Why Use Homemade Seed Starting Mixes?
Starting your own garden transplants from seed is smart because it gets you a big-time boost in harvesting vegetables from the garden. Plus, you can grow and try whatever variety you want rather than depending on varieties that the garden center might have. But, if you’re using prepackaged bags of seed starting mix from the store, it can get expensive quick.
The good news is, it’s easy to make your own homemade seed starting soil mixes with just a few ingredients from the garden center. We’ve been using both recipes below for making “soil blocks” to germinate seeds and grow transplants (see Use Soil Blocks for Super Healthy Seedlings), and find that these recipes germinate seeds as well or better than the mixes we used to get from the store.
tomato seedlings in soil blocks
Although we use both recipes for soil blocks (the first for 2″ and larger soil blocks and the second for 3/4″ soil blocks), the first recipe also works well for starting transplants in containers. Both recipes are from The New Organic Grower by Elliot Colem
Soil Mix for 2" Soil Blocks or Transplants
Ingredients
- 3 buckets (10 quart bucket) brown peat
- 1/2 cup lime
- 2 buckets coarse sand
- 1 cup blood meal
- 1 cup colloidal phosphate (22%)
- 1 cup greensand
- 1 bucket soil
- 2 buckets compost
Notes
For the very smallest “soil blocks” (3/4″ soil blocks) a different recipe is used that isn’t as rich.
Soil Mix for 3/4" Blocks
Ingredients
- 4 gallons peat
- 1 cup colloidal phosphate
- 1 cup greensand
- 1 gallon compost
Instructions
- Mix all ingredients together similar to the recipe above.
Wayne Larson says
I love using soil blocks, but I have experienced quite a bit of damping off. Do you have any suggestions for preventing damping of using the 2” mix? I do bottom water and water sparingly.