I am growing giant zinnia from seed and transplanting them to the garden. They now have their first true leaves and are about three inches tall. They look quite spindly. This may be because they are supposed to finish out at thirty inches tall. Anyhow...is it proper to plant these at the existing ground line with three inches above ground, or would it be better to bury the plants so that the leaves are just above ground (like planting a tomato). Any thoughts wold be appreciated.
TIA EJ in NJ