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The Best Reblooming Clematis

When visiting older established gardens, if there is a border garden, it will probably contain at least one of these three plants: peony, bearded iris, and clematis. These are often considered old-fashioned plants because they have been regularly planted in gardens for so many years. All three of these plants are generally considered reliable spring bloomers and once blooming. The bloom period can be over several weeks, and there are usually early and late-season varieties, but their flowering time is usually spring and early summer with additional flowers not expected until the next spring. There are, however, exceptions.

Over the past several years, there has been a resurgence of interest to select those that will rebloom. This is especially true with clematis, and with a little effort, a gardener can have plants that will rebloom once and sometimes even twice. I recently discussed reblooming clematis with Linda Beutler, curator of the Rogerson Clematis Collection in Lake Oswego, Oregon, and here are some of her thoughts.

The fully double ‘Duchess of Edinburgh’ can bloom as many as three times in a season. Image from the Friends of Rogerson Clematis Collection archive)

Reblooming Clematis Care

Most clematis grow best in the full to partial sun and like to have their roots shaded and their tops in the sun. After a clematis has flowered, deadhead it, (remove old flowers) and do some light pruning if necessary. Deadheading prevents the plant from setting seed and light pruning removes any dead stems and opens the plant up to more sunlight. Fertilize the plant at this time. Linda said a rose & flower fertilizer is generally good. At the Rogerson Clematis Collection, they use a fertilizer with an NPK, (Nitrogen- Phosphorus-Potassium nutrient numbers on the bag or box) ratio with numbers under 10. Currently, they use a 5-7-2. Often, 30-45 days after fertilization, the plant will re-bloom. For a full list of care tips, visit the Rogerson Clematis Collection page on clematis care (click here).

Five Recommended Reblooming Clematis

‘Blue Ravine’ is a large-flowered rebloomer. (Image from the Friends of Rogerson Clematis Collection archive)

Naturally, some plants will consistently rebloom easier, and for that consistent rebloom the following are five clematis varieties that Linda recommends.

  1. Clematis alpina ‘Pamela Jackman’ (Zones 3-9) flowers first in April and reblooms well, often in late summer. It requires trellising and can also be grown well in a container. With this clematis, you can have April in August.
  2. Clematis ‘Elegant Rhythm’ (Zones 5-9) is a handsome herbaceous perennial clematis named and introduced by Joy Creek Nursery. If you do not allow it to set seed, it will rebloom through late spring and summer, just like annual Scabiosa or perennial Astrantia.
  3. Clematis ‘Duchess of Edinburgh’ (Zones 4-9) is a double that can bloom as many as three times in a long growing season. Deadhead the spent blooms and fertilize with most any fertilizer for roses. The fully-double flowering clematis will often produce flowers that are less doubled when they rebloom.
  4. Clematis ‘Blue Ravine’ (Zones 4-9) is an excellent large-flowered variety and has the added advantage of flowering well—if paler—in partial shade. The photo above was taken in September 2020 and looks as though it were in spring.
  5. Clematis ‘Niobe’ (Zones 4-9) is a deep-red variety (pictured below reblooming in the autumn). Look closely at the image and you can see this clematis is growing through and is supported by another plant. This particular support plant is Osmanthus heterophyllus ‘Goshiki’.
The deepest-red-flowered ‘Niobe’ is growing up an Osmanthus shrub. (Image from the Friends of Rogerson Clematis Collection archive)

Clematis are often grown in this way using another plant for support. Often some of the old garden roses are used because they not only offer a good support system, but the clematis will flower again when the once-blooming roses are finished.

If you are visiting the Pacific Northwest, and have any interest in clematis, be sure to visit the Rogerson Clematis Garden, which is part of the Lake Oswego, Oregon, Parks & Recreation system. With over 900 taxa represented, it is the most comprehensive collection of clematis within a public garden in North America. Admission is free.

The handsome clematis ‘Elegant Rhythm’ has pendulous flowers. (Image from the Friends of Rogerson Clematis Collection archive)

Outstanding Cannas

Every summer I plant my favorite Canna standby, ‘Striata’. It is the perfect floral backdrop for other bright garden flowers. (Image by Jessie Keith)

Cannas are summer-garden workhorses. They grow lushly in the hottest months, only requiring regular water, partial sun, and maybe a hit of slow-release fertilizer at the beginning of the season. Their leaves are bold and lovely, their tropical flowers come in lots of warm pretty colors, and hummingbirds are prized pollinators. The plants also spread and are easily divided and shared. My garden will never be without one.

Canna Origins

Hummingbirds love visiting all canna blooms!

Cannas (Canna hybrids, Zones 8-11) are subtropical to tropical and American. There are 12-21 accepted species, depending on who you reference. These are found in Mexico, Central America, the Caribbean, and tropical South America. The common garden type is Canna × generalis, a hybrid of several species. They were cultivated by native Americans, presumably for both their attractive flowers and fleshy, edible roots. In the late 1900s, cannas were popularized in European and then North American gardens. Since this time, many attractive hybrids have been developed, with new varieties appearing now and then.

Ten Favorite Cannas

Red-flowered cannas, like ‘Kreta’, are sure to attract hummingbirds.

Alaska‘ (3-4 feet): Large cream-colored blooms are the great beauty of this compact canna, and its blue-green foliage is also respectably pretty. It gets all-around rave reviews.

Australia‘(4-5 feet): Large red flowers and big bronzy-purple leaves make this impressive canna a standout. If you are looking to fill a large space with lots of reliable color, this is your canna. It contrasts well with orange- and yellow-flowered plants.

