an amazing buy.

This fertilizer is the perfect blend of the three most desired nutrient chemicals that your plant needs to grow abundantly. It has a 10-12-10 composition which is a balanced mix and slightly higher phosphorus as irises enjoy phosphorus much.

Key Features

  • Decent fertilizer that lasts for an entire season.
  • Require less effort while applying thanks to its simple design.
  • Feeds both newly planted or established bulbs with much-needed nutrients.
  • A perfect mixture of organic chemicals with a slightly high phosphorus rate.
  • Great value for the price you pay.

When and How to Apply Fertilizer?

You need to start preparation about 6 to 8 weeks before the blooming season that is early spring to be precise. Feeding your plant at an earlier stage will better prepare it for the blooming season as it will grow at its fullest during that time. As for the fertilizer type, you should go with the one that has the highest level of phosphorus.

Phosphorus is much needed during the earlier stage of the bulb as they promote growth and root development. We recommend that you use bone meal or balanced bulb fertilizers that are available online.

These fertilizers are rich in phosphorous and will promote greater blooming when the times come. When picking fertilizer up for your irises, always pick the one that has the lowest level of nitrogen.

Before applying soil, testing it would be the smartest thing you can do to avoid long term problems of your irises. You can even save your irises from premature death due to an unbalanced amount of chemical present in the soil. The areas you should look for are whether the pH level is 6.5 to 6.8 or not while keeping the nitrogen level to a minimum.

If everything checks out, you can safely apply fertilizer in your soil.

Tips on Applying Fertilizer:

As we have said earlier, irises grow comfortably in a soil that has a pH level between 6.5 to 6.8. These are the optimal level as irises will be able to take in the most nutrients that they possibly can from the soil. Resulting in better growth and abundant blooming.

  • We have said it before and we are saying it now, test your soil people. Testing is the only way to be sure that your soil is holding the correct pH level and the lowest amount of nitrogen which is harmful to irises.
  • You will find soil kits in hardware stores or garden supplies store at an affordable price. Worth the investment and you are less likely to regret.
  • As fertilizer lists what kind of balance they are carrying of nitrogen, phosphorus, and potassium you will find picking the right one easier.
  • Remember people, high phosphorus means the stronger root of your irises which results in plentiful blooming. While potassium assists to survive against environmental harm and fight of winter stress.

Although nitrogen helps with green growth and lush foliage, it is not necessary for irises. Especially during fall. During this time, your best bet is to use bone meal or bulb fertilizer that contains no nitrogen and has a balanced level of phosphorus. The 0-10-10 are a good place to start.

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Final Words

Malnourished bulbs will have weaker stems that will make it hard for them to emerge through heavily mulched ground covers. If they are weaker at the blooming stage, what chance they have when they grow at their fullest?  Fertilizer is much needed and they are the vital source of nutrition supplements.

With the best fertilizer for irises at hand, you can ensure the optimum growth of your precious bulbs. Soil often lack the needed nutrients that are essential to growing irises. This is where fertilizers step in as they are specialize to provide certain types of chemicals for the right kind of plant.

So what are you waiting for? At this point, you should have enough knowledge about fertilizer types and what appeals to be the best fertilizer for irises. We have also reviewed some of the best fertilizer products online from where you might pick one that fits your purpose best. Good luck!

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