First, a reminder of some points from the Garden Agreement.
Your Garden Plot – Environment
We are an organic garden. Herbicides, insecticides and other pesticides or chemical fertilizers (including other amendments such as lime, peat moss or topsoil/potting soil) cannot be used anywhere unless they meet the Canadian Organic Standards. If in doubt, contact a member of the Abbotsford Community Garden Society Board.
- Feed the soil, not the plants.
- Add organic matter. This can be compost, animal or mushroom manure.
- Dig the organic matter into the top layer of soil.
- To help combat weeds, you can mulch between rows. Organic mulches are best. When they breakdown, they benefit the soil.
- Mulching also helps to conserve moisture and modify soil temperature
- Mulches should be applied when soil is moist.
Organic gardening methods only
- Organic methods (acceptable under the Canadian Organic Standards) are required.
- Any chemical control products, including herbicides or chemical fertilizers cannot be used unless approved
Soil Amendments Provided by the Abbotsford Community Garden
From time to time, the Abbotsford Community Garden (ACG) Board arranges for soil amendments to be deliver to the garden. In the past couple of years this has been either Net Zero Waste Compost (NZC) or spent mushroom growing media (SMG).
As a plot holder you are not obliged to use either of these products. ACG makes it available to those who wish to use it. You are free to bring your own amendments to the garden (following the requirements in the garden agreement) or not use amendments. Any materials added to your garden must meet the Canadian Organic Standards (if not to the letter at least in spirit).
Based on a soil test done a couple of years ago, most garden plots have more than enough nutrients. Imbalances in various nutrient levels may be present, so alternating the use of NZC, SMG or any other organic amendment is a good idea.
Nitrogen deficiency may appear early in the year but with the level of organic matter in the soils, it will become available as the soils warm unless there is an excess of carbon rich or undecomposed matter like peat, wood chips or straw. In this case, soil organisms will use the available nitrogen to consume the carbon rich matter at the expense of allowing plant roots to take it up.
Comparing Net Zero Waste Compost and Spent Mushroom Growing Media
Net Zero Waste Compost
- produced from green waste (lawn and garden vegetation and kitchen scraps) which is composted and screened
- comes with a small amount of foreign matter (like stones or fruit labels) which is allowed under regulation
- usually fully composted and does not reheat
Spent Mushroom Growing Media
- produced mainly from chicken manure, straw, gypsum, and water
- often not well decomposed or fully composted and may contain organisms (bacteria) that make it reheat
- can also contain foreign matter (twine, plastic)
|Product||pH||Salinity||Total Organic Matter||Carbon Nitrogen ratio||Total Nitrogen||Phosphate P2O5||Potash K2O||Calcium||Magnesium||Sodium|
|Net Zero Waste Boost – Fine Screened (1/4”) – A||6.9||6.9||56.9||12||2.50||0.94||1.20||2.40||0.40||0.21|
|Spent Mushroom Growing Media – B||6.6||13.3||26||14 to 17||1.0 to 1.9||0.5 to 1.6||1.2 – 2.9||2.3 to 8||0.4||0.6|
B various sources – highly variable depending on producer of media and handling after mushroom growing is completed
If you still have questions, we suggest you email the garden administration email where if time/expertise is available they will be answered. Alternatively, you could speak to a Master Gardener at Van Dusen or UBC Botanical Gardens.