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Achillea to Columbine

Common Name

Height (in)

Space (ft)

Flower Colors

Flowering

Achillea

1-1.5

filipendula (fern-leaf)

24-36

Yellow July-August
millefolium (common)

12-24

Pink,Red,White

July-August

ptarmica (sneezewort)

18-24

White

Cornation Gold AchilleaGrayish-green to green, fine textured aromatic foliage; good for contrast. Flat compound flower heads are made up of tiny "daisies" packed together; good cut flower. May rebloom if deadheaded. Heat and drought tolerant; needs good drainage and prefers full sun and lean soil. A. millefolium and A. ptarmica spread rapidly and tend to be weedy. `The Pearl' has button-like flowers in branching heads.
 

Ajuga (see Ground Covers)

Common Name Height (in) Space (ft) Flower Colors Flowering
`Silver Mound' Artemisia 12-15 1-1.5 Insignificant -----

Silver Mound ArtemesiaSilver-gray foliage, mound shaped and aromatic (sage smell); good accent plant. Needs good drainage; may rot in wet soil. Full sun and dry conditions; flops in rich soil. Shear back in mid-June or before flowering to prevent plant from opening up.

Common Name Height (in) Space (ft) Flower Colors Flowering
Astilibe 6-24 1.5 Red,White,Purple, Pink June-August

Bridal Veil AstilibeDelicate fern-like leaves are divided and compound; small flowers are borne on fluffy, dense panicle above foliage. Deadheading doesn't prolong flowering. Likes good moisture and cool conditions; won't tolerate hot dry conditions. Does well on the north side if no other shading is present; partial to full shade. Medium to high water need, but won't tolerate wet soil in winter. Prefers moderately rich soil; benefits from extra fertilizer in the summer. Mites can be a problem.Best when planted in groups of three or masses. If doing poorly move to a new location.

Common Name Height (in) Space (ft) Flower Colors Flowering
Baby's Breath 18-30 2 White,Pink July

Baby's BreathGypsophilia paniculata has grass-like bluish green foliage with minutely branched wiry stems; single or double flowers. Season is too short for rebloom; good as a cut flower or as a filler in dried arrangements. Stake in windy or exposed areas. Prefers full sun and alkaline soil which is not too heavy or rich; drought tolerant once established. Mulch for the winter. Tends to be short lived in heavy soils. Plant joint 1" below soil surface. Has naturalized and became a weed problem in some areas. Creeping form available. `Bristol Fairy' has double flowers; sterile.

Common Name Height (in) Space (ft) Flower Colors Flowering
Balloon Flower 9-30 1-1.5 Blue,White,Pink July-Sept

Ballon FlowerPlatycodon grandiflorum has bell-shaped flowers that swell up like a balloon before opening; single, semi-double or double flowers. Dead head for a longer bloom; good cut flower. Leaves have a leathery appearance and are glaucous on the undersides. Bushier if pinch back when stalks are 6" high; tall forms may need staking. Slow to emerge in the spring. Needs well drained soil or the roots will rot. Blues do better in full sun. Whites and pinks will tolerate more shade. Don't like to be moved. `Sentimental Blue' is a good cultivar; 9" tall.

Common Name Height (in) Space (ft) Flower Colors Flowering
Bellflower
Carpathian (carpatica) 6-12 .5-1 Blue,White June-August
Clustered (glomerata) 15-18 1-1.5 Blue,Pink,White June-July
Peachleaf (persicifolia) 18-24 1 Blue,White June-July

Carpathian BellflowerCampanula carpatica grows in dense tufts covered with bell-shaped flowers on wiry stems. Deadhead to get bloom most of the summer. Mulch in summer to keep roots cool; may need extra water in August. Prefers sun to partial shade and well drained, semi-rich organic soil; tends to be short lived. `Blue Clips' and `White Clips' have larger flowers. C. glomerata has lance-shaped leaves and dense umbels of funnel-shaped flowers. Prefers sun but takes shade well; spreads rapidly in moist areas. Some are very aggressive and weedy. Select a non aggressive cultivar such as `Joan Elliott'  is an excellent cultivar; good cut flower. C. persicifolia has outward facing bell-shaped flowers and narrow peach- like leaves; best when planted in mass. Full sun to partial shade.

Common Name Height (in) Space (ft) Flower Colors Flowering
Bergenia 12-18 1-1.5 White,Pink,Red April-May

BergeniaBold cabbage-like, evergreen leaves; heart-shaped and waxy. Foliage turns reddish bronze in the fall; green in spring. Tiny flowers are produced on spikes resembling hyacinth; not real showy. Short bloom period; flowers lightly after a severe winter. Prefer fertile soil, high in organic matter; sun to shade. Likes areas of high to medium moisture levels but does well in dry shade under trees. Best grown in groups. Slugs can be a problem. Needs good winter protection.

