DIY: How to build your own in-ground worm bin

An in-ground worm bin is an alternative to multi-layer worm bins that sit above ground level. Though an in-ground bin can be made from various materials, a simple and cost-effective bin can be made with a 5-gallon bucket; we’ll share how in this tutorial in a few simple steps!

In-ground worm bins have a number of benefits. This is the vermicomposting option we recommend most for folks who live in inland areas where temperature fluctuations are greatest. The soil around the bucket provides insulation and a refuge that worms can escape to when temperatures outside temperatures fluctuate. As the worms move through the soil, they will help aerate the soil and leave behind nutrient-rich castings, all to the benefit of your plants. And don’t worry– the worms won’t go after your plant roots — they only want your food waste!

Materials:

  • 5 gallon bucket
  • 5 gallon bucket screw top lid
  • Motorized drill
  • ½”-¾” paddle (spade) bit
  • Shovel

Directions:

  1. Secure screw top lid on to the bucket.
  2. Drill about 20- ½” or ¾” holes around the side and 10-¾” holes around the bottom, evenly spaced apart.
  3. Dig a hole about 13” deep and 11″ wide to fit and bury the bucket. The screw top should remain above surface level.
  4. Remove or bury bucket handle.

After making the holes in your container, we recommend that the bucket be sunk in an area with fairly soft and moist soil. If your soil is high in clay, then you need to make sure the bucket can drain. Place damp bedding (shredded paper, coconut coir, etc.) and red wiggler worms into the sunken container, and you can begin adding in your food waste! Just as with any worm bin, be sure to always cover fresh food waste with a layer of bedding to reduce insects and other pests. Folks often start with 4-6” of bedding, bury in their food waste, then add another 4-6” layer of bedding every couple weeks. Note that if you go this route, the layer on the bottom will finish being composted first, and you will have to remove the top layers to harvest the castings from the bottom. 

Have a question about composting? Give us a call at (760) 436-7986 ex. 700 or email compost@solanacenter.org.