From Boerner to Your Backyard

From Boerner to Your Backyard
2010 Garden Walks with Melinda Myers
Sponsored by Ground Covers and Vines
1. Combo Alert #1 Sage, Blue Globe Onion & Yarrow Salvia nemerosa ‘Blauhugel’, Allium caeruleum & Achillea ‘Moonshine’ Blue and yellow (opposite on the artist color wheel) make a dramatic statement in the garden.
2. Betty Corning Clematis – Clematis ‘Betty Corning’ This reliable clematis blooms for several months during the summer. The light blue bell shaped flowers create a nice backdrop for perennials, accent for fences and buildings and vertical accent in any planting bed. Grow clematis with “their face in the sun and feet in the shade” for best results. Prune summer and fall blooming clematis, if needed, during the dormant season. I prefer to wait until late winter so I can enjoy the winter interest and for increased winter hardiness. Early spring bloomers flower on the previous year’s growth and should be pruned, if needed, after flowering. This vine attaches by twining petioles. 3. Combo Alert #2 Sundrops, Tall Buttercup & Caucasus Geranium Oenothera fruticosa, Ranunculu acris ‘Flore Pleno’ & Geranium ibericum Three equally assertive plants weave together to create a riot of color. When creating long lasting combinations make sure the plants all prefer the same growing conditions and are equally assertive. These plants all thrive, as you can see, in this full sun location with well-­‐drained soil. Be aware that creeping buttercup (Ranunculus repens ‘Flore Pleno’) is often misidentified as tall buttercup (Ranunculus acris ‘Flore Pleno’). Creeping buttercup is much more aggressive than the tall buttercup seen here. 4. Chameleon Plant – Houttuynia cordata ‘Variegata’ (synonymous with ‘Chameleon’ & ‘Tricolor’) This plant seems to either thrive and take over or die. Many gardeners restrain the growth of this plant by growing it in a large pot sunk in the ground or using it as a groundcover in areas surrounded by concrete. Houttuynia tolerates wet sites in full sun or part shade. Take a whiff of the flowers. Some feel it is reminiscent of cheap perfume. 5. Dwarf Blanket Flower – Gaillardia x grandiflora ‘Goblin’ Blanket flowers are great for attracting butterflies and hot dry locations once established. They tend to die from wet feet in winter or bloom themselves to death. Make sure they are grown in soil with good drainage and northern gardeners may want to remove late season bloom to increase winter survival. 6. Ornamental Onion – Allium obliquum – lime green flower Use a mix of alliums to provide a season of color, texture and form in the garden * Other Alliums to watch for – Allium ‘Hair’ (note unique flower), Allium moly – yellow blooms 7. Combo Alert #3 Ornamental Onion, Tiger Eyes Sumac, Arkansas Amsonia Allium, Rhus typhina ‘Bailtiger’, Amsonia hubrichtii Sometimes it is all about the texture and form. A great example of using the bold form of allium with the lacy foliage of Tiger eye sumac and Arkansas amsonia. 8. Coronation Gold Yarrow – Achillea filipendulina ‘Coronation Gold’ Yarrows are very tolerant of hot dry conditions once established. I prefer the clump forming filipendulinas and hybrids that do not seed, spread and become weeds in the garden. The flowers are beautiful in the garden and can be used fresh or dried in arrangements. 9. Montrose Rose Yarrow – Achillea millefolium ‘Montrose Rose’ This cultivar of common yarrow is known for its compact habit and strong stems that are more resistant to wind and rain damage than others. It spreads by rhizomes and can form large colonies over time. Cut faded flower stems back to the first set of side flower buds for a tidier appearance and better flower show. 10. Knautia – Knautia macedonica ‘Dark Red’ (formerly Scabiosa macedonica) A close look at the flowers show why this was once grouped with the pincushion flowers (Scabiosa). The long lasting blooms are attractive to bees and the plant performs best in well-­‐
drained soils and full sun. Although short lived, this perennial is a beautiful addition to the perennial garden. 11. Salvia – Salvia spp. A favorite of many gardeners, it is commonly used in the garden and flower arrangements. Look for cultivars that do not flop open. I find regular grooming is needed to keep them looking their best. See the 2000 Plant Evaluation Notes for hardy Sages by Chicago Botanic Garden. http://www.chicagobotanic.org/downloads/planteval_notes/no14_sage.pdf 12. Jupiter’s Beard – Centranthus ruber ‘Rosenrot’ An underutilized perennial relative of garden valerian, the fragrant flowers attract bees and other insects. This short lived perennial will self seed and grows best in well-­‐drained soils and full sun. 13. Wisteria – Wisteria Northern gardeners should select American (Wisteria frutescens) and Kentucky (Wisteria macrostachys) wisterias that bloom on current season’s growth. It takes 5 to 7 years for plants to reach maturity and produce fragrant flowers. Wisteria attaches to structure with clockwise twining stems. Japanese wisteria (Wisteria floribunda) and Chinese wisteria (Wisteria sinensis) are plant hardy in zones 5 to 8 or 9, but flower buds are often killed in cold winters or late spring frosts. 