Top 10 Orchid Fertilizers: A Comprehensive Review (2024)

Ever felt confused about finding the best fertilizer for your orchids among the plethora of brands, formulas, and formats in the market?  What is the difference between the 20-20-20 NPK ratio and the MSU formula?  Which is better: water-soluble granular orchid food, liquid fertilizer, ready-to-spray mist bottles, and slow-release pellets? 

Based on the nutritional needs of orchids, we have done a comprehensive comparison of the 10 most popular orchid food in the market in the year 2024.

The products will be listed in descending order according to the overall rating, based on their ingredients and cost.

We hope that this review will help you decide the best one for your orchid’s growing needs.

Quick Summary

• The best fertilizer is the MSU formula manufactured by Greencare and distributed and repackaged by “Tezula plants” and “rePotme”.  The contents in both products are basically the same, i.e. 13-3-15 NPK ratio, urea-free nitrogen for immediate uptake, and have all the macro and micronutrients with a high concentration in Calcium and Magnesium necessary for new growths and healthy orchid development. 
• The Editor’s Pick is the MSU fertilizer packaged by “Tezula plants” which is cheaper than the more well-known “rePotme”. 
• While the Tezula and rePotme MSU fertilizers are considered excellent, the “Sun Bulb” Better-Gro fertilizer (30-10-10) can be considered good.  Better Gro has a rather comprehensive nutritional profile, reasonably priced but lacks Calcium, and is low on Magnesium.  It may be okay for use with tap water high in Calcium.  Or else, it would need to supplement with a Cal Mag fertilizer which can be inconvenient having to mix two fertilizers in each watering and be careful with the measurement to not over-fertilize. 
• The cheapest fertilizer is “Miracle Gro” (20-20-20) which costs only a fraction of the price.  But it comes with the cost of paying for a mediocre orchid fertilizer that is not urea-free and is not transparent about its nutrient contents if they ever exist.
• Finally, fertilizers in water-soluble, granular form are more cost-effective than liquid and ready-to-use fertilizers.
• But for those with only 1 or 2 orchids to feed, liquid fertilizers are better because the granular ones could clump into one big piece of hard rock with the entry of humidity and thus would not be usable after a year.

1. Best Orchid Fertilizers For Healthy Growth and Blooming

1.1 “Tezula Plants” MSU Fertilizer (13-3-15) – Editor’s Pick

Verdict: 5 stars

“Tezula plants” is a reputable nursery in Florida and one of the distributors of the MSU fertilizer manufactured by “Greencare” fertilizers of Kankakee IL.  In fact, just about everyone who sells MSU formula for orchids gets it from “Greencare”. 

The fertilizer is hand-coated in a blue or green dye that will give the liquid fertilizer a light blue color when you mix it in water. The color will fade naturally over time (1-2 years), but the mineral contents are not altered.

Nutrient profile:    

• NPK ratio: 13-3-15
• It uses the renowned Michigan State University (MSU) formula which is urea-free or nitrate-based nitrogen for immediate uptake by the roots. 
• It offers a complete nutritional profile with macro and micronutrients (Iron 0.177%, Manganese 0.088%, Zinc 0.044%, Copper 0.044%, Boron 0.018%, Molybdenum 0.018%). 
• It is also low on Potassium (NPK ratio: 13-3.7-15.9) and high on Calcium 8% and Magnesium 2.6%.       

Cost:

The fertilizer is packaged in 3 formats: 8oz ($10.09), 1lb ($16.99) and 2 lbs ($21.99).

Following the recommendation of dissolving 1 tsp of the granular fertilizer in 1 gallon of water, the three formats can make 54.5 gallons, 109 gallons, and 218 gallons of liquid fertilizer respectively.

Therefore, the cost to feed orchids using Tezula plants MSU fertilizer is $0.18/gallon (for 8oz), $0.15/gallon (for 1 lb), and $0.1/gallon (for 2 lb) respectively.

To learn more about what the MSU formula is, scroll down to part 4 below.

1.2 “rePotme” FeedMe! MSU Fertilizer (13-3.7-15.9)

Verdict: 5 stars.

This is basically the same MSU fertilizer as the one packaged by Tezula Plants but is more expensive when it is sold by rePotme which is a more well-known brand.

Nutrient profile:  The contents of this product are basically the same as the “Tezula plants” MSU fertilizer and thus have the same nutrient profile as theirs.

Cost:  Following the manufacturer’s recommendation of dissolving 3/4 tsp of the granular fertilizer in 1 gallon of water, the 8 oz (227g) and 1 lb formats respectively cost $19.99 and $30.55 and make 64 and 136 gallons of liquid fertilizer. 

