So, I picked up a pouch of sunflowers seeds at my local Giant, (they said organic so i splurged and got them). When I got home, I looked at the pouch and saw a little 12 in the corner, and I was quick to jump to conclusions and thought it was 12 INCHES. Little did I know, it meant 12 feet, and after taking a second look, I realized they were Mammoth Sunflowers! I've planted them back around maybe early March, or late May? Only one survived (the rest fell victim to rabbits :( ) now it's planted, it already has its already growing it's 4th set of leaves. I have it in a milk jug cut in half, but I'd like to know how when to transplant it!
Certified GKH Gardening Expert
You can plant out your seedling, make sure you harden off the plant for a few days.
These links will help you.