You can just seed the sunflower seeds directly in the ground and cover them with floating row cover. This has worked well for me to keep bugs, birds, rabbits, and deer from eating many of my sunflowers. The row cover can be left on until the plants get nearly a foot tall. At that point deer will still eat the leaves, but they seem to be safe from smaller critters. Something will occasionally get under the row cover and do some damage, but most of my plants make it.

ThinMan

Mine were eaten last year by deer. I put a fishing line fence around them to no avail.

This year they are inside the fenced vegetable garden and are growing strong - in fact providing shade where shade is not wanted. I am growing the Mammoth kind - 8 feet is the max height.

Interesting plants.

Mine are actually growing awesome. I am very new to this and just sprinkled some seeds in a patch if soil back in April. Sunflowers have actually been the easiest for me!! Little maintenance.