Container mixes and compost use

container mixes

Compost can be a dynamic addition to container mixes, naturally boosting plant performance while reducing watering requirements.

Compost use in container mixes can also reduce the need for fertilizers and suppress disease.  It lightens the soil to allow more water and air to circulate through the root zone.

McGill SoilBuilder compost can be considered self-pasteurized due to the heat generated during the composting process, yet it preserves and delivers the beneficial microbial populations required for healthy soil functions.

Container mixes: compost use instructions

McGill recommends its SoilBuilder compost for container mixes.  SoilBuilder is an STA-certified, premium quality compost.  Its performance attributes make it ideal for custom blending.

Blend ratios

If accustomed to using yard waste composts, please know the addition of professional-grade SoilBuilder may provide a richer blend.   While some plants (like tomatoes) may do well in an all-compost container, we recommend no more than 25 percent compost in a container mix.

When using compost as a part of a mix, it is important to ensure all ingredients are well-blended.  The blend should be homogeneous (even distribution of all ingredients) with a uniform particle size — no clumps.

Compost vs. peat moss.

SoilBuilder can be substituted 1:1 for peat moss.

Container mixes and watering requirements

Compost will hold more water than some container mix components.  For those new to compost-amended mixes, it’s easy to over-water.

Do not use automatic watering systems until you can determine and adjust watering schedules to meet the needs of your compost-amended potting soil and the plants it supports.