Finished compost is a valuable source of fertilizer and an excellent amendment for flowerbeds and vegetable gardens. Incorporating compost improves soil structure: it loosens heavy soils and provides body to light soils. Compost also adds nutrients and will enhance the growth of all your plants.

When is your compost ready to use?

Ripe compost should look like good, rich soil. The decomposition process takes a minimum of three months, with a lot of work, and up to three years, depending on the compost materials you start with.

Compost is ripe when it has a:

  • Brown or black colour
  • Earthy smell
  • Crumbly appearance
  • Light and homogenous texture

Between 3 and 6 months

Use as mulch around trees. Compost at this stage contains partially decomposed materials and should not be incorporated directly into the soil.

Between 7 and 9 months

This is mulching which you should spread on the soil in flowerbeds and vegetable gardens in the fall. It will continue to mature during the winter and will enrich the soil in spring.

More than 10 months

When it is ripe, or fully mature, compost is the perfect organic amendment for planters and flowerbeds, the vegetable garden, lawn, and generally all plants. It improves soil structure. Prepare the earth by mixing compost into the soil to ensure healthy plant growth.

Where should compost be applied?

Fruit trees, trees, shrubs, and rose bushes

  • Annual maintenance – spread a layer approximately 3-5 cm deep at the base of trees and plants.
  • Planting – mix compost into the soil, maintaining a 20% ratio.

Vegetable garden

  • Throughout the season – spread a 1 to 3 cm layer around the base of plants according to the plants’ needs:

Demanding plants (2-3 cm)

Moderately demanding plants (1 to 2 cm)

Less demanding plants (less than 1 cm)

Celery, cucumbers, squash, eggplants, potatoes, tomatoes, cabbage, corn

Lettuce, spinach, carrots, asparagus, beats, green beans, parsley

Herbs, onions, shallots and garlic, radishes, turnips, beans, strawberry plants

  • In the spring – spread approximately 2 cm between rows.
  • Planting – mix compost into the soil, maintaining a 50% ratio.

Groupings, borders and flowerbeds

  • In the spring – incorporate a layer of approximately 2 cm into the soil
  • In the fall – spread a layer of approximately 2 cm over the surface
  • Planting – mix compost into the soil, maintaining a 25% ratio.

Planters and potted plants

  • Old plants – replace 2 cm of the soil on the surface with new, mature compost.
  • New planting – mix approximately 30% of mature compost into the soil.


  • Planting from seed – mix 8 to 10 kg/m2 of compost to a depth of 10 to 15 cm.
  • As topdressing in the spring – spread 1 to 2 kg/m2 of compost on the surface of the lawn (ideally after aerating the soil).