‘Alaska’ is a compact, cream-colored canna.

Cleopatra‘ (4-5 feet): Expect explosive fireworks of color with ‘Cleopatra’. Its impressive green leaves have irregular blocks of dark purple. These are in stark contrast to its flowers, which are half red and half yellow with red spots. Expect it to receive many compliments.

Kreta‘ (3-4 feet): Here is a great canna for nonstop flowers. Its numerous red blooms are prolific and attract lots of hummingbirds and rise above large green leaves.

Musifolia‘ (6-8 feet): This old canna variety is grown for its tall stature and impressive large leaves with hints of red and purple. In the height of summer, it will also offer spikes of small red flowers.

Phasion‘ (syn. ‘Durban’ and ‘Tropicanna’, 3-4 feet): Most regard this as the most electrifying of all cannas. Few garden plants can challenge its impressive tropical palette of colors. Its striped leaves alone are a masterpiece, and its brilliant tangerine-orange flowers add the winning touch.

Striata‘ (syn. ‘Praetoria’, ‘Bengal Tiger’, and ‘Aureostriata’, 5-6 feet): My garden is never without a ‘Striata’ for summer color. Its pale-yellow striped leaves provide a more neutral backdrop for the light orange flowers it produces from midsummer to frost in my area.

Toucan® Coral is a beautiful compact canna from Proven Winners®. (Image thanks to Proven Winners®)

Tenerife‘ (3-4 feet ): Big golden flowers speckled with deep orange-red make this an extra lovely compact canna. Its leaves are medium green.

Wyoming‘ (3-4 feet): I always confuse ‘Wyoming’ and ‘Australia’ because they are comparable in every way except flower color. This one has beautiful orange flowers to offset its purplish-bronze foliage.

Toucan® Series (Scarlet, Yellow, Dark Orange, Coral, 2.5-4 feet): Toucan cannas are big bloomers on short-statured plants. They come highly recommended for containers. Expect them to perform beautifully all summer long.

Canna Care

Canna rhizomes are easy to plant, dig, and divide.

Cannas are lush, tropical to subtropical perennials that grow best in the full to partial sun. They thrive in rich moist to average soils–the addition of organic matter at planting time is recommended. Black Gold Garden Soil is a great choice. Provide a boost of continuous-release fertilizer formulated to encourage good growth and flowering. They originate in warm, humid, rainy areas and appreciate regular water. Many even grow well along pond margins or boggy spots. When conditions are warm, they will flower. If they are not hardy where you live, dig their dense, fleshy rhizomes in the fall and store them in a cool, dark place through winter. Plant them again outdoors when the soil has warmed and frosts are gone.

Canna Yellow Streak Virus

Several viral diseases will put a damper on canna growth and flowering. The two most common are the canna yellow streak virus (CaYSV) and the canna yellow mottle virus (CaYMV). Infected plants show abnormal leaves with browning or yellowing streaks or mottled patterns. If your canna leaves exhibit these, dig and dispose of them immediately. When replacing them, buy only certified virus-free stock (specialty growers are usually the most reliable source). Be sure not to reuse the potting soil, if your diseased plants were in containers.

Native Spring Flowering Trees For Bees

When flowering trees bloom, they are a boon for pollinators, particularly bees of all sorts. They bloom en masse for a week or more, offering a lot of essential food with little forage. There are no better plants to boost these essential pollinators in the garden, and the native trees here feed for both our honeybee friends as well as native bees.

Spring Flowering Trees For Bees

The trees in this collection vary in size from small to large. All are beautiful in their own right, and most grow and flower best when grown in the full sun. Soil and moisture requirements vary. If any of these trees interest you, I recommend reading this article about how to site and plant a new tree, by Russell Stafford.

Red maple flowers give the trees a reddish caste in the spring. (Image by Famartin)

Most do not realize that the early spring flowers of red maple (Acer rubra, Zones 3-9, 40-70 feet) are essential early food for honeybees and native bees (Red Maple (Acer rubrum L.), an Important Early Spring Food Resource for Honey Bees and Other Insects, 1985). Their small masses of red flowers appear before the leaves emerge in late winter or early spring and provide winter-weary bees needed pollen and nectar. The lovely eastern-native shade trees cool and beautify large landscapes all summer long, and their leaves turn shades of red, orange, and yellow in the fall. They grow well in open, sunny areas in dry uplands as well as moist lowlands.

The new leaves of downy serviceberry are covered with down and emerge after the white flowers that attract bees. (Image by Dcrjsr)

The delicate white flower clusters of the eastern North American downy serviceberry (Amelanchier arborea, Zones 4-9, 15-30 feet) also provide early-spring food for lots of bees, especially small native bees (mostly mining bees and sweat bees). Its new leaves emerge after the flowers and have downy hairs on them, which explains the common name. In summer, the edible summer fruits are a favorite of many fruit-eating birds, and the fall leaves turn brilliant shades of orange, red, and yellow. Some gardeners like to collect the ripe serviceberries for fresh eating, jam making, or pies. Though the multi-stemmed tree grows well in forests, it develops its finest habit, fruits, and flowers when grown in the full sun.

Redbuds are extra lovely trees for bees.

