Best Houseplant Fertilizers for Foliage & Flowers

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Best Fertilizer for Indoor Houseplants
Jack’s Classic formula is my pick for best all-purpose houseplant fertilizer.

Fertilizer is such an important part of growing houseplants. Your plants need nutrients and if you want them to look their best, they’ll need to be fed several times a year (some more than others).

It may be tempting to just grab a cheap bottle of Miracle Grow – which is better than nothing. But I’ve found far better solutions on the market at reasonable prices. Depending on the type of houseplant you’re feeding, here are my top picks for the best fertilizers.

My Picks for Best Houseplant Fertilizers

Why I Love Jack’s Classic 20-20-20 All Purpose Fertilizer

The Jack’s brand of fertilizer was recommended to me by my local nursery several years ago. Before then, I was using Miracle Grow – as most people do. Once I switched, I could never go back. I noticed a huge difference in both leaf and flower quality when feeding my plants with Jack’s.

I’ve been using Jack’s for years and can’t recommend it enough. Here are some of the many reasons I love this fertilizer:

  • Promotes Foliage Growth – This plant food feeds through both the roots and leaves, which promotes rapid leaf growth. And trust me, you’ll be able to see the difference as soon as you start using it. In addition, it helps keep your foliage beautifully green and healthy.
  • Water Soluble – It can be difficult to find a high quality, water-soluble fertilizer with this ratio of nutrients (completely balanced 20-20-20). It comes as a powder that you mix with water and apply directly to the soil. Your plants take the food up through their roots and into their leaves.
  • Truly AllPurpose – If you can only afford a single fertilizer, this is the one to get. The all-purpose formula can be used on all indoor plants, from delicate orchids to hardy cacti. If you aren’t sure which type of fertilizer to use on your specific houseplant, this one will nearly always do the trick.
Jacks Classic Houseplant Fertilizer
Jack’s Classic is water soluble and easy to measure.

Why I Love Jack’s Classic 15-30-15 Houseplant Special Fertilizer

In case you haven’t noticed, I am a big fan of Jack’s products. I use the All-Purpose for my foliage plants and the Houseplant Special for my flowering plants. one of these formulas could be used exclusively on all plants, but I’ve found this combination works best for an indoor garden.

Here are the reasons I love the Houseplant Special formula:

  • Higher Phosphorus Content – Flowering houseplants need a higher phosphorus content to produce the best blooms. While an all-purpose plant food will work for your bloomers, I find that a 15-30-15 formula produces the biggest, most beautiful flowers.
  • Reasonably Priced – As with all of Jack’s fertilizers, you get a lot of bang for your buck. While they aren’t as cheap as Miracle Grow, they are still very reasonably priced. Plus, a container lasts a LONG time and you can buy in bulk online. Check the current price on Amazon for yourself.
  • Won’t Burn Your Plants – This formula has a high safety factor and won’t burn your plants – as long as you use it according to the instructions. It includes a little spoon for measuring so it’s basically impossible to use too much and harm your plants.

What to Look for in a Houseplant Fertilizer

If you want to keep things simple, look for a good quality all-purpose fertilizer and use it on all your houseplants. If you want the best possible flowers on your blooming plants, look for a high phosphorus formula such as 15-30-15.

In fertilizers, you’ll see they have a series of numbers in the description, such as 20-20-20 or 15-30-15. These numbers tell you how much nitrogen, phosphorus, and potassium the formula has. The first number indicates nitrogen, the second number is phosphorus, and the third number is potassium.

For plants that require a high phosphorus fertilizer, the second number should be larger than the first and third. A 20-20-20 blend is completely balanced and suitable for almost all plants. If you aren’t sure where to start, get a balanced blend for foliage plants and a higher phosphorus blend for flowering plants.

You will never go wrong with this combination.

Don’t forget to read the individual care guides for your specific houseplants to see if they have any special nutrient needs. Anthurium plants, for example, thrive with a high-phosphorus blend like Jack’s Houseplant Special. While most ferns perform best with an all-purpose fertilizer like Jack’s Classic.