Best [dahlia](/plants/dahlia-care/) cultivars by size and form

Dahlias are summer-to-fall blooming plants grown from tuberous roots. They are tender perennials -- reliably perennial only in zones 8--11 where ground doesn't freeze. In zones 3--7, tubers must be dug in fall and stored indoors, or treated as annuals with new tuber purchase each.

—- title: "Best dahlia cultivars by size and form" slug: best-dahlia-cultivars hub: plants category: "Cultivar guide" description: "Top dahlia cultivars organized by form and size — dinnerplate, ball, waterlily, and single types — with realistic expectations for storage, tubers, and zone performance." date: 2026-06-10 updated: 2026-06-10 author: "Thomas A." reading_time: 7 scientific: "Dahlia" zones_min: 3 zones_max: 11 sun: "full sun" —-

Dahlias are summer-to-fall blooming plants grown from tuberous roots. They are tender perennials — reliably perennial only in zones 8—11 where ground doesn't freeze. In zones 3—7, tubers must be dug in fall and stored indoors, or treated as annuals with new tuber purchase each spring.

I don't grow dahlias at home. The deer pressure and the annual digging/storage requirement make them lower priority than the perennials I've committed to. This guide draws on the American Dahlia Society's classification system and Extension data.

Dahlia classification

Per the American Dahlia Society, dahlias are classified by flower form and size. Key forms:

• AA (Giant): over 10 in diameter
• A (Large): 8—10 in
• B (Medium): 6—8 in
• BB (Small): 4—6 in
• M (Miniature): under 4 in
• P (Pompom): under 2 in, fully double, globe-shaped

Forms by petal arrangement:

• Formal decorative: fully double, evenly arranged, formal appearance
• Informal decorative: fully double, irregular petal arrangement
• Ball: more than 2 in; rounded, fully double; petals blunt-tipped
• Pompom: under 2 in; fully rounded globe
• Waterlily: fully double, petals wide and flat, shallow flower resembling waterlily
• Cactus: petals rolled back into quills
• Single: one row of petals with visible center

Dinnerplate dahlias (size AA/A)

Dinnerplate dahlias produce flowers 8—12 inches across. They require staking, pinching, and disbudding (removing smaller buds to concentrate energy into the main bloom) to achieve catalog-size flowers.

'Café au Lait'

Form: Informal decorative Flower size: Large (8—10 in) Color: Cream-blush-peach, variable

Per Missouri Botanical Garden, 'Café au Lait' is the most photographed dahlia on social media and one of the most requested wedding flowers. The muted cream-to-blush color photographs beautifully. It is not the most vigorous dahlia — 'Café au Lait' plants are less productive per tuber than ball or pompom types, and the large flowers are prone to petal damage in rain. Worth growing if the color palette is your priority; expect lower total flower count than smaller-form types.

'Thomas Edison'

Form: Formal decorative Flower size: Large (8—10 in) Color: Deep purple

Per the American Dahlia Society's award records, 'Thomas Edison' has one of the longest continuous show records of any dahlia cultivar. Deep purple, large, formal. Vigorous tuber production makes it easy to divide and expand plantings.

'Bishop of Llandaff'

Form: Peony (semi-double) Flower size: Medium (3—4 in) Color: Deep red with prominent yellow center Foliage: Dark bronze-black

Per NC State Extension, 'Bishop of Llandaff' is one of the most valuable dahlias for mixed borders because the dark bronze foliage provides ornamental interest even when not in bloom. The semi-double red flowers with bright yellow centers are excellent for pollinators. It is not a large-flowered type — medium flowers on a plant that earns its place through foliage and consistent bloom.

Ball and pompom dahlias

Per Penn State Extension, ball and pompom dahlias bloom more prolifically per plant than large decorative types because each stem terminates in a smaller flower that forms faster. They are easier to grow to catalog quality without the disbudding required for dinnerplate types.

