Using Coconut Coir For Seed Starting Medium

Ashley
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Coconut Peat Seed Starting

Are you on the fence about using coconut coir for seed starting? Or maybe you are wondering what else needs to be added into a coconut coir seed starting mix. This Gardening In Canada article is going to look at using coconut coir as a seed starting medium.

If you are new to this blog my name is Ashley and I am a soil scientist. I am located in a Canadian Zone 3 and a USDA Zone 4. I write articles, make YouTube videos, Instagram & Facebook posts all designed for Canadians and Cold Climate gardeners using science-based methods. If you are looking for anything specific be sure to let me know in the comments down below.

Why Should You Use Coconut Peat For Seed Starting

One of the reasons people opt to use coconut coir is availability. In certain areas of the world, peat moss is difficult and expensive to obtain. If you are an environmentally conscious person it is likely you are concerned about the long-term use of peat. But ultimately coconut coir is the only substitute for peat starter due to its sterile nature.

If the manufacturer has stored the product correctly it is also unlikely you will have any fungus gnats or issues with damping off. For more information on how I sterilized my seed starting mixture check out the video below. 

What Should You Add To A Coconut Coir Seed Starting Mix?

Absolutely nothing. I know this sounds really odd but seedlings do not need much nutrients-wise and despise any sort of air infiltration. If skip the perlite and back my cells full of coir or peat. I avoid the addition of composts, manures, vermicomposts, etc. There are a few reasons for this the most obvious being it is not sterile and therefore may have harmful fungi and bacteria.

This addition may result in dampening off and poor germination. The second reason for not using composts in your seed starting mix may be less well known. And it is the concept of allelopathy in composts that arent “old enough”. This happens when certain plant materials suppress the germination of seeds. This concept is well understood in the science community and is a natural phenomenon. It is the plant’s ability to reduce potential competition in nature but ultimately can harm your seedling germination rates.

What you can add however are nematodes. These will help fight fungus gnats and any other bug issues that may arise over time. For more on this check out my article on beneficial nematodes.

Things To Note When Using Coconut Peat Seed Starting Mixes

The type of coco coir is key and you want to get the stuff labelled peat. I find coco coir to be almost chunky and stringy in nature which will result in too much airflow. Coco peat will be sifted and also finer grain which is exactly what you want.

Water retention in coconut coir tends to be lower in my experience. This means more watering may be needed. If you are new to using coco coir for seed starting be sure to check back regularly. If needed fill up the bottom reservoir and allow capillary action to do the heavy lifting. 

Are you on the fence about using coconut coir for seed starting? Or maybe you are wondering what else needs to be added into a coconut coir seed starting mix. This Gardening In Canada article is going to look at using coconut coir as a seed starting medium.

Using coconut coir for seed starting
Using coconut coir for seed starting