My seeds didn't sprout?
Not all seeds germinate. One way of testing the viability of your seeds is to wet kitchen paper and place it in a ziplock bag along with your seeds. Place the bag in a sunny window. The seeds should sprout within a few days. If they don't they are not viable seeds and it's not worth planting them out. Try again with more seeds.
Something's eating my sunflowers!
Gardens pests such as slugs, groundhogs and rabbits love sunflowers as much as we do.
Remedies include sprinkling organic, non-toxic slug pellets in your garden bed and planting chives throughout your sunflower bed. Critters do not like the scent of chives and other herbs such as garlic and oregano.
If you have a handle on the identity of the particular pest plaguing your sunflowers, research remedies online.
My Sunflowers look wilty
Water them! Sunflowers are thirsty plants. If you live in an area with little or intermittent rainfall, water your sunflower bed to prevent the earth drying out and wilting your sunflowers.
Taller sunflowers need full sun in a protected area of the garden. Planting en masse (lots of them) close together (6" or 30cm apart) helps with resistance to some wind. The tallest require more help such as staking or securing to fences or walls.