Late-Summer Flowers | Gardener's Supply (2024)

FAQs

What is a late summer flower? ›

Annuals ensure color throughout the season

There are some perennials that pop up briefly in late summer: think coneflower, asters, Helenium, cimicifuga, sedum, rudbeckia, and phlox.

Short-day plants form flowers only when day length is less than about 12 hours. Many spring- and fall-flowering plants are short-day plants, including chrysanthemums, poinsettias and Christmas cactus.

While spring may be the most common season to tend to your flower garden, that doesn't mean you can't grow something beautiful this fall! August is often the perfect time to start planting because it encourages root growth in the soil before things start freezing, giving your garden a head start for the spring.

Those that don't require deadheading should be left alone except for watering them when the soil is dry. You don't need to fertilize annuals after the end of August. Plants that flower better when deadheaded, such as marigolds, Salvia and Zinnias should have their spent flowers clipped off.

For this Blooming Period, we're highlighting some late summer/fall favorites: callas; China asters; lisianthus; perennial sunflowers; and zinnias.

Daylilies are popular, easy-to-grow, low-maintenance perennials that are tough, long-lived, and tolerant of neglect. They bloom profusely, though individual blooms only last a single day and varieties number in the tens of thousands. Daylilies grow from fleshy roots, unlike true lilies that grow from bulbs.

It may sound like something out of a fairy tale, but it's real! This is the Agave americana, also known as the century plant. It was once thought to bloom every 100 years but has since been proven to only live up to 30.

Annuals. Annuals take a single year to complete a full life cycle. Most are planted in the spring, bloom in the summer, and die in the fall. A few, known as winter annuals, germinate in the later summer and autumn, are dormant during the winter, and grow during the next spring and summer.

Most plants grow best in temperatures ranging from 59°–86°F. When temperatures above 90°F are sustained for long periods, plant growth is slowed, and some plants begin to show signs of stress.

Can you plant flowers in September? ›

It's time for planting fall color, such as mums and asters, as well as sprucing up planter boxes. You also may be surprised to learn that it's the best time of year to plant perennials and shrubs (trees, too!) while plants still have an opportunity to establish their root systems before the ground freezes.

Unlike perennials, annuals do not come back from season to season so there is no reason to leave these in the ground. Pull them up, roots and all, and add them to your compost pile. Remove weeds and leaf debris. These are common places for diseases and pests over winter.

Another good idea is to remove annual flowers after a killing frost. In addition, perennials that show signs of disease should be cut back in the fall.

Designing with late bloomers:

Long-season annuals, such as marigolds, cosmos, salvias and scaevola, provide colorful companions. Consider growing the bulbs and the gentian in containers for temporary, portable color.

Hardy geranium.

Also called cranesbill, this perennial has an unusually long flowering period — all summer until fall. (USDA Zones 5 to 7.) Start with one-gallon plants, choosing plants with plenty of healthy, lush foliage and avoiding those that have already started blooming.

Late-flower describes a time when cannabis plants have completed their most vigorous bout of blooming.

Late Summer begins around the third week of August and runs through the Fall Equinox. In August, Nature is undergoing its last burst of growth before harvest time. The energy of this season corresponds to the nurturing Earth element.