Potting Soil guide


For success in the Garden Tower system, good soil is critical. Using a quality organic “professional potting” soil or mix, meant for containers is essential. A good commercial organic potting soil (or “grower’s mix”) will optimize drainage, water retention, and aeration for both plants and the compost. We recommend you ask your nursery for a lightweight or fluffy grower’s mix or potting soil (organic is best but not required). Many “grower’s mixes” do contain some slow release fertilizer which will help your plants get going while your worms settle into their new environment. Some potting mixes may be completely free of fertilizers so please read the below Soil Amendment note.

Tip: Spend some time at a local Garden Center or talk to local gardeners not just about soils, but what types of plants will do well in your area or your situation (i.e. more\less shade, cool weather\high heat, for example)

Organic Soil Amendment – Fertilizer

If your potting mix does not contain any in-built fertilizer, we recommend giving the plants a boost in the beginning (until the compost column gets working) by using some organic soil amendment. As the central compost column begins to produce its own fertilizer, this will no longer be necessary.

Soil amendment can be commercially prepared or a DIY mix of organic nutrients from various natural origins. If purchasing a plant food to fortify your soil mix, mix with your soil to kick-start the movement of nutrients through the Tower.

Commercially prepared products should be:

  • An organic, non-manure-based plant food added to the soil makes nutrients immediately available in the system. OMRI Certified is best
  • Liquid organic plant food mixtures will provide the most available nutrition for young plants but have to be re-applied every so often
  • Granular types are more time-release and will provide nutrients for about three months
  • Make sure to purchase a naturally-derived plant food
  • We recommend staying away from animal manure products as they have an over abundance of salts
  • They should contain NO DPW (Dehydrated Poultry Waste), Municipal sludge (labled as Bio-Solids) or petro-chemically derived fertilizers (salts)
  • The application rate for a general purpose organic 4-4-4 is up to 1 cup / cu ft. soil