Upper Midwest

• Easy, Hardy Rockgarden Plants
• Advanced Plants

Easy, Hardy Rockgarden Plants

Achillea tomentosa 'Nana'

This is a miniature plant that has soft yellow heads and tiny fragrant leaves. Another is 'Maynard’s Gold’, a dwarf golden yarrow with silvery leaves that makes a good ground cover.

Allium cyaneum

This has bright blue flowers in early summer.

Allium senescens glaucum

Has neat pink flowers in August.

Allium thunbergii ‘Ozawa’

This is one of the latest alliums to flower with clusters of purple bellflowers.

Androsace primuloides ‘Chumbyi’

3"x6"; downy rosettes with lavender-pink flowers like tiny primroses.

Androsace sarmentosa

This is a small evergreen rosette. The flower pushes up, in late spring, a single stem with a cluster of pink. A plant that spreads by stolens and forms a solid mat.

Antennaria neglecta, A. neglecta var. gaspensis, A. rosea var. confinis, A. dioica

These plants consist of silver one-inch mats with white or pink flowers resembling tiny tufts of soft fur (Pussytoes).

Aquilegia flabellata 'Nana'

This is a dwarf columbine 10-15 cm high. It has bluish-green foliage and produces large blue and white bi-colored flowers held just above the foliage. White and pink forms also exist. They can self-seed but deadheading will curb this habit.

Arabis species

These plants have mat-forming foliage and fragrant white or pink flowers in spring.

Aster alpinus

There are a number of varieties of daisy like-flowers. Size is 6 to 8 inches. ‘Dark Beauty’ is a spring aster with deep violet blue flowers with gold centers. ‘Happy End’ is a pink daisy with yellow centers which blooms May & June and sometimes re-blooms in the fall.

Aubrieta deltoidea

This cress forms a trailing mat of foliage. Its flowers have four petals and range from pink to purple. The plants like full sun.

Campanula 'Samantha'

This has a violet/lavender bloom that develops in late spring or early summer. The flower is not a bell like most Campanulas and holds its flower upright. The plant is about 6 inches tall. Many more Campanulas are also easy to grow.

Delosperma congestum 'Gold nugget'

'Gold Nugget' is a true alpine succulent, 1/2” x 8” that has shiny yellow flowers that sit on top of the foliage. It likes some afternoon shade where the summers are hot.

Dianthus deltoides

This plant is sometimes called Maiden Pinks. The flowers range from white to pink to red with a touch of purple. Deadheading reduces the spread of seedlings. There are also many other Dianthus that are easy plants. Typical are the small cushion-forming types like ‘Tiny Rubies’, ‘Firewitch’ and ‘Artic Fire’.

Draba species

These plants are extremely early, usually with yellow blooms and evergreen foliage.

Festuca ovina, F. amethystina, F. valeriaca

These plants have stiff blue grassy leaves may be evergreen.

Gentiana septemfida

Adaptable to regular garden soils with true blue flowers. 6 inches x 1 foot.

Gypsophila repens

This is a creeping Baby Breath that produces many small pink flowers in the late spring. The size at maturity is 4” by 1 foot.

Iberis sempervirens 'Little Gem'

The common name is Candytuft. It has white flowers on top of evergreen-like foliage in May or June.

Penstemon hirsutus pygmaeus ‘Albus’

Sprays of white flowers cover these small 4-inch plants in May or June.

Penstemon pinifolius

This is an outstanding variety but often overlooked. It blooms for 6 to 8 weeks in midsummer with profuse tubular orange flowers. It is long-lived and grows easily in both xeric and traditional perennial gardens. On mature plants the stems become woody with bright green needle-like foliage.

Pulsatilla vulgaris

Delightfully furry flower buds give rise to many color forms. 1-1.5 ft x 1ft. Reseeds prolifically if allowed.

Sedum species (many varieties)

Also called stonecrop, they have stems that root to spread. The stems have a round succulent look. Leaf color is green, bluish or red and some are variegated. Flowers can be white, pink, red or yellow.

Sempervivum species

Many varieties such as S. 'Cobweb, S. 'Rollers, S. 'Ashes of Roses. In general, have succulent leaves arranged in a rosette-like pattern. The flowers are unique in a variety of colors.

Silene alpestris

Dainty white flowers with five scalloped petals, over low-growing narrow-leaf foliage.

Silene dioica ‘Flore Pleno’

Double red campion with green middles to the flowers. Plant is about 6 inches in height.

Silene schafta

This is one of the most popular plants for a rockery. It flowers when others are finished. It has bright green pointed leaves and bright magenta flowers.

Silene splendens

Has gray-green leaves and fuchsia-colored flowers that appear from late spring to summer.

Sisyrinchium angustifolium

The common name is Blue-eyed grass. It has starry light blue flowers on top of slender green leaves. It is about 8 inches tall.

Thymus 'Bressingham'

This is an excellent 4-inch high groundcover. The flowers are many and the color is a lavender-pink. There are also many other Thymus species that are easy to grow.

Veronica ‘Waterperry’

This is a creeping plant, 4-6 inches high with multi-tone blue flowers. Makes a good ground cover. There are a number of other Veronicas such as V. prostrata, V. schmidtii, V. gentianoides. They all have blue/violet flowers and are low-growing.

Advanced Plants

Cerastium alpinum

Full sun and no crowding is essential for proper growth.

Claytonia sibirica

Woodland flower. Reseeds.

Corydalis solida

Goes dormant in early summer. Produces small, winter hardy tubers.

Coryphantha vivipara

Ball cactus. Hard to find but easy to grow. Tolerates humidity and excess moisture well.

Delosperma basuticum

Compact, yellow flowers with white eye. Easier to grow than D. nubigenum.

Dracocephalum botryoides, D. palmatum

The cutest little silver foliage for troughs. Purple flowers.

Iris suaveolens, Iris reichenbachii

Dwarf bearded iris for dry areas.

Lewisia cotyledon, L. ‘Little Plum’

Provide some shade.

Mertensia alpina

Part shade.

Orostachys spinosa

Similar to Hen and Chicks. Shrinks to a silver ball during winter.

Primula wulfeniana

Very small, evergreen, likes alkaline soil. Very adaptable.

Ruellia humilis

Wild petunia but not tuberous or invasive. Lavender flowers.

Salix repens

A dwarf willow. Very decorative catkins in early spring.

Silene acaulis

Tight, small, firm, evergreen bun, pink stemless flowers.

Veronica oltensis, V. liwanensis, V. pectinata

All very low mat-forming. Blue flowers, need good drainage.

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