My wife and I have a worm compost pile in our workshop that processes a few pounds of food waste a week. Up until now, it has been used in outdoor gardens.

Now I am starting some indoor plant gardens and would like to use the nutrients to benefit them.

The problem is that the worm compost pile has various mites that don’t disturb things outdoors and are natural, but I don’t want those in my indoor gardening setup.

From what I’ve read, I can make compost tea, then throw out / recycle the compost remains and add that to my indoor gardening.

The other option that I’ve come up with is to do some sort of sterilization (baking) that I’ve seen some gardeners do when bringing outside soil indoors. Is that a dumb idea and would it remove all the nutrients that the worms worked to produce?

If I’m thinking about this all wrong, happy to hear any feedback and appreciate the help.

  • You can use worm compost if its produced correctly, so are you talking about a proper wormery set up, or just an open heap or pile of food waste in your workshop?
    – Bamboo
    Commented Jan 29, 2020 at 22:40
  • I would say it's a somewhat proper worm setup. It has the proper drainage, aeration and mix of brown and green compost material. I feed it a mixture of food waste like old greens, bread, vegetable cuttings, etc. No meat, oils or anything that would attract annoying pests. I supplement that with shredded cardboard tubes, paper for brown compost material.
    – opius_pie
    Commented Jan 29, 2020 at 22:42
  • Is it a closed system though - like in a proper wormery? See here gardeners.com/how-to/worm-composting/5714.html
    – Bamboo
    Commented Jan 29, 2020 at 23:47
  • Don't sterilize it!!! One of the best part of WC is the beneficial microbes that are living in it.
    – GardenGems
    Commented Jan 30, 2020 at 11:20
  • @Bamboo yes, it is a closed system and I follow all of those best practices. My worm bin contains small white mites that aren't harming the worms, but I am wary of bringing them into my houseplants.
    – opius_pie
    Commented Jan 30, 2020 at 15:49

1 Answer 1


Using compost or outside soil and bringing it in can be tricky. You want to maintain the beneficial bacteria and the properties of the organic matter that will help your plants. But you don't want to bring in lots of worms or other bugs.

The process I've learned and used to succeed with worm castings indoors is multiple steps/ideas:

  • Sift it thoroughly. First, you want to separate down to just the castings, pulling out worms and any bits that are not well processed. If you can see and pull out the worm cocoons then do separate those.
  • Let it sit for a bit. Keep it moistish and at a similar temperature to what it should normally be when it has worms in it, but let it sit still for a month or more. This will allow any bugs, worms, etc. to move out of their cocoons and out into the rest of the world instead of staying in the compost. It will also let any viable seeds sprout so you can pull those out. Keeping it moist and at a reasonable temperature will keep the beneficial bacteria alive.
  • Ammend your pots. Add in smallish amounts of the worm castings to your pots. Plants need soil mostly and just ~10% to 20% compost. You can do more or less and still get value, but that's a good ratio.

An alternative is indeed to make a compost tea and use that either as a foliar treatment (on the leaves) and also to water the plants. The solids that are left behind can be used outside in the garden while the tea can be used indoors without worrying about worms or other bugs coming in.

  • thank you, this is helpful and I will see what works for us!
    – opius_pie
    Commented Feb 10, 2020 at 15:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.