In this newsletter, I discuss earthworms in container gardens; risks and safety tips for using bagged soil mixes; introduce a new herb and medicinal plant guide; share tips for changing seasons and moon gardening timing. Grab a cuppa and dig in!
Earthworms in Pots
Earthworms provide incredible benefits in the garden. They help aerate the soil with their tunnels, opening soil pores and improving soil structure and drainage. This helps plant roots access oxygen and allows moisture and nutrients to penetrate. They digest organic matter and leave their castings (‘vermicast’ or poop) with soluble nutrients plants can access immediately, improving crop yields. Vermicast is humus and a pure plant food and soil conditioner. Earthworms are wonderful soil workers indeed!
If you have container gardens and add garden soil or compost to your potting mix, then you may sometimes find an earthworm or two. Whilst earthworms perform many valuable roles, they can occasionally be problematic in pots, especially small ones. If you have just one or two worms, it may take a while for their tunnels to make an impact. However, if you have a community (yes they will breed!) then the plant roots may become exposed to too much air in the potting mix.
The other thing to watch for is if you are raising seedlings in a small pot and there is little organic matter in the potting or seed raising mix, any earthworms present may resort to eating the plant roots if all the organic materials are consumed. I was doing container garden maintenance once and picked up an old pot that was very heavy. Curious, I discovered it was almost pure worm castings that were retaining moisture and the pot was filled with earthworms! They had turned all the potting mix media and mulch into vermicast.
Feeding Earthworms and Repotting Plants
If you notice fresh worm castings on top of the potting mix or mulch, or around the base of the pot, these are a clue of their presence. If you notice a potted plant declining and suspect you have earthworms in your potting mix, you have a couple of options. Keep providing plenty of alternate organic matter like mulch to the top of the pot for the worms to eat instead of your plant roots.
Alternatively, repot your plant. This is simply a matter of upturning your pot and gently setting aside your plants in a cool location. Give them a quick soak in liquid seaweed as a boost. Then look for a network of tunnels in the potting mix and worms squirming around. If you can, rescue your earthworms and add them back into your garden soil where they can continue to work for you. The worm castings are indeed beneficial, so you want to retain this valuable free plant food in your potting mix.
Get your own easy DIY Homemade Potting Mix Recipe Guide using worm castings.
Learn more about the business and biology of worms with the Worm Farming Secrets eBook.