By seed starting mix I mean any seed starting medium, e.g. rock wool, peat moss, coco coir, etc.
In January, YouTube creator Soil and Margaritas / Garden Life published a video of her latest experiment around potting mixes (that’s right, potting mixes) for starting seeds indoors.
Her rationale for starting her seeds in potting mix is when she uses seed starting mix, she eventually transplants them to potting mix anyway. She acknowledges that not all potting mix is suitable for starting seeds - for example, one of the specific products she tested was very chunky, which significantly hindered those seeds’ germination and growth. That said, she claims that some potting mixes are “fluffy” enough to work well enough for starting seeds.
She tests Chinese noodle beans, sunflowers, and zinnias w/ six products:
- Vermont Compost Company Feed the Soil Fort Vee All Purpose Compost Based Potting Mix (the one she used in 2025)
- Miracle Gro Potting Mix
- Promix Premium Moisture Potting Mix
- Fox Farm Ocean Forest Potting Soil
- Black Gold Natural & Organic Potting Mix Plus Fertilizer
- Espoma Organic Potting Mix
Not accounting for price, personally I’d rank the performance as follows:
- Vermont Compost Company Feed the Soil Fort Vee All Purpose Compost Based Potting Mix (the one she used in 2025)
- Miracle Gro Potting Mix
- Fox Farm Ocean Forest Potting Soil
- Promix Premium Moisture Potting Mix
- Black Gold Natural & Organic Potting Mix Plus Fertilizer
- Espoma Organic Potting Mix (performed the worst, although she acknowledges in her video that this particular product is very chunky and this company has a seed starting mix on the market)
What do people of c/gardening use for starting their seeds? What are your thoughts on this test?
To my understanding, high nutrient soils can burn baby seedlings. This is especially true for blends of peat moss with artificial fertiliser but also uncomposted/poorly composted manures.
I usually go for last years, ie depleted, soil. For small seeds i just pulverise it with my hands for the top centimeter. This year I used soil made of composted manure mixed with sand/fine gravel, crushed terracotta, charcoal and woodpulp i took from some decomposing tree in the forest.
Tomatoes, kale, cauliflower, oregano, sunflower, paprika and chili all took off no problem. No signs of life from my cucumbers and artichoke, tho I think at least the cucumber got eaten by mycelium that spread from the composted manure.