I just put together my first batch of soil from a members blog. While sourcing the amendments I learned about the 2 aeration mediums. Any thoughts?
Vermiculite has better water retaining properties, if you're looking strictly for aeration, go with perlite. It has a medium water retention rating while vermiculite had a high rating. I remember going half on a dime sack
Perlite in soil mixes greatly improves aeration and slightly alters the soils substructure, keeping it loose and allowing for good drainage and oxygen content. Vermiculite in soil mixes gives a very light open soil which will hold more water, increasing the times between watering. Vermiculite also has excellent ion exchange properties which absorb excess nutrients and release them slowly to the plants via the finest root hairs and Mycorrhizal funghi. A combination of the two mediums works well at a 2:1 ratio in a soil mixture. 2 Parts Perlite : 1 Part Vermiculite.
I agree Use both. There's both plus sand, lava rocks, rice hulls and grow stones for aeriation in my soil. I couldn't tell you the ratios. Its all been added at different times in-between grows.