Common Name Height (in) Space (ft) Flower Colors Flowering
Blanketflower 6-24 .5-1.5 Red,Yellow June-August

Goblin BlanketflowerGaillardia X grandiflora has basal hairy leaves and daisy-like bicolored flowers; deadhead to promote more flowering. Good cut flowers. Taller plants may need to be staked. Old plants produce more foliage and less flowers; centers tend to die out in winter causing plant to spread out. Late to emerge in the spring. Likes hot dry conditions; thrives in poor soil. Needs full sun and well drained soil; poor survival in heavy clay soil. Short lived here. Self seeds. `Baby Cole' and `Goblin' are excellent dwarf cultivars.

Common Name Height (in) Space (ft) Flower Colors Flowering
Bleeding Heart
 spectibilis 24-30 2 Pink,White May-June
 exima `luxuriant' 12-18 1.5 Red May-August

Bleeding HeartDicentra spectabilis has light green compound leaves with long graceful racemes of heart-shaped flowers; good cut flowers. Plants yellow and die down after flowering; foliage can be removed. Prefer partial to full shade and a cool moist soil rich in organic matter; long lived. `luxuriant' has ferny blue-green leaves and larger flowers. Foliage remains attractive all summer. More sun and heat tolerant than spectabilis. Don't do well here; short lived.

Common Name Height (in) Space (ft) Flower Colors Flowering
Boltonia 36-48 1.5-2 Purple,Pink,White August-Sept.

Snowbank BoltoniaResembles a tall aster but is less susceptible to mildew and more tolerant of heat and humidity. Has narrow blue-green leaves and 1" daisy-like flowers; may need staking. Tolerates drought well; spreads rapidly in moist areas. Prefers full sun to partial shade.

Common Name Height (in) Space (ft) Flower Colors Flowering
Brunnera (Bugloss) 12-18 1-1.5 Blue May-June

Siberian BuglossSiberian Forget-me-not has tiny star-like flowers with yellow eyes resemble forget-me-nots; produced in loose racemes. Flowers for 3-4 weeks. Dark green heart-shaped leaves are 6-8" long; neat tidy plant. Prefers moist, medium rich, well drained soil; best in partial shade.  Slugs haven’t been a problem. Centers die out over time; dig and divide. Variegated form has white margins and is vigorous; foliage looks good all season. Leaf edges scorch in full sun or drought.

Common Name Height (in) Space (ft) Flower Colors Flowering
Bugbane (Snakeroot) 36-72 1.5-2 White July-August

BugbaneCimicifuga racemosa has tall spike-like flower heads that resemble a narrow bottle brush; thrice divided, dark bronzy green foliage looks like astilibe. If planted in full sun, needs moist soil high in organic matter; prefers good moisture but fairly drought tolerant once established. Cultivars available with purplish foliage.

Common Name Height (in) Space (ft) Flower Colors Flowering
Butterfly Weed 18-30 1 Orange, Red, Yellow July-August

Butterfly WeedAscelepias tuberosa has rigid stems topped by flat umbels of bright flowers; brilliant when in mass. Very attractive to butterflies. May rebloom if deadheaded. Pods are used in dry arrangements. Late to emerge in the spring; don't remove by accident. Prefers full sun and well drained soil with low fertility; wet, heavy clay soil can be a problem. Tolerates heat and drought well because of it's deep tap root. Doesn't like to be moved or divided because of tap root.

Common Name Height (in) Space (ft) Flower Colors Flowering
Candytuff 6-12 1 White May-June

Iberis sempervirens produces a spreading mat of small leathery evergreen leaves; shear fading flowers to promote branching of plant. Good cut flowers; some cultivars are fragrant. Grows best in well drained soil especially in early spring; stops flowering if too dry. Sun to partial shade. Mulch for winter; tend to be short lived in heavy clay soils.

Common Name Height (in) Space (ft) Flower Colors Flowering
Chrysanthemum 8-30 1.5-2 Various July-September

ChrysanthemumDendranthema morifolium has a variety of colors and flower types; singles and doubles. Small cushion types are best for landscaping; large flowered best for cutting. Select varieties which flower before September 15th. Most Minnesota varieties are good. Can pinch terminal buds up to July 1; plants are bushier and set more buds. Many new cultivars don't need pinching. Day neutral cultivars will flower on and off through season if deadheaded. Prefers full sun and well drained, fairly fertile soil high in organic matter. Like regular watering; fertilize until flower color shows. Leave tops on for winter; need snow cover. White and yellow colors may have problem with thrips. Tarnish plant bugs can cause distorted flower heads. Short lived; lose vigor with age. Plant or transplant before May 15th. `Clara Curtis' (early; single, pink flower).

Common Name Height (in) Space (ft) Flower Colors Flowering
Columbine 9-30 1-1.5 Various May-July

ColumbineAquillegia sp. has nodding long slender stems of airy clusters of dainty multi-colored flowers; attract hummingbirds. Does well in sun to full shade and moist, fairly rich, well drained soil; high in organic matter. Feed after flowering; water until plant starts yellowing. Mulch for summer and to help overwinter. Short lived (2-4 yrs); Columbine Borer and crown rot are a problem especially in older plants. Leaf miners and mildew can also be a problem. Self seeds in moist soil.


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

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