Therefore, it costs $0.31 per gallon (for 8oz) and $0.21 per gallon (for 1 lb) of liquid fertilizer for feeding your orchids. 

1.3 “Better-Gro” (20-14-13)

Verdict: 4.5

• Water soluble, Granular form

Nutrient profile: 

• NPK ratio: 20-14-13
• It is similar to the popular Michigan State University (MSU) formula with 10.59% of nitrate nitrogen for immediate uptake by the roots. 
• It contains also the important macronutrient of Magnesium (1%).
• The proportions of micronutrients are very similar to the MSU formula with Iron 0.2%, Manganese 0.05%, Zinc 0.05%, Copper 0.05%, Boron 0.02%, Molybdenum 0.0005%).

The only drawback is that it does not contain Calcium which is important for cell development in new growths.  Some people have reported that this shortcoming would not matter to them because their tap water has enough Calcium or they combine it with a Cal-Mag fertilizer.

Many people have reported success with bigger and longer blooms, new growths, stronger roots, and leaves, etc. not only with their orchids but also their flowers and plants in the garden.     

Cost:  This fertilizer is the cheapest amongst the fertilizers reviewed. However, it would cost the same as “rePotme MSU Fertilizer” (Editor’s Pick) if it requires a separate purchase of a Cal-Mag fertilizer. 

Following the manufacturer’s recommendation of dissolving 1 tsp of fertilizer in 1 gallon of water, the 16 oz (0.45 kg) bag of fertilizer in granular form costs only $10.68 and can make 96 gallons of liquid fertilizer.  It thus costs only $0.11 per gallon of liquid fertilizer for feeding your orchids. 

1.4 “General Hydroponics” Cal-Mag  – Best Orchid supplement 

Verdict: 5 stars

Nutritional profile:

NPK ratio: 1-0-0, 5% Calcium and 1.5% Magnesium

For those who did not use a complete fertilizer like the MSU formula by rePotme.  They would also need to purchase a Cal-Mag fertilizer to give Calcium and Magnesium supplements to prevent die-off and root burns.

Cost: Makes 192 gallons of liquid fertilizer

Cost of fertilizer produced: $0.09gallon

1.5  “JR Peters/Jacks” (7-5-6)  – Best Liquid Fertilizer

Verdict: 4.5

Nutrient profile: 

• NPK ratio: 7-5-6
• Similar to the highly rated MSU formula, this fertilizer is also urea-free and has a complete nutritional profile.
• But the macronutrients are in different proportions: This fertilizer has equal NPK proportions (NPK: 7-5-6) and much less Calcium (2%) and Magnesium (0.5%).  
• The proportions of micronutrients are very similar to the MSU formula: Iron 0.1066%, Manganese 0.0525%, Zinc 0.0525%, Copper 0.0525%, Boron 0.021%, Molybdenum 0.011%.

Cost:  Following the manufacturer’s recommendation of dissolving 3/4 tsp of fertilizer in 1 gallon of water, the 8 oz (0.45 kg) liquid fertilizer that costs only $15.04 can make 63 gallons of liquid fertilizer.  And it costs only $0.24 per gallon of liquid fertilizer for feeding your orchids. 

1.6 “Grow More” (20-10-20)

Verdict: 4 stars

Nutrient profile:  

• NPK ratio: 20-10-20
• urea-free, a rather complete nutritional profile (same as Better Gro).  But, it lacks Calcium. In general, this is a good fertilizer, but not as good as the MSU formula.

Cost:  Makes 136 gallons of liquid fertilizer

Cost of fertilizer produced: $0.1/gallon

1.7 “Miracle-Gro” (30-10-10) – Budget Pick

Verdict: 3 stars

No products found.

Nutrient profile: NPK ratio: 30-10-10

Maybe due to its low price (less than $6 for 8oz in granular form), this is the most popular choice on Amazon.  But it is a rather poor choice for orchids because it is not urea-free.  30% of nitrogen is made up of mostly 27% urea nitrogen which needs to be decomposed by soil microorganisms first before it can be absorbed by the roots.  This means that only the remaining 3% is in nitrate form is available for immediate uptake.

Other micronutrients are: Boron 0.02%, Copper 0.07%, Iron 0.325%, Manganese 0.05%, Molybdenum 0.0005%, Zinc 0.07%.  But, like other non-MSU formula fertilizers, it has no Calcium and Magnesium. 

Cost: This fertilizer is very cheap.  Following the manufacturer’s recommendation of diluting 1/4 tsp of fertilizer per gallon of water, the 8-ounce bottle ($5.08) would make 192 gallons of liquid fertilizer.  It thus costs only $0.026 per gallon of fertilizer. 