Eastern redbuds (Cercis canadensis, Zones 4-8, 20-30 feet) bloom for one to two weeks in the mid-spring with bare branches laden with lots of tiny, purplish-pink, pea-like blooms that glisten in the sun. Bees can’t get enough of them. Once the flowers of these eastern North American natives cease, the large, heart-shaped leaves unfurl. Sometimes they are reddish or purple as they emerge. Lots of small, thin pods follow the flowers, which turn from green to papery brown before they split open and release their seeds. The fall leaves turn humdrum shades of yellow. The fast-growing trees tolerate partial shade but perform best in the full sun and fertile to average soil. There are lots of great specialty redbud varieties from which to choose with variously colored leaves and flowers.

The fragrant, white flowers of fringetree draw many bees.

A native of the southeastern United States, white fringetree (Chionanthus virginicus, Zones 3-9, 12-20 feet) has fine, fringed, white flowers that are fragrant and almost exclusively bee-pollinated. They bloom for several weeks in May and June. Fleshy fruits that turn from green to blue-black follow, which feed many bird species. The small trees develop a pleasing rounded canopy and have green lance-shaped leaves. Expect the leaves to turn yellow in the fall.

Newer green hawthorn varieties lack the thorns of the wild trees. (Image by David Stang)

Green hawthorn (Crataegus viridis, Zones 4-8, 20-35 feet) is a handsome small tree from the eastern United States whose copious clusters of white mid-spring flowers attract lots of bees. In the fall, the glossy green, toothed leaves turn attractive red and purple hues, which look striking against the bright red fruits that cover the branches and are retained into winter for birds to eat. The branches of wild specimens have thorns, but some varieties, such as the popular ‘Winter King‘ have few thorns, while also offering more flowers and brilliant-red fall fruits. The newer variety Crusader® is equally beautiful and totally thorn-free.

The attractive nectar guides of catalpa flowers are like beacons to bees.

The large, lush, copious flower clusters of the northern catalpa (Catalpa bignonioides, Zones 4-8, 40-60 feet) bloom in the late spring. The fragrant flowers have maroon and yellow nectar guides designed just for bee pollination, so the insects know where to land and gather nectar and pollen. Large, elongated pods follow the flowers. Its large, elongated/oval leaves turn yellow shades in the fall. The only downside of these easy-to-cultivated trees is that their fruits are messy, and the trees live for only around 60 years. Still, they have high wildlife value and beauty. If you have a spacious yard, plant them where they can be enjoyed but won’t be a bother. These trees naturally exist across the southeastern United States and tolerate average to moist soils.

The large, flattened flower clusters of nannyberry attract many insect pollinators. (Image thanks to USDA-NRCS)

It’s always nice to add a real pollinator generalist and Nannyberry (Viburnum lentago, Zones 2-8, 18-25 feet) is a very good one. It is a small tree, unlike most other viburnum species, which are shrubs.  Its flattened clusters of ivory flowers appear in mid to late spring, and they are pollinated by bees as well as other insects. The caterpillars of the spring azure butterfly feed on the summer leaves. Edible black fruits and bright red or orange leaves comprise its fall show. Birds eat the nannyberries and disperse the seeds, but the sweet fruits are also edible to humans as well as other wildlife. Nannyberry tolerates moist soils or those with average drainage.

Favorite Flowering Ground Covers

‘Shell’Pink’ and ‘Orchid Frost’ lamiums look lovely side-by-side.

If you have a garden area that needs filling in, whether along a slope, between plants, or beside stone steps or rocky retaining walls, there are many beautiful perennial groundcovers for the job. They range from ones that do well in hot, dry areas to others that like moist shade.  I have chosen groundcovers that have beautiful leaves as well as flowers, which do not overwhelm surrounding plants and are easy to grow.

Flowering Groundcovers for Full to Partial Shade

‘Orchid Frost’ is one of many pretty deadnettles for shady gardens.

Spotted Deadnettle (Lamium maculatum, Zones 3-8): One of my favorites for shade is named spotted deadnettle, or simply deadnettle, even though it has no prickly nettles.  I have had several varieties in my shade garden for years. The early summer flower stalks are about 7 inches tall, rising over 4-inch-tall plants that spread several feet across. There are lots of varieties with variously spotted leaves and blooms of purple, pink, or white that are visited by bees. My favorite varieties include ‘Orchid Frost’ with lavender flowers and beautiful silver leaves, ‘Aureum‘ with bright pink flowers and white-striped gold leaves, Shell Pink‘ with palest pink blooms, and ‘White Nancy’, which has white flowers and silvery leaves. Lamium is deer-resistant, spreads gently, and is easily divided and transplanted. Plant it along shaded bed edges or allow it to cascade from the side of a shaded container garden. Lamium likes full to partial shade, and moist, well-drained soil.

Fragrant sweet woodruff flowers and plants look attractive in shaded gardens.

Sweet Woodruff (Galium odoratum, Zones 4-8): Another partial- to full-shade groundcover is European sweet woodruff, which also has the benefit of being an herbal plant used to flavor May wine in Europe. It has clusters of starry white flowers in the spring and whorled, star-shaped leaves; both are fragrant, but it’s the flowers that are used to flavor the wine. (Click here for a May wine recipe.) Sweet woodruff is about 8 inches tall and gently spreads around trees and shrubs.  It likes moist, well-drained soil and is deer resistant!

Wild ginger creates mats of attractive foliage through the growing season.

Wild Gingers (Asarum spp., Zones vary): There are many wild gingers with lovely ground-covering foliage and interesting beetle-pollinated spring flowers. The popular native species is Canadian wild ginger (Asarum canadensis, Zones 2-8). Its medium-green, heart-shaped leaves look very pretty on bed edges or to hold shaded garden banks. Chinese wild ginger (Asarum splendens, Zones 6-8) is more ornamental with its pointed, green leaves that have spectacular silver markings.  ‘Quick Silver‘ is the best variety. Small, three-petaled, purple flowers appear around the base of the plants in spring. It also does well in full to part shade.  Most Asarum reach 6 to 8 inches, like average well-drained soil, and are deer resistant.