'Cornel Bronze' (ball)

Form: Ball Flower size: 3—4 in Color: Orange-bronze

A ball dahlia in an unusual orange-bronze tone. Per the American Dahlia Society, ball dahlias are among the most consistent cut-flower dahlias because the rounded form holds well after cutting and the petals are tightly packed.

'Jowey Winnie' (ball)

Form: Ball Flower size: 3—4 in Color: Deep rose-pink

Per NC State Extension, ball dahlias like 'Jowey Winnie' produce one of the best stem-to-flower ratios for cutting gardens. The compact rounded flowers are less affected by rain and wind than large decorative types.

'Wizard of Oz' (pompom)

Form: Pompom Flower size: 2 in Color: White with pink tips

Per Missouri Botanical Garden, pompom dahlias produce the highest number of flowers per plant of any dahlia form because of the small flower size. They are the best choice for gardeners who want volume of flowers rather than spectacle.

Waterlily and anemone forms

'Cameo' (waterlily)

Form: Waterlily Flower size: Medium (4—6 in) Color: Cream-peach

Per the American Dahlia Society, waterlily dahlias have the most elegant appearance of any dahlia form and are among the most photographed types for wedding and event work after 'Café au Lait'. The flat, wide petals resemble an actual waterlily flower. Good for cutting.

'Totally Tangerine' (anemone)

Form: Anemone Flower size: Small (3—4 in) Color: Orange-tangerine Notable trait: Excellent pollinator plant; accessible center for bees

Per UMass Extension, single and anemone-form dahlias are the best choices for supporting pollinators. The accessible center ring of short florets around the eye provides pollen and nectar that is physically inaccessible in fully double forms.

Tuber storage

Per Penn State Extension, in zones 3—7, dig dahlia tubers after the first killing frost (typically late October—early November in zones 5—6):

1. Cut stems back to 4—6 inches
2. Dig the clump carefully — tubers bruise easily
3. Allow to dry in open air for 24—48 hours
4. Pack in slightly moist peat, vermiculite, or newspaper in a cardboard box
5. Store at 40—50°F in a frost-free location
6. Check monthly; discard any rotting tubers immediately to prevent spread

Per NC State Extension, storage failures are most often caused by temperatures too warm (above 55°F causes premature sprouting) or too wet (causes rot). A basement at 45°F is ideal. An attached garage in zones 5—6 may freeze overnight in deep winter — monitor temperatures.

Growing from tubers vs. seed

Per Penn State Extension, named dahlia cultivars are grown from tubers, not seed. Seed-grown dahlias (commonly sold as 'Figaro' mix, 'Gallery' series, 'Opera' series) do not produce tubers reliably and are typically treated as annuals. Named cultivars — all the selections discussed above — must be grown from tubers to produce true-to-type plants.

Common problems

Frequently asked questions

When should I plant dahlia tubers? Per Penn State Extension, plant tubers after the last frost date when soil has warmed to 60°F. In zones 5—6, this is typically mid-May. Earlier planting in cold soil causes the tuber to rot rather than sprout. Set tubers horizontally, 4—6 inches deep, with the "eye" (growth bud) facing upward.

Do dahlias need to be staked? Per NC State Extension, all large-flowered (dinnerplate) dahlias and most tall decorative types need staking. Set a 6-foot stake at planting time (before growth begins) and tie stems as they grow. Ball and pompom types on shorter plants typically don't need staking.

How often should dahlias be watered? Per Penn State Extension, established dahlia plants need 1—2 inches of water per week during the growing season. Overwatering tubers before growth emerges causes rot. Once stems are 12—18 inches tall, consistent water promotes continuous bloom. Mulch to 3 inches helps retain moisture and regulate soil temperature.

Sources

1. NC State Extension — Dahlia
2. Penn State Extension — Dahlias
3. Missouri Botanical Garden — Dahlia
4. UMass Extension — Dahlias for Pollinators
5. American Dahlia Society — Classification System