Dahlias are excellent additions to East End flower gardens, in the ground or in containers. The plants bloom nonstop all summer until frost shuts them down; they reach their peak in many gardens in August and September. There’s a range of warm colors available from pastels to brights: shades of red, rose, pink, yellow, orange, and white, and a variety of flower forms — from full, round pompoms to single and daisylike to slender petaled and spidery. The flowers come in many sizes, too, although the big dinner-plate types are hard to mix with other plants in the garden. Plants range in size from foot-high dwarfs to 3- and 4-footers. Use dwarf dahlias in the front of the garden beds and borders or in pots. Taller varieties can go into the middle ground of a sunny bed or border, or you can combine them with other annuals in large containers. Dahlias combine well with daisy-like flowers such as coreopsis, spiky blossoms like salvia and veronica, small-flowered baby’s breath, and many other flowers.
Dahlias are not true annuals; they grow from tuberous roots that are tender. But you can dig them up in fall and store them indoors over winter to replant in spring. The plants grow best in soil that’s fertile and moist but well drained. Amend the soil with compost in the fall for planting the following spring. Good drainage is important; dahlias will rot in soggy soil.
Local nurseries and garden centers sell blooming-size dahlias for summer planting. If you decide to save the tubers to plant again next year, store them in a cool place and plant them outdoors when the danger of a late heavy frost is past. Plants from a nursery or garden center should be planted at the same depth they were growing in their container.
Dahlias are heavy feeders in the garden, so feed them every couple of weeks with a balanced, all-purpose fertilizer. Water the plants during dry weather. Plants growing in containers may need daily watering during hot weather, depending on the size of the pot. Tall varieties may need staking. Clip off faded flowers to keep the plants blooming freely. And enjoy those beautiful colors all summer and into the fall!