‘Cutting Edge’ Tiarella has attractive spring flowers and lovely leaves. (Image thanks to Proven Winners)

Foamflower (Tiarella spp.): These pretty native perennials have attractive, lobed foliage and spires of foamy flowers that appear in late spring. The flowers may be ivory or pink and attract both bees and butterflies. The pretty clumps of ornate leaves spread over time. Try the new Proven Winners variety ‘Cutting Edge’, which has spectacular green, maple-shaped leaves with red venation. Provide foamflower with full to part shade, and moist, well-drained soil amended with fertile organic matter, such as Black Gold Natural & Organic Garden Compost Blend. In fact, this amendment will create a good soil foundation for all of the shade-loving groundcovers mentioned.

Flowering Groundcovers for Full to Partial Sun

Creeping thyme doubles as an herb and groundcover.

Creeping Speedwell (Veronica prostata, Zones 4-8): Grow this creeping groundcover along a border edge or in a rock garden. The stunning variety, ‘Aztec Gold’, has gold leaves with violet-blue flowers in the early summer.  It reaches 6 inches tall, is heat tolerant, and needs moderate moisture. Deer don’t like it but bees and butterflies do.

Creeping Thyme (Thymus serpyllum, Zones 4-8): This easy garden herb is one of my favorites. It does well between paving stones or cascading down rock walls. The fragrant leaves are tiny plants reach 2-inches-high. The spreading mats have little summer flowers of purple, bright pink, or lavender, depending on the variety you buy. Bees love the blooms! Check out ‘Elfin’ with purple flowers, ‘Annie Hall’ with pink flowers, and ‘Silver Posie’, which has white-edged leaves and lavender flowers. The fragrant leaves can be used in cooking. Thyme needs full sun, very well-drained soil, and is drought-tolerant once established. Like most plants in the mint family, it is also deer resistant.

Creeping phlox is perfect for garden edges and slopes (‘Emerald Blue’ is at the far left, and ‘Candy Stripe’ is at the far right)

Stonecrop (Sedum spp., Zones vary): For hot, dry, sunny, areas nothing can beat, low-spreading stonecrops.  Many have beautiful, succulent leaves, as well as starry flowers that attract bees and butterflies. It is very easy to pull up a piece and replant it to help fill in an area quickly. Some good varieties are the 2-3 inches tall ‘John Creech’ (Sedum spurium ‘John Creech, Zones 3-9) with pink, summer flowers, SunSparkler® Wildfire (Zones 4-9) that has red leaves edged in rose as well as pink flowers in the late-summer, and ‘White Diamond’ (Sedum pachyclados ‘White Diamond’, Zones 5-9) with blue-green rose-shaped leaves and white summer flowers.  The broad-spreading ‘Angelina’ (Sedum rupestre ‘Angelina’, Zones 5-9) is a popular variety with gold spiky foliage and yellow summer blooms.  Sedums are drought-tolerant once established.

Creeping Phlox (Phlox subulata, Zones 3-9): This has some of the most beautiful flowers of all the groundcovers and blooms for up to 4 weeks in the spring.  It averages 5 inches tall and spreads quickly. Plant creeping phlox in open, sunny areas along slopes or retaining walls, in front of shrubs, or in rock gardens where they will get full sun and well-drained soil.  Look for the colorful varieties ‘Scarlet Flame’ with red-eyed rose-pink flowers, ‘Emerald Blue’ with pale lilac-blue flowers, and ‘Candy Stripe’, which has pink flowers edged in white.  Creeping phlox is deer resistant.

Snow-in-Summer can take heat and drought!

Snow-in-Summer (Cerastium tomentosum, Zones 3-7): gardeners with hot, dry, sunny spots that need a flowering groundcover should grow snow-in-summer. It creates a broad, spreading mat of silver leaves that erupt with cascades of white flowers in the summer. Try the more compact variety, ‘Yo Yo‘. It is beautiful! Site it as you would creeping phlox. Bees and butterflies love the flowers!

These easy groundcovers will help to provide needed in sweeps across your garden. Buy a few to fill in bare areas, and you will be glad you did.

Groundcovers to Avoid

It is important to note that there are some popular groundcovers to avoid because they are invasive and have become an ecological problem in wild areas. These include groundcover periwinkle (Vinca minor and Vinca major), wintercreeper (Euonymus fortunei), Bugleweed (Ajuga reptans), Japanese spurge (Pachysandra procumbens), and worst of all, English Ivy (Hedera helix). English ivy is a tree-killer in zone 7 or warmer (click here to learn more). The evergreen types are truly the worst because they smother native spring ephemerals and other natives along the forest floor. Avoid planting them, if you can.

Native Violets For The Garden

Halberd-leaf yellow violet (top right), Canadian violet (bottom right), Labrador violet (bottom left), and bird’s foot violet (top left)

Last spring I visited the Smokey Mountain National Park during high wildflower season, and I was struck by all of the unusual, beautiful native violets there.  All had a delicate beauty suited to woodland and shade gardens. I started looking for garden center availability and was struck by the many North American violets available to native gardeners. Most are perennial, but a few survive as spring annuals.