14. Dutchman’s Pipe – Aristolochia macropylla An old fashioned favorite used for many years as screening on porches. The unusual pipe-­‐shaped flowers appear in May or June and are often masked by the foliage. It attaches to structure as a twining vine. 15. Arctic Beauty Kiwi – Actinidia kolomikta ‘Arctic Beauty’ This vine provides colorful foliage, fragrant flowers, small edible grape size fruit that ripens in Sept-­‐Oct and is hardy zones 4 to 8. You’ll need at least one male plant for every five female kiwis for fruit formation. Arctic Beauty is known for its colorful foliage, early ripening fruit and shade tolerance. Excess fertilization and shade reduces intensity of foliage color. Prune like grape in late winter. This attaches to structure with twining stems. 16. Japanese Hydrangea Vine – Schizophragma hydrangeoides ‘Rosea’ A four season vine that tolerates shade and provides pink flowers in summer, yellow fall color, and orange-­‐brown bark. Grow in full to part shade in zone 5 to 9. Slow to establish. 17. Golden Star – Chrysogonum virginianum ‘Pierre’ A low growing perennial that blooms spring to summer and is evergreen in mild climates. Pierre tends to be long blooming and is a 6” tall clump forming groundcover. Hardy in zones 5 thru 9. 18. Dwarf Chinese Astilbe – Astilbe chinensis ‘Pumila’ This cultivar is more heat and drought tolerant than other astilbes. The mat forming plant spreads by rhizomes making it suitable as a groundcover in partial shade. I have used in full sun (provide needed water) with success. 19. Broad-­leaf Sedge – Carex siderosticha ‘Variegata’ This beauty is great as a groundcover or edger in the shade garden. The white edged leaves look great combined with green or blue-­‐green hosta, Canadian ginger and other shade plants. Cut back old leaves in late winter and wait for the foliage to emerge (hardy zones 5 to 9). 20. Lady’s Mantle – Alchemilla mollis Check out this plant in early morning when it is covered with dew or after a rain when the beads of water glisten on the soft green foliage. The chartreuse flowers top the leaves in late spring through summer and work great in cut flower arrangements. The plant prefers cool moist summers so avoid hot dry locations or grow in partial shade. 21. English Lavender – Lavandula angustifolia Good drainage and full sun are the keys to successfully growing lavender in northern climates. Try hardy cultivars like Hidcote and Munstead to increase your success. Fragrant flowers and foliage add color, texture and a bit of aromatherapy to any garden. In early spring, prune back just above last year’s point of new growth. Northern gardeners may want to wait to see what survived winter and prune accordingly. 22. Himalayan Cinquefoil – Potentilla atrosanguinea Grow in rock gardens and allow to sprawl or en masse at the edge of planting beds. The silvery undersides of the leaves combined with the orange-­‐red flowers make this a standout in the garden. It grows best in full sun and well-­‐drained soils. 23. Heartleaf Oxeye – Telekia speciosa Combine with other bold and beautiful plants and ornamental grasses for impact in any size landscape. Grow in full sun with moist soils or part shade in well-­‐drained soils. 24. Penstemon – Penstemon spp. These plants are great for hot dry locations. Include penstemons for their foliage, flowers, seed heads (on some) and attraction to bees, butterflies and hummingbirds. 25. Rose Campion – Lychnis coronaria You can’t miss this plant in the garden. The gray foliage topped with hot pink flowers is a standout. Make sure to grow it in full sun and well-­‐drained soils. This short lived perennial will reseed to continue on in the garden for years to come. 26. Peachleaf Bellflower – Campanula persicifolia Great in a wildflower gardens, naturalized sites or en masse in a perennial gardens. Deadhead for repeat bloom. 27. Blue False Indigo – Baptisia australis Allow plenty of room for this North American native. Plants grow 3 to 4 feet tall and wide and perform best in full sun. This 2010 Perennial Plant of the Year provides a dramatic flower and foliage combination, inflated black seed pods good for dried flower arrangements and drought tolerance. Visit the Perennial Plant Association website http://www.perennialplant.org/index.asp 28. Geranium – Geranium sanguineum var. striatum Select perennial geraniums for their foliage and flower attributes. Prune back the plants after bloom if the foliage declines, spots or is otherwise unattractive. Rozanne and the slightly taller Jolly Bee are long blooming with good-­‐looking foliage throughout the season. In 2004 Chicago Botanic garden evaluated hardy geraniums. A good look at many that are still on the market though new and better performing varieties have since been introduced. 