How to Grow and Care for Daylilies, a Low-Maintenance Perennial to Plant in Your Summer Garden

Colorful and dainty, daylilies (Hemerocallis) are perennials that bloom during the summer months. The plant gets its name because the flowers only last one day each (but you can have many different flowers emerging off a single stem for weeks of blooms). Daylilies are durable and adaptable plants that require little maintenance once established. Plant them in an area of your garden with plenty of sunlight and nutrient-rich soil, and watch as they bloom year after year. To ensure this plant thrives in your landscape, we spoke to experts who explain everything you need to know about growing and caring for daylilies.

When to Plant Daylilies

Early spring or fall is the best time to plant daylilies. "Plant in spring as soon as the soil can be worked and in fall six weeks before the frost," says Linda Langelo, horticulture specialist at Colorado State University. "Planting in early spring allows the roots to be well-developed before winter. A well-developed root system ensures better survival during the winter months."

How to Plant Daylilies

Planting daylilies in your garden is straightforward and can be done from seed or container.

From Seed

Direct sow daylilies by seed in early spring or fall for best results. "The seed should germinate between 7 to 14 days," says Langelo.

1. Amend the soil with organic matter, like compost.
2. Dig a row about 1/2- to 3/4-inch deep.
3. Place seeds in the row, spacing each seed about 4 to 6 inches apart.
4. Water the soil so that it is moist.
5. Place a 2-inch mulch over the seeded row.

From Container

If you purchased an already blooming daylily from your local nursery, plant it using the following method outlined by Melinda Myers, gardening expert and host of the Great Courses How to Grow Anything DVD series.

1. Amend the soil with organic matter, like compost.
2. Dig a hole wide enough to accomodate the roots.
3. Set the plant in the hole so the crown (the area where the plant's roots join its leaves) is about 1 inch below the soil surface.
4. Fill the hole with soil.
5. Water thoroughly to help remove any air pockets and settle the soil.

How to Care for Daylilies

Daylilies are easy to care for, but there are some things to keep in mind to ensure they thrive in your garden.

Sunlight

Daylilies require at least six or more hours of direct sunlight a day to grow to their fullest potential. "If you live in a hotter region, a bit of afternoon shade can help keep the flowers looking their best," says Myers. "However, too much shade might cause the foliage to flop and the plants to fail to bloom."

Soil

While they can survive in a range of soils, daylilies prefer organic-rich, loamy soil. Before planting, work compost into the soil to improve drainage, says Myers.

Water

Daylilies prefer weekly watering to ensure a vigorous bloom. "Whether from rainfall, irrigation, or a combination of the two, daylilies thrive with about an inch of water a week," says Myers. "You will need to water less when temperatures are cool and the soil is mulched."

Temperature

Daylilies can withstand a range of climate conditions, but they prefer temperatures of around 60 to 75 degrees Fahrenheit.

Fertilizer

Give daylilies a light application of a balanced fertilizer during spring. "If you over-fertilize a daylily, the vegetative growth is excessive and weak," says Langelo. "This decreases blooms on the daylily. Since they only last a day, you want as many flowers as possible."

How to Prune Daylilies

Cut back your daylilies to the ground in fall or early spring before new growth emerges, says Langelo. After daylilies bloom, remove spent flowers and foliage to keep them healthy and prevent the spread of disease. If you don't do this, your daylilies will put their energy into producing seed pods rather than growing more blooms.

How to Divide Daylilies

Dividing a daylily is best done in late summer or early fall. "The most common method is dividing by root clump," says Langelo.

1. Using a digging fork, loosen the soil around the entire plant.
2. Gently remove the root ball from the soil.
3. Rinse the soil off the roots so you can see them better.
4. Separate the clump into smaller fans (the greens connected to the roots), making sure each clump has about three fans of leaves and a healthy set of roots.
5. Cut the rhizomes connecting the fans.
6. Amend the soil with some organic matter.
7. Dig a hole and place a divided clump into the hole. Repeat with the remaining clumps.
   

Common Problems With Daylilies

Daylilies are hardy plants that are generally resistant to diseases and pests, but there are some problems you may encounter.

Thrips

Thrips can sometimes feed on the flower buds of daylilies. Control thrips by wiping the foliage periodically with insecticidal soap and cutting off any buds or foliage that have damage.

Spider Mites

Spider mites pierce the undersurface of the leaves with their mouthparts and suck from the plant. In turn, the leaf surfaces develop pale speckling. "Take a magnifying lens, and you will notice tiny round eggs," says Langelo. "Preventing drought stress and frequently spraying the undersides of the leaves will help eliminate spider mites."

Rust

Rust is a fungus that creates orange-yellow powdery leaves. "If you rub your finger over the spot, you will have a powdery substance on your finger that looks like rust," says Langelo. To prevent this, minimize overhead watering and promote good air circulation.

Leaf Streak

Leaf streak is caused by a fungus called Aureobasidum microstictum, says Langelo. The foliage dies back and will have brown spots and yellow streaking. This is transmitted by pests or frost damage and can be treated with a fungicide.