Violets and Wildlife

‘Freckles’ is an uncommonly beautiful common violet. (Image thanks to Baker Creek Heirloom Seeds)

Overall, our native violets are easy, pretty, and have a place in the garden. In fact, they support wildlife more than most might think. Even the native common blue violet (Viola sororia, Zones 3-9), which gardeners often weed from their beds and lawns, are beautiful and feed the larvae of many species of fritillary butterflies, which are close relatives of monarchs. According to the Xerces Society, a whopping 14 species of greater fritillaries (Speyeria spp.) and 16 species of lesser fritillaries (Bolloria spp.) lay eggs on common violet leaves for their caterpillars to feed upon, develop, and grow.  The fragrant flowers, which have bee nectar guides and are largely pollinated by native bees, are also visited by butterflies. Some native bees are even specialized for Viola flower pollination, such as the violet miner bee (Andrena violae).

Most fritillaries are orange and black. Different species have different pattern markings and ranges.

For these reasons, they are worth leaving alone in lawn areas or other places in the yard. Let them sow and spread freely where they do not compete with other garden plants. If you don’t have common violets in your yard, a good garden variety to try is the beautifully speckled ‘Freckles‘. My mother started it from seed over 25 years ago, and they are still beautiful in the garden! The flowers look very pretty clustered in small bud vases.

Six Beautiful Native Violets for the Garden

Most native violets grow best in fertile, moist soil and partial sun to shade. They also tend to spread, some slowly and others more quickly. They make fine garden perennials, especially for more naturalistic beds. Any exceptions to these rules are noted.

My favorite native violet is the bird’s foot violet, which has large 1.5-inch flowers and fine foliage.

When researching these native violets, I quickly found that all native American violets feed numerous native bees and play larval host to many fritillary species–too many to be mentioned by name. Lots of American fritillaries are threatened or endangered, so maintaining a few native violets in your yard is important! It is also important to source nursery-grown stock or seeds rather than plants collected from the wild. (Click here to learn more about avoiding poached, rare plants.) All seed and plant sources provided here are legitimate.

Labrador violet is often evergreen to semi-evergreen and has purplish-bronze foliage.

Canadian violet (Viola canadensis, Zones 2-8): These hardy perennial violets can reach up to 12 inches and produce lots of white or pale-violet spring flowers that stand tall above the large, heart-shaped leaves. It makes a pleasing native groundcover for moist woodland or shade gardens and is native across much of central and northern North America, extending far into Canada. Expect Canadian violet to self-sow and spread naturally to create a seasonal native groundcover for the shade.

Halberd-leaf yellow violet (Viola hastata, Zones 5-8): Though rarely sold in commerce, at all but the most select native plants sales hosted by native plant societies, Halberd-leaf yellow violet is one of the prettiest of all native woodland violets. Its attractive leaves have silvery markings and sunny yellow flowers are produced in the spring. The woodland native is found in old woods across the eastern coastal United States. If you can find it, grow the 4-8-inch plants in a moist, shaded garden spot.

American dog violet (Viola labradorica, Zones 2-8): Just look at that hardiness zone! This little 3-6-inch violet has native populations that extend into the farthest north reaches of eastern Canada, and it is so lovely. Its low-growing bunches have purplish-bronze, heart-shaped leaves as well as royal-violet-purple flowers in the spring and summer. It is evergreen to semi-evergreen, making it an excellent small-scale groundcover violet for the full sun to partial shade.

Smooth yellow violet is a sweet little yellow-flowered species for shaded gardens.

Bird’s foot violet (Viola pedata, Zones 4-8): I love this unique violet for its fine foliage, which resembles little green bird’s feet, and wide, violet-blue flowers punctuated by orange eyes. They are found in old, established sandy woodlands across eastern North America. Expect the 1.5-inch flowers to appear from spring to midsummer. They will tolerate full to partial sun. Well-drained soil and regular moisture are required. The 3-10-inch plants do not tend to spread.

Prairie violet (Viola pedatifida, Zones 3-7): The sun-loving little prairie violet is native across the prairie lands of Central North America and spreads less aggressively than average violets. Its bright violet-purple flowers look pretty against the delicate, cut-leaf foliage. Unlike most violets, prairie violet will tolerate drier soils. Flowering occurs from mid-spring to early summer. Sometimes it will rebloom later in the season. Plant the 6-inch violets along garden edges where they can slowly self-sow.

Smooth yellow violet (Viola pubescens var. eriocarpa, Zones 3-7): Here is a pretty yellow-flowered violet that grows best in shaded, moist, eastern North American woodlands and gently spreads. Expect it to produce little yellow blooms from mid-spring to summer. Standard Viola pubescens has downy rather than smooth leaves.

Starting Native Violets From Seed

Violet seeds are easily collected or available for sale.

These perennial violets are most often sold from seed, so they are not expensive to grow. Most take a year before flowering from seed. We recommend sowing the seeds in flats of quality potting mix, such as Black Gold Natural & Organic Potting Mix, outdoors in the fall. This method, called moist outdoor seed stratification (click here for stratification guidelines), lets them experience the winter moisture and cold, which many violet seeds need to germinate. When grown by this method, they often sprout in the late winter or spring.

Other Violet Uses

Violets serve other useful purposes in the garden. The flowers are edible, and their fragrant blooms have been used to make perfume over the ages. One common old-fashioned use for the flowers was to candy them. The sugar-crusted violets hold their color, are tasty, and look beautiful for decorating cakes and cookies. (Click here for a good candied-violet recipe.) The flowers can also be used to make a delectable, violet-blue simple syrup that can be added to mixed drinks and lemonade. (Click here for a good violet simple syrup recipe.)