29. Combo Alert #4 Blue Hosta and Golden Hakone Grass Hosta and Hakonechloa macra ‘Aureola’ The fine texture of the colorful Hakone grass contrasts nicely with the bold leaves of hosta. Both plants tolerate shade and moist soil. Make sure the Hakone grass (2009 Perennial Plant of the Year) receives ample moisture during establishment. 30. Bugbane – Actaea racemosa (formerly Cimicifuga racemosa) Add vertical interest and color to the shade garden with this plant. The foliage looks good all season and the white flowers dance above the foliage in summer. A. ramosa (fragrant flowers) and A. simplex bloom later in the season. 31. Masterwort – Astrantia ‘Rainbow’ Grows best in part shade and well-­‐drained soils. Keep soil mulched and moist in full sun locations. Peak flowering is in late spring though many will bloom sporadically throughout the growing season. 32. Rodgersia – Rodgersia Include this shade lover for a bit of bold texture. The horse chestnut tree-­‐like leaves are a dramatic contrast to ferns and astilbes. The panicles of white or red flowers are standouts in the late spring to mid summer garden. Keep soil moist. 33. Goat’s Beard – Aruncus dioicus Give this large plant (4 to 6’ tall and wide) plenty of room in the shade garden. The male plants have showier flowers that do not reseed – unfortunately most nurseries do not separate by gender. Leaf spot can be a problem. A. ‘Kneiffi’ is 3’ tall with finely cut foliage and A. aethusifolius is 6 to 8” mound with 12” white flowers and bronze fall color. 34. Bottlebrush Buckeye – Aesculus parviflora A bold summer blooming shrub related to the Ohio, Red and Yellow buckeyes. White spires of flowers appear in summer. Plants prefer full to part sun and moist well-­‐drained soils. They can grow to 8 to 12’ tall by 8 to 15’ wide. Leaves turn a beautiful yellow in fall when grown in ideal conditions. Pear shaped fruit with glossy “Buckeye” nuts develop in Sept. and Oct. in Midwest and southern areas with longer growing seasons. 35. Angelina Sedum – Sedum repestre ‘Angelina’ An evergreen sedum that performs best in full sun or light shade and well-­‐drained to droughty soils. The intense color makes it a great accent plant, filler in containers, edger or groundcover when planted en masse. The yellow star shaped flowers appear in summer and the foliage often turns amber in fall. 36. Musclewood – Carpinus caroliniana The subtle flowers of this North American native are often overlooked. The subsequent fruit adds to the winter interest provided by the smooth gray bark. Tolerant of heavy shade this small scale tree can be used in both small and large landscapes. Look for newer introductions like Johnson Nursery Strain, Ball ‘O Fire and Firespire selected for their growth habit and/or outstanding fall color. * Vista of Rock Garden – One of Boerner Botanical Gardens strength is the age of the garden and major plantings, diverse ecosystems and the vistas. The gardens are designed as intimate rooms with several vistas, like this, designed to overlook a variety of ponds and lagoons throughout Whitnall Park. 37. Red Fox Veronica – Veronica spicata ‘Red Fox’ Look for speedwells that do not open in the center and repeat bloom throughout the season. Red Fox is a good red variety. Royal Candles and Sunny Border Blue are two blue cultivars to consider. 38. Allegheny Spurge – Pachysandra procumbens This native has a more informal look than Japanese pachysandra (Pachysandra terminalis). The foliage is somewhat evergreen and I find the plants are easier to use in small clusters and blend with other shade tolerant plants than the glossy leafed Japanese pachysandra. 39. Japanese Painted Fern – Athyrium nipponicum ‘Pictum’ This is the 2004 Perennial Plant of the Year. The colorful stems and variegated foliage brighten the shade. Remove solid green sprouts that can spontaneously appear in plantings. Though a nice contrast the green plants will take over the variegated portion of the planting. 40. Golden Moneywort – Lysimachia nummularia ‘Aurea’ Avoid using this assertive plant in landscapes near natural riparian forests. This ground hugging groundcover is great as a lower level groundcover. The chartreuse/lime green leaves provide a nice backdrop to the darker green foliage of hostas, Canadian ginger and other shade tolerant plants. For photos and more details on these and other plants visit Ask Melinda and Plant Guide at www.melindamyers.com