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Starting tomatoes from seed #780647
Asked January 22, 2022, 8:09 PM EST
Washtenaw County Michigan
Expert Response
Paul, thanks for the question.
There are many formulas for seeding mixes. It seems that the ratios for creating a seed mix vary considerably. Most commercial mixes are primarily soilless mixes and pasteurized to help prevent diseases like damping off. You may need to adjust the formula to drain better by adding less worm compost/compost or adding more worm compost and vermiculite if you need more moisture retention. Starting mixes tend to be finer and lighter than potting mixes. A 4:1:1:1 of coir to vermiculite to perlite to worm castings is frequently suggested. Check the following links for an idea of what ratios should work.
- https://www.canr.msu.edu/news/potting_soils_and_seed_starting_mixes_for_your_garden
- https://today.oregonstate.edu/news/set-seeds-right-path-homemade-planting-medium
I hope this is helpful.