If you have lots of common violets in the yard, try making candied violets.

Favorite Old & New Salvias For Flower Gardens

The red and white ‘Hot Lips’ is heat-tolerant and beautiful.

It would be difficult to come up with a group of plants that can add as much to the garden, in so many ways, as the flowering sages in the genus Salvia. Their colorful, two-lipped blooms are lovely and the many garden representatives have diverse growth habits, flower colors, fragrance (usually in the leaves), as well as being long-blooming and low-maintenance.

In addition to the above-mentioned attributes, salvias are excellent plants for a pollinator garden–attractive to bees, butterflies, and hummingbirds–and most are summer bloomers that love sunny garden spots. In my garden, the flowers are hummingbird magnets. It is delightful watching the territorial antics of these amazing birds.

Of the more than 900 species of these mints (Look for the square stems!) distributed throughout the temperate and tropical zones of the world, only several species are commonly cultivated in the garden. With so many types of salvia across the world, it stands to reason that there is lots of variation among the species and their hardiness. While many are technically perennial and perform exceptionally well in my Pacific Northwest summers, they may not survive a winter. Poor drainage can be a factor for winter survival, so I add additional perlite for increased drainage when planting them. Gran-i-Grit and coarse sand can also improve the drainage of raised gardens to enhance salvia survival.

Great Garden Salvias

‘Amistad’ has glorious purple flowers that hummingbirds love.

For me, salvias were a late addition to the plant palette in my garden, however, once I started growing them, it was as though I could not stop. I re-planted favorites each spring and always add some new varieties that I have not grown before. I discovered they were wonderful container plants, and now we always have salvias in pots on our deck. From my own experience, I have discovered what I would consider outstanding performers. Below is a listing of some of my favorites.

Introduced nearly 20 years ago, Black & Blue sage (Salvia guaranitica ‘Black & Blue’, Zones 7-10) was one of the first ones in my garden. It was recommended by the owner of a local garden center, and this salvia has become such a favorite that I plant it every year. The 4-foot plant has deep blue flowers with black calyces, hence the name ‘Black & Blue’.  Amistad salvia (Salvia guaranitica ‘Amistad’, Zones 7-10) is another good performer with deep purple flowers. It has a more compact growth habit than ‘Black & Blue’ with a final height under 3 feet. Both are excellent hummingbird attractants and will bloom all summer. They are also technically hardy to my area but very sensitive to winter moisture.

Black & Blue sage looks the part with its bicolored flowers.

Proven Winners has recently released a series of salvias in the Rockin series. I have grown several in this series, and they are excellent. My favorite is Rockin® Fuchsia (Zones 9-11) and as the name implies, the flowers are brilliant fuchsia. It is an excellent salvia for a container in a location where bright color is desired. It is also a heavy bloomer and hummingbirds love it. Another in this series that I have grown and liked is Blue Suede Shoes (Zones 9-11), which has light blue flowers with black calyces.

Rockin® Fuchsia is a very heavy summer bloomer.

For fragrance, I have not grown any better than Cleveland sage (Salvia clevelandii, Zones 8-11). This southern California native has the most aromatic leaves of almost any plant that I have grown. It has a mounding growth habit with wrinkly, leather-textured leaves. The flowers are in rounded clusters and may be lavender to purple. Plant this where people can walk by and rub or touch a leaf.

Cleveland sage is a California native with an enticing scent.

Classic garden salvia that has distinct bi-color flowers is Hot Lips littleleaf sage (Salvia microphylla ‘Hot Lips’, Zones 7-10). The flowers are white at the base and bright red on the petals. A grouping of these in bloom makes a very striking summer display that hummingbirds cannot resist.

The flowers of ‘Hot Lips’ appear all summer.

Garden centers are continually increasing their salvia choices for customers. It was not many years ago when the selection was perhaps two to three different kinds, but today that is not the case. If you are new to growing salvias, check with other gardeners to discover what varieties perform best in your particular area. The salvias that I have mentioned are sun-loving, but there are some varieties that require at least partial shade. Others are very reliable hardy perennials.

Try some salvia plants in your garden this season. I think you will become hooked on them just as I am.

Putting Perennials To Bed In The Fall

Depending on where you live in the country, September, October, and November are the main months for putting garden beds to rest.  You may still have some warm days in these months, but once the nights and then days become chilly, it’s time to get to work. And, if you do it right, it is quite a bit of work, but more work now means less work later. Spring will be a breeze!

1. Weed

Pull as many weeds as you can in the fall to make spring gardening easier.

I have just started on the first step, which is getting all the weeds out, and it is going to take me quite a while.  Some seasons, I stay on top of weeding, and other times other priorities get in the way. This past summer was busy, so the weeds had a “field day.” It is especially important to clear weeds from right around the base of each garden plant. When weeding, it is wise to choose good tools for the job. Luckily, we have an excellent article written by my daughter, Jessie, that details the best weeding techniques, times, and tools for the job. Read it and weed! (Click here to learn how to week like a pro.)

2. Mulch

A moderate layer of mulch will protect against winter weeds, and protect perennials from the cold.

This brings us to step two, putting down fresh triple-shredded bark mulch, my preferred garden mulch, which I purchase in bulk by the yard or occasionally by the bag when only a small amount is needed. (Click here to learn about different mulch options.) Not only will mulch stop weeds, but it will also keep the soil moist, and protect your plants from big temperature swings. In addition, mulch breaks down over time, adding organic matter to the soil. Areas I have mulched for years have slowly turned into rich garden soil.  Put down around 3 inches of mulch, being careful not to cover the plant. (Not sure how much mulch to get? Click here for guidelines to calculate how much your garden will need.)

