Any suggestions or experiences?
Vermiculite is not a fertilizer, so cannot fertilize any seed. It is used in some seed planting mixes, but does not contain nutrients for plant growth.
Vermiculite is best for small fine seeds but yes it can be used for any seed but i wouldn't use it for say a sweetpea sized seed. I would stick to using it for small seeds (any) and seed compost for the bigger ones.
No, vermiculite does not contain any nutrients. You will have to add fertilizer to it. Use seedling potting soil that contains fertilizer. High quality seedling mix contains agents that make it easier to absorb water and components that retains moisture.
Vermiculite is not a fertilizer; it is a mineral that is added to improve a soils ability to handle fertilizers. It helps with root growth, soil structure, oxygen, and other factors that many plants desire. If you're growing seeds, the addition of vermiculite surely would help, but again it is not a fertilizer.
