Zinnias win the butterfly popularity contest during those hot summer days. They are like a butterfly magnet to the garden and will stop walkers in their tracks.

While I'm not a "Zinnia Guru" I have learned a few tricks which seem to work for me.

#1. Buy a variety you like and seems to work well in your climate. 

My favorites are: Exquisite Pink from Lake Valley Seed. (available in many nurseries), and "Benary Giant - Zen on a Stem" from Redbud Farms

For the smaller butterflies, I like the "Dwarf Classic Mix" from Lake Valley Seed.

#2. Don't try to transplant Zinnias.

Plant the seed directly in the garden, in early summer when it's starting to get hot.

I've tried many times to start my own Zinnias from seed and transplant them to the garden. They never do well and my germination rates are terrible. I now wait until it starts to get hot. For the St. Louis area, mid-June is a good time to plant the seed.

3. Buy varieites which are mildew resistant.

Some Zinnias are more resistant to mildew than others. While some gardeners recommend watering from the bottom with a soaker hose, for me that's too much work. If a plant doesn't do well with my standard sprinkler, it gets pitched. My varieties seem to be very mildew resistant.

4. Deadhead the flowers during the season.

5. Cover and water.

I work my seeds into the top 1/2" of soil and then sprinkle them with a light covering of potting mix. Keep the area moist until the seeds sprout. (less than a week)