There are four rules to mulch application, particularly when it comes to mulching around plants: 1) leaf space around plants, 2) don’t mulch too thickly, 3) don’t apply mulch against the trunks of trees or shrubs, and 4) apply mulch when the soil is moist to make post-application irrigation easier. Leave a  3- to 4-inch gap between the base of the plant and the mulch, to avoid smothering the plant and causing crown rot. This is especially true of evergreen perennials and perennials with surface rhizomes, like bearded iris (Iris germanica hybrids). Peonies are also sensitive to excess mulch. One year, I mulched my peonies thoroughly in the fall and was so pleased with myself for getting it done early, but the following spring two of my prize peonies did not show up.  I had mulched too thickly and killed them. Also, do not mulch low, spreading, evergreen to semi-evergreen perennials, including Heuchera, Dianthus, ground cover sedums, such as ‘Angelina’. Mulching them commonly causes crown rot and death.

3. Cut Back Perennials

When frost takes your perennials, such as these hostas, it is time to cut them back. Semi-evergreen lamium (foreground) should be left alone until spring.

Wait until the frost has killed the leaves of herbaceous perennials before cutting them back and removing the old stalks and leaves.  This is especially important with hostas, one of my favorite perennials (I have hundreds!).  Unlike other perennials, if the leaves are removed while green, the plant will put up next year’s growth prematurely, and the following spring will have just a few scrawny leaves, so cut back hostas to 2-3 inches after the frost has taken them.

Evergreen perennials, such as Lenten rose (Helleborus spp.), myrtle euphorbia (Euphorbia myrsinites), and candytuft (Iberis sempervirens), can be left alone until spring, and semi-evergreen perennials, like coral bells (Heuchera spp.), dead nettle (Lamium maculatum), and certain daylilies, can also be left to trim back until the spring.

Some plants that add winter beauty to the garden should also be left alone.  Ornamental grasses, with pretty seed heads, gently wave in the wind, coneflowers (Echinacea spp.), black-eyed Susans (Rudbeckia spp.), and perennial sunflowers (Helianthus spp.) set seeds that songbirds like to eat in winter, so I leave them alone until the spring. Fall bloomers, such as chrysanthemums and asters, can also be trimmed in the spring. The protective stems of chrysanthemums sometimes help the tender perennials overwinter, which is nice if you like to keep them from year to year.

Another tip is to meticulously cut back perennials that are highly susceptible to leaf fungal diseases, particularly bee balm (Monarda spp.) and tall garden phlox (Phlox paniculata). Cut them back low, thoroughly, and be sure to completely remove the old leaves from the surrounding area. They should not enter the compost pile. Certain diseases can persist in the soil, even composted soil.

4. Divide and Plant

Divide large perennial clumps and spread them around in the garden to add more summer flower color where needed.

Mid-fall is the best time to divide and move hardy perennials, such as hostas, daylilies, monarda, rudbeckia, and coneflowers. If you live in USDA Hardiness Zones 3-5, or colder, divide and replant perennials earlier in the season, and only move those that are reliably hardy in your zone.  If you live in warmer zones, then you have a little more flexibility time-wise.

When dividing perennials, I typically use a sharp spade to neatly cut away a section of the plant. It is essential that each chunk has a nice portion of the crown with lots of buds on the top and roots beneath. Then I move and plant them in locations that have the right site conditions and need the color. Some falls are dry where I live in Indiana, so I am sure to irrigate my new divisions well when the weather does not bring rain. Adding Black Gold Garden Soil to the bottom of each hole adds needed fertility and a boost of fertilizer, which all plants appreciate.

So, I must get going to finish my fall garden cleanup, while the going is good (and so should you)! Then, I can spend the winter focusing on next year’s garden, worry-free.

How Do You Keep Bigleaf Hydrangea Flowers Blue?

“What’s the best way to ensure that my blue [bigleaf] hydrangea stays blue?” Question from Gaye of Saint Peters, Missouri

Answer: It all has to do with soil pH. There are two hydrangeas that have flowers whose color changes depending on whether the soil is acidic (3.5-6.8), alkaline (7.2-10), or neutral ( around 7). These are bigleaf hydrangeas (Hydrangea macrophylla, Zones 5-11) and Japanese mountain hydrangeas (Hydrangea serrata, Zones 6-9). If your flowers are on the pinker side then your soil is more alkaline, and if they are erring towards purple then your soil is more neutral. To achieve flowers with a bluer hue, you will need to lower your soil pH. There are several ways to do this.

Steps For Acidifying Soil

Black Gold Peat Moss is naturally acid, so you can amend the soil around your hydrangeas with peat to lower the pH. Follow up by adding an acidifying fertilizer supplement. Many reputable fertilizer companies make “acidifying fertilizers” or soil acidifiers–any would do. (Please click here for more information about how to acidify your soil from Oregon State University.)

Just lower your soil a little below neutral, and those hydrangeas will begin to turn blue!

Happy gardening,

Jessie Keith

Black Gold Horticulturist

What Are The Best Potting Soils for Dahlias, Lilies, and Begonias?

 

“What kind of potting soil should I use for Dahlias, Asiatic and oriental lilies, and begonias?” Question from Luciana of Portland, Oregon

Answer: Each flowering plant has some distinct needs when it comes to soil moisture, pH, and quality. The right kinds of fertilizers also help these flowers bloom at their best.

