How to Fertilize Indoor Plants | A Beginner's Guide!

Jul 13, 2020

You may have heard that you need to fertilize your indoor plants, but if you're new to houseplants you may not know when, why and how to do it.   Never fear, fertilizing your houseplants can be simple...here's what you need to know.

Why Fertilize?

Houseplants need to be fertilized in order to be healthy and look their best.  In nature, plants are exposed to the nutrients they need to thrive.  Your houseplants are cut off from the outside world, so they don't have access to all of the minerals and vitamins that can be found in nature in the form of decaying plant material, and other natural elements.  Your indoor plants depend on you to provide these nutrients for them!  Watering your plants will wash away nutrients from the soil over time, so it is up to you to replenish the essential minerals they need to grow lush and healthy!

When to Fertilize

Fertilizing is a great way to maintain the health of a plant.  So the right time to fertilize is when you have a lush, healthy plant and you want to keep it that way. Traditionally, the rule is to fertilize in the spring and summer and back off fertilizing in the winter.  It really depends on the type of plant and the conditions your home provides. Tropical houseplants can grow year-round with the right conditions, so if your tropical plants are still growing then you may want to keep fertilizing.

Types of Fertilizers

There is a wide selection of houseplant fertilizers available.  Some indoor plants respond better to specific types of fertilizers.  If you want a general fertilizer that will work well for most houseplants, then consider using a complete liquid fertilizer (an equal solution of nitrogen, phosphorus, and potassium).  This is a great way to ensure all of your plants receive an added boost of nutrition.  Make sure to read the instruction labels and look for brands that includes micro-nutrients needed by all indoor plants!

When using a complete liquid fertilizer just remember to dilute the fertilizer first. Using just a straight fertilizer can potentially damage the roots and leaves of a plant, so diluting to the recommended strength helps protect your plant.  You may want to dilute it more than the manufacturer recommends if you find yourself feeding your plants more often.
Indoor plant fertilizers fall into two categories: organic and chemical.  Here are examples of both organic and chemical plant fertilizers.

Organic Fertilizers

  • Worm castings
  • Kelp
  • Fish emulsion
  • Compost tea
  • Plant extracts
  • Bat guano
  • Eggshells
  • Aquarium water

Chemical Fertilizers

  • Complete balanced liquid
  • Slow-release
  • fertilizer stakes
  • Use a higher ratio of nitrogen for foliage plants

Fertilize When You Repot Your Indoor Plants

Another way to ensure your houseplants get the nutrients they need is to amend the soil when you repot your plants. Including a sterile compost or worm castings in the potting soil can help your plants thrive.  If you amend the soil then just remember to further dilute any liquid fertilizer you use.

If you want to maintain lush greenery, promote new leaves, and see just how long you can get your vining plants to spread out, then fertilizing your houseplants is the way you make that happen.  Find out more about how to fertilize indoor plants.