containers

Unusual plants. Maybe Desert plants, growing in sand ?
Aloe Vera etc. creating an interest for people to enjoy,
learning new names, plant families etc.

When I think of July, my first thought is Cannas. Many of them are glorious and the foliage is as nice as the flowers. They would look nice augmented with lavender, catmint & or freesias.

It depends on the size of the planter. Rather than use flowers, you could plant one with foliage colour - several heucheras for example with a variegated carex in the centre.

Fuchsias can look brilliant