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Coral Bells to Heliopsis

Common Name Height (in) Space (ft) Flower Colors Flowering
Coral Bells (Alumroot) 12-24 1 Pink, Red, White May-August

Coral BellsHeuchera plants are compact, bushy and grow in tufts; basal rosettes of evergreen to semi-evergreen metalic heart-shaped green or purple-bronze leaves that look nice all season. Wiry stems of very small, pendant, bell-shaped flowers borne on graceful panicles; 6 weeks of bloom. Dead head to extend bloom; good cut flower. Green leafed forms prefer full sun; purple leafed do better in semi to full shade. Sun to  shade; reduced flowering in partial shade. Drought tolerant but likes to be watered. Prefers alkaline soil with good drainage; high in organic matter. Heavy wet clay soil can be a problem. Use a winter mulch to prevent soil heaving. Tends to weaken with age. Most effective when planted in mass.

Common Name Height (in) Space (ft) Flower Colors Flowering
Coreopsis 10-24 1 Yellow June-August

CoreopsisHas flowers borne on strong, wiry, graceful stems; single or double daisy-like flowers. Dead head to extend bloom; late to emerge in spring. Prefers full sun and well drained soil; drought tolerant once established. Slight winter protection is recommended. Best in groups of 3 or more. `Moonbeam' and `Zagreb' are good cultivars.
 

Common Name Height (in) Space (in) Flower Colors Flowering
Crocus 4-8 3-4 Various April

CroccusPlant in large groups for best color effect; first to bloom in spring. Foliage dies back by mid summer. Winter protection is helpful. Prefers sun to partial shade; don't like heavy poorly drained soil. May be kept in same spot for years.

 

Common Name Height (in) Space (ft) Flower Colors Flowering
Cushion Spurge 15-18 1.5 Green May-June

Cushion SpurgeEuphorbia epithymoides has chartreuse-yellow flower bracts that last for weeks; pale green foliage turns reddish in the fall. Milky sap can cause skin irritation. Full sun; tolerates dry, somewhat lean soil once established. Self seeds but not weedy.

 

Common Name Height (in) Space (in) Flower Colors Flowering
Daffodil 6-18 4-8 Orange, White, Yellow April-May

DaffodilPlants can be single, double or multi-flowered. Double nosed bulbs produce two flowers. Foliage dies back by mid-late summer; bulbs will rot if too wet.  Winter mulching is beneficial. Prefers moist well drained organic soil; fertilize sparingly. Needs full sun to partial shade. Plant in September; need 6 weeks to root. Very attractive when planted in mass; all at the same depth.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Daylily 12-48 1.5-2 Various June-August

Yellow DayliliesHemerocallus sp. has long narrow grass-like leaves with flower stems extending up above the leaves. Great diversity in plant size and flower form; single or double. Each flower lasts only one day but many flower stalks per plant; bloom for 3-4 weeks. Some cultivars bloom at night. Random bloomers; don't start at either the top or bottom of flower stalk. Remove spent blooms; don't allow seed to set. Prefer sun to partial shade and medium rich, moist soil high in organic matter; avoid soggy wet areas. Provide extra water during dry periods. Newer varieties form clumps; old fashion types are more spreading and almost weedy. Good planted in mass or as individuals. One of the lowest maintenance perennials.`Stella d'Oro' is short, has bright yellow flowers and blooms on and off throughout the summer. `Mary Todd' is one of the best; 2-2.5' tall with sturdy stems and wide flower petals.

Common Name Height (in) Space (ft) Flower Colors Flowering
Delphinium 12-60 1-2 Various June & Sept

Blue Spring DelphiniumVery showy flowers on open branched long spikes above clumps of divided or deeply lobed leaves. Stems tend to be hollow and brittle; may require staking if in wind. For rebloom, cut back just below spent flowers and fertilize plant. When new growth is 6" high, remove old foliage. Prefer sun to partial shade and well drained soil; high in organic matter. Tend to rot in heavy wet soil. Needs regular feeding and ample water. Mulch in summer to keep roots cool. Slugs, mites and mildew can be a problem. Plants lose their vigor after 2-3 years. Plant with crown 1-2" below soil level.

Common Name Height (in) Space (ft) Flower Colors Flowering
Echinacea 24-30 1-1.5 Pink, Purple, White July-August

Bravado EchinaceaPurple Coneflower has daisy-like blooms and dark green lance-shared leaves. Flowers well in summer heat; deadhead to prolong bloom. Attractive to butterflies. Seed heads attract goldfinches; add to the winter scene. One of the best August flowering perennials. Prefers full to partial shade and well drained soil, especially in earl spring. Tolerates heat, drought and wind. Roots are used as a medicinal herb to stimulate the immune system and treat colds.

Common Name Height (in) Space (ft) Flower Colors Flowering
Erigeron (Fleabane) 20-30 1 Various June-July

Azure Fairy ErigeronFlowers are similar in appearance to fall blooming asters. Clumps of basal foliage and 1-1 1/2 inch daisy-like flowers with yellow centers; good cut flower. Prefer full sun to patial shade and somewhat lean soil; partial shade will prolong bloom. Shear back to encourage rebloom; taller plants may need staking. Prefer cool summers. Good drainage is important for winter survival.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Eryngium (Sea-holly) 18-24 1-1.5 Blue July-August

Globose heads of small tightly packed flowers surrounded by a collar of stiff bracts. Lobed or deeply cut foliage is rigid, spiny and silvery in color; thistle-like. Used in fresh and dry arrangements. Prefers full sun. Tolerates poor dry soil and high salt levels; will not tolerate poor winter drainage.

