Make sure the water is damp as many of the flowers are hungry for water and in summer time the thirst is doubled.
Daisy which is commonly known as Black Eyed Susan, and has a bright yellow to orange petals with a deep brown to black center. This is a great flower to plant in the summer. It grows up to 3.5 ft tall and can also live over cool weather. Gloriosa daisy attracts butterflies, bees and even hummingbirds.
There are various factors like soil, water, fertilizers, etc. The best flowering plants for summer will be periwinkle, hibiscus, night blooming jasmine, daisy, aster, Grandiflora, dahlia, yarrow and many other.
Petunias are prolific bloomers, although some forms require deadheading to keep them going. However, most varieties will bloom throughout the summer, except in extreme heat.
Also, you can plant some decorative succulents in summer which gives a completely different look to your garden.
Jasminum (jasmine) is a popular climber with a delicate scent, and there are many cultivars for summer and winter. Jasminum officinale (summer jasmine) is perfect for a sunny, sheltered spot in mild regions of the UK.
The cheery yellow flowers of Jasminum nudiflorum (winter jasmine) will brighten up even partially shaded and cold sites at a time when little else is in flower.
Similarly, too much watering will void the soil from its important nutrients. so damp soil is good but doesn’t flood it.
Sunflowers say “summer” like no other plant. American natives, sunflowers are grow for beauty as well as harvested for seed.
An annual plant, sunflowers have big, daisylike flower faces of bright yellow petals (and occasionally red) and brown centers that ripen into heavy heads filled with seeds.