1.8  “Espoma” liquid fertilizer (1-3-1)

Verdict: 4 stars

Nutritional profile:

NPK ratio: 1-3-1

Cost: Following the manufacturer’s recommendation of mixing 1/2 cap (2 tsp) of fertilizer per quart of water, the two 8 oz (256 g) bottles of liquid fertilizer which cost $24.99 can produce 24 gallons of liquid fertilizer and cost only $0.066 per gallon of liquid fertilizer for feeding your orchids. 

1.9“Miracle-Gro” (0.2-0.2-0.2) in spray bottle

16 oz

Verdict: 3 stars

This product contains an equal ratio of NPK, which is not nitrate-based. 

It does not contain other macro and micro-nutrients. 

The only upside of this product is that it is already diluted ready for use and it comes in a spray bottle which may be convenient for using it on orchids placed in the workplace.

This is the most popular fertilizer on Amazon based on the highest number of reviews. The reason, however, is mainly because it is bought to feed their indoor plants, outdoor gardens, etc. 

Ready-for-spray fertilizers are useful foliar feeding orchids but it should be done right by misting the undersides of the orchid leaves, rather than the crown.  And foliar feeding should be done in the evening or early morning when the stomata on the leaves are open for absorbing nutrients.

Nutrient profile: NPK ratio: 0.2-0.2-0.2.  It is very diluted to a concentration that is ready to be used directly on plants.  However, it is not urea-free, meaning that the nitrogen is not readily available for immediate uptake by orchids that are not grown in soil.  It also does not have Calcium, i.e. the same aforementioned issue with Miracle-Gro (granular).

It is unknown if the fertilizer has other macro and micronutrients as the ingredients are said to be patented.

Cost:  A pack of two 8 oz (or 0.125 gallons) spray bottles, which does not need to be diluted further, costs $7.84. In other words, it costs a whopping $62.72/gallon.  This is definitely too expensive for professional and amateur orchid growers. 

The only attraction is perhaps its convenience for people growing orchids at work that they have a bottle of fertilizer ready for use.

1.10  “Perfect Plants” Orchid Food (13-11-11)

slow-release fertilizer

Nutrient profile: This fertilizer only has nitrate nitrogen, potassium, and phosphorus in the ratio of 13-11-11.  There are no other macro and micro-nutrients.

Cost: Following the recommended dosage of 1/4  teaspoon of fertilizer pellets per 2-inch pot, the 5oz bag can last up to 3 years for feeding a single orchid.

2. Can I use an all-purpose garden fertilizer on my orchids?

You should use fertilizers specifically manufactured for feeding orchids, rather than an all-purpose garden fertilizer. 

This is because the nitrogen content in all-purpose fertilizers is mostly urea nitrogen, which requires the existence of a healthy population of microbes in the soil to break down the urea nitrogen into nitrates before it can be absorbed by the roots. 

Using “Jacks” 20-20-20 All-Purpose Fertilizer as an example, 17.9% of the 20% nitrogen is urea nitrogen, leaving only 2.1% in nitrate form for immediate uptake. 

“Jacks” also produces Liquid Orchid Food, with an NPK ratio of 7-5-6.  Of the 7% nitrogen, 5% is in nitrate form for immediate uptake.

3.  What is the best NPK ratio for orchids?

There are a variety of recommendations circulating among orchid growers regarding how to best feed their orchids.  The American Orchid Society recommends a 20-20-20 fertilizer (e.g. a formula adopted by “Miracle Grow”).  Better Grow (with 20-14-13) has also a large following.  But the most talked about is the “MSU formula” developed by Michigan State University. 

4. What is the MSU formula?

The Michigan State University (MSU) has developed three formulations that are suitable for well water (19-4-23), rainwater or Reverse Osmosis purified water or tap water (13-3-15) and K-Lite (12-1-1). 

The K-lite formula which is low in potassium and phosphorous is developed to mimic the nutrients plants receive in nature.  In general, the RO water formula is the preferred choice for home growers.

All the formulations are excellent for epiphytic orchids with a few common features. First, nitrogen is the most important macronutrient so a good orchid fertilizer must be high in nitrogen.  Also, it must be nitrate-based or urea-free meaning the nitrate-nitrogen can be absorbed immediately by the roots of epiphytic orchids.  Second, there is a high level of Calcium and Magnesium.  And finally, there are micronutrients to prevent deficiencies.

5.  Are slow-release fertilizers good for orchids?

It can work, but not for people who water their orchids by soaking and may not work well with chunky, less water-retentive inorganic media. 

If the temperature is too hot (above 85 Fahrenheit), the pellets may explode, releasing all the fertilizer all at once.

Related

Orchid Nutrient Deficiency: Symptoms & Solutions (Pictures)

Why You Should Foliar Feed Orchids (& How To Do It Right)