Common Name Height (in) Space (ft) Flower Colors Flowering
Feverfew 12-24 1 White, Yellow June-August

FeverfewTanacetum parthenium has mum-like foliage; strongly aromatic. Very small daisy-like flowers; single or double. For compact growth, shear when 1' tall. Best in full sun to partial shadeand moist fertile soil. Short lived; self seeds.

 

Common Name Height (in) Space (ft) Flower Colors Flowering
Flax 10-18 1-1.5 Blue, White, Yellow May- July

Perennial FlaxLinum sp. has feathery bluish green foliage and wiry flower stems; blooms for about 6 weeks. Each flower only lasts one day; flowers remain closed on cloudy days. Prune back after flowering to maintain plant form. Prefers full sun and lean to medium fertile soil. Drought tolerant once established; doesn't like cold wet soil in spring. Mulch lightly for winter. Short lived; may self seed.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Flowering Onion 6-30 .5 Various May- August

Flowering OnionAlliums have a clump forming habit and flower head made up of many small flowers with membranous bracts around flower clusters. Deadhead before seed is released; self seeding can be a nuisance. Damaged foliage gives off an odor. Plant in groups; planting depth 3 times bulb diameter. Needs full sun and well drained soil; high in organic matter. Plant bulbs in the fall. Lily Leeks have 10-15" flower stalks, golden yellow blooms in June, and large flat leaves. Garlic Chives reach 20" in height, have white blooms in August and are good for cutting.

Common Name Height (in) Space (ft) Flower Colors Flowering
Gas Plant 30 2-3 Pink, White May

White Gas PlantDictamnus albus has glossy, leathery dark green leaves which remain attractive through the year; flowers on 2-3 foot spikes. Flowers give off a gas (gas plant). Leaves, flowers and seeds emit a lemon fragrance. Ripe seed pods will shoot seeds out to 10'. Prefers moist well drained soil high in organic matter. Plants don't like to be disturbed. Three to five years from seed to bloom.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Geranium (Crane's Bill) 6-20 1 Various May-August

Geranium sanguineumPlants vary greatly in stature and growth habit; have thick spreading rhizomes. Dark grayish-green palmate-shaped leaves and 1-2" mostly single flowers. Dead head to extend bloom. Fruit shaped like a cranes beak or bill. Some have scented foliage; some have red-orange fall color. Prefers full sun to partial shade and lean to medium fertile well drained soil; high in organic matter. Tolerates drought; doesn't like to be disturbed. G. sanguineum is very attractive.

Common Name Height (in) Space (ft) Flower Colors Flowering
Globe Thistle 18-42 2-3 Blue, Red July

Globe ThistleEchinops sp. has silvery white, thistle-like foliage; globular thistle-like flowers. Don't allow to seed; can be a real nuisance. If foliage deteriorates after flowering, cut back to ground level. Tolerates heat and drought; doesn't like wet soil. Prefers full sun and lean soil.  In rich soil may need staking; can be left undisturbed for years.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Goat's Beard 36-48 2-3 White June

Goats BeardAruncus sp has small white flowers on long open plumes; male and female flowers are on different plants. Compound feathery dark green 24-36" long leaves; flowers and foliage resemble the astilbe. Leaves turn bronze in the fall; bronze seed pods are used in dried arrangements. Prefers fertile soil and fairly moist conditions. Best in partial shade; will withstand full sun if kept moist.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Golden Marguerite 18-30 1-1.5 Orange, Yellow June-July

Gilden MargueriteAnthemis tinctoria has greyish green feathery foliage with daisy-like flowers; slightly aromatic. Older flowering stems can be cut down to encourage new basal growth. Prefers full sun and lean soil. Tolerates heat, drought and poor soil; may winter kill in wet soil. Self seeds; can get weedy.
 

Common Name Height (in) Space (ft) Flower Colors Flowering
Goldenrod 12-60 1.5 White, Yellow August-Sept

Golden Baby GoldenrodSolidago sp. forms clumps with somewhat arching stems; individual flowers are very small and borne in clusters. Prefer moist well drained soil; drought tolerant. Fertile soils may promote rapid growth, weediness, and flopping stems. Self seeds; may become invasive. Goldenrod has a reputation for causing hayfever but it is not the culprit.
 

Common Name Height (in) Space (in) Flower Colors Flowering
Grape Hyacinth 6-10 3-4 Blue, White April-May

Grape HyacinthMuscari sp. is very effective when used with daffodils. Tiny bell-shaped flowers look like an upside down bunches of grapes. Bloom just after the crocus. Multiples to form large beds; plant in late September or early October. Sun to partial shade and medium fertile soil.

 

Common Name Height (in) Space (ft) Flower Colors Flowering
Heliopsis 36-48 2-3 Yellow July- August

HeliopsisSingle, semi-double or double daisy-like flowers; deadhead to extend bloom period. Leaves are 4-5" long, dark green, and rough to the touch; taller cultivars may require support. Grows well in sun to partial shade and moist well drained or dry soil; dislikes long dry periods. Tends to flop in rich soil. Self seeds.


Todd Weinmann, Extension Horticulturist & Master Gardener Coordinator
Phone: (701) 241-5707
E-mail: todd.weinmann@ndsu.edu

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