GROWING DIANTHUS FLOWERS IN YOUR GARDEN

When to plant:

Planting times depend on the type you're planting.

• Perennial types: Plant during cooler months in early spring or fall.
• Biennials and annuals: Plant nursery starts outside in spring, or sow seed indoors 6 to 8 weeks before your last frost date for bloom the same year.
• Seeds sown directly in the garden in late spring or summer will bloom the following year.

Where to plant:

Choose a site with rich, well-draining soil in full to part sun. Plants will bloom best in full sun; too much shade can result in fewer flowers and crown rot.

How to plant:

Here's a basic planting overview.

1. Place plants 6 to 12 inches apart, depending on the variety.
2. Loosen soil to a depth of 12 inches and mix in 2 to 4 inches of compost.
3. Dig a hole twice the diameter of the root ball and place the plant in the hole so the top of the root ball is level with the soil.
4. Gently tamp soil around the base of the plant and water well.

Deadheading:

Deadhead (cut off spent blooms). Removing spent flowers encourages new flowers.

Dividing:

Older plants may develop dead spots in the center of the foliage, which means it’s time to divide. Cut clumps into several pieces, removing the dead foliage, and transplant divisions to new spots. (Learn more on how & when to divide perennials.)

Soil:

Carnations, sweet William, and cottage pinks do best in rich, well-draining soil that’s kept moist but not soggy. Alpine types, such as cheddar pinks, prefer a slightly alkaline, sandy soil with sharp drainage.

Amendments & fertilizer:

Here are several guidelines for making sure your dianthus get the nutrients they need.

• For established perennials, apply a thin layer of compost in spring and sidedress with a well-balanced fertilizer according to instructions.
• Avoid organic mulch, as it can contribute to rot or fungal problems; instead, use gravel or stone chips to suppress weeds.
• For biennials or annuals, apply a liquid fertilizer monthly during bloom time.

Watering:

Water once a week in summer, or more frequently in hot weather if needed. Avoid overwatering, which can cause rot. Overhead watering may cause leaf mildew.

Staking:

Carnation types with long stems may need staking to keep them from falling over.

Diseases and pests:

In addition to being easy to care for, dianthus are free of most pests and diseases when healthy and planted in the ideal site. Just like any plant, though, there are potential problems that can occur.

• Overwatering or heavy mulch can cause crown rot.
• Poor drainage can result in stem rot or root rot.
• Insect problems can include slugs and snails, sow bugs, spider mites, or grasshoppers.

With so many choices, here are some factors to consider.

For bedding displays and borders:

Edge the front of a border with low-growing perennial varieties. Sprinkle annual or biennial seeds to fill in gaps between established perennials.

For containers, rock gardens, and small yards:

Dwarf and mat-forming types will stay smaller and not overwhelm a space. Combine in containers, rockeries, or beds with other small annuals or perennials that thrive in the same growing conditions.

For cutting gardens and large-scale landscapes:

Choose Sweet William or carnation varieties that will grow tall and plant them in rows or masses for the greatest visual impact. The stately stems and long bloom time make these suitable for floral arrangements.

For areas of the garden that you want to keep low maintenance:

Be sure to choose a perennial so they come back every year. Good choices include D. gratianopolitanus, D. plumarius, D. barbatus, and D. chinensis.

With so many choices, here are some tips to consider.

For bedding displays and borders:

Edge the front of a border with low-growing perennial varieties. Sprinkle annual or biennial seeds to fill in gaps between established perennials.

For containers, rock gardens, and small yards:

Dwarf and mat-forming types will stay smaller and not overwhelm a space. Combine in containers, rockeries, or beds with other small annuals or perennials that thrive in the same growing conditions.

For cutting gardens and large-scale landscapes:

Choose Sweet William or carnation varieties that will grow tall and plant them in rows or masses for the greatest visual impact. The stately stems and long bloom time make these suitable for floral arrangements.