I want to cultivate portobello mushrooms anyone know be to find the core?

New gardenia and turning leaves?
Answers:    One great place to purchase mushroom spores and books on them is a company called Fungi Perfecti. They have a catalog and indoor and outdoor mushroom kit. Their website is www.fungi.com or do a search for the company name.
Can plants grow short soil?
Mushrooms don't grow from seed. They are a fungus, and originate from spores.

You can buy spore-inoculated log "kits" for mushroom growing online.