Soil and Fertilizer for Dahlias

Potted Dahlias need porous soil that drains well, holds moderate moisture and has a slightly acid to neutral pH (6.2 to 7). I recommend our Black Gold® All Purpose Potting Mix or OMRI Listed Black Gold® Natural & Organic Cocoblend Potting Mix, which is approved for organic gardening. Both potting soils have all the right characteristics. When picking a fitting fertilizer, choose one formulated for blooming plants. Proven Winners Premium Continuous Release Fertilizer is a good choice. Adding Proven Winners Premium Water Soluble Plant Food as directed will also help boost flowering through summer.

Soil and Fertilizer for Asiatic and Oriental Lilies

Lilies of all types grow best in soils that are well-drained and rich in organic matter. The ideal pH should be a little more acidic (5.5 to 6.5), but neutral soils are also tolerated. Once again, I recommend our Black Gold® All Purpose Potting Mix in addition to another of our OMRI Listed mixes, Black Gold Natural & Organic Ultra Coir, which is rich in organics but drains well. Here, it is best to choose a fertilizer specially formulated for summer bulbs. These tend to be balanced fertilizers with added bonemeal, and there are many fine choices on the market.

Soil and Fertilizer for Begonias

Fast-draining soils that are light and fertile are preferred by begonias. Their tubers or fibrous roots are prone to rot, so soils that hold onto water too well can be detrimental. Once again, a slightly acid pH (5.5 – 6.5) is needed. Black Gold® Natural & Organic Potting Mix is a good soil choice. Adding a little extra Black Gold Perlite for added drainage is also recommended. Proven Winners Premium Continuous Release Fertilizer helps boost flowering and performance in begonias. The occasional addition of Proven Winners Premium Water Soluble Plant Food will also help boost flowering.

Have a great gardening season!

Jessie Keith

Black Gold Horticulturist

The Best Disease-Resistant Roses

Knock Out roses of all colors are everblooming and resist common rose diseases.

Roses are among the most beautiful flowers on the planet, but they are also prone to some of the nastiest foliar diseases as well.  The three worst of these are rose black spot (Diplocarpon rosae), powdery mildew (order Erysiphales), and rose rust (Phragmidium spp.), but new roses are challenging their damage. Many of the largest rose growers and breeders have developed gorgeous disease-resistant roses that are absolutely outstanding.

Most of the finest disease-resistant roses are shrub roses, but there are a few other forms on the list. All these roses bloom from late spring until frost. Here are a few favorites to consider.

Best Disease-Resistant Roses

Shrub Roses

Crazy Love is a beautiful shrub rose bred by Kordes. (Image thanks to Kordes.)

The grandiflora shrub rose Crazy Love™ Sunbelt® (USDA Hardiness Zones 5-9, 5′ x 3′)  has unusual, orange and yellow, cup-shaped flowers that are fully double and very fragrant. It is generally resistant to common foliar diseases of roses and a vigorous nonstop bloomer.

Nicole® (Zones 6-10, 4′ x 3′) is a beautiful floribunda shrub rose that I am buying this year for my front border. It has 4-inch wide blooms that are snow-white with deep rose edges.  The stunning shrub rose is remarkably disease resistant.

Nicole is a remarkably beautiful shrub rose that I will be planting in my garden this year. (Image by Garitzko)

One favorite new yellow-flowered rose is the floribunda shrub rose Golden Fairy Tale® (Zones 5-9, 4′ x 4′). It’s another that I have added to my must-buy list this year. The award-winner has bright golden-yellow double blooms that are very fragrant and flower in abundance. Notable disease resistance makes it an effortless variety for the garden. Think seriously about this one.

The compact floribunda rose, ‘Brilliant Veranda’ (Zones 5-9, 2′ x 3′) is brilliant red and just the right size for a flower-filled veranda, as the name suggests. Its blooms almost glow, and the plants show very good disease resistance.  Plant it in front of beds with taller plants behind it to light up the garden.

Shrub roses in the Knock Out® Series are possibly too familiar, since everywhere I go in my hometown of Bloomington, Indiana, they are planted outside practically every landscaped business front.  But there is a reason for that. The classic Double Knock Out® rose has gorgeous, double, cherry red flowers on shrubby plants that are very tough and easy to maintain. There are many other colors in the series, including those in the shades of yellow, apricot, and pink.

The new flowers of ‘Princess Ann’ are deepest pink, fading to pure rich pink. It is named for Her Royal Highness, the Princess Royal. (Image thanks to David Austin Roses)

English garden roses of all kinds are sold at David Austin Roses, the most famous rose-breeding company in the world. David Austin has produced the most beautiful English roses that bloom the whole season through. He also bred for disease resistance and fragrance. I have picked out two of my favorites that you will love forever.

The fragrant ‘Olivia Rose Austin’ (Zones 4-11, 4′ x 3′) is a classic English rose of pale pink that has cupped, double flowers with a dense rosette of petals in the center.  The flowers have a fruity fragrance. The darkest pink ‘Princess Anne’ (Zones 4-11, 4′ x 4′) has highly fragrant clusters of fluffy double flowers that lighten a bit as they get older.  These are held upright over disease-resistant leaves.

At Last® shrub roses are everbloomers with a light, sweet fragrance. (Image thanks to Proven Winners®)

Finally, Proven Winners® has a variety of tough, disease-resistant roses. Of these, At Last® (Zones 5-9, 3′ x 3′) is a fragrant beauty that will bloom nonstop through summer and into fall. The shrubs have glossy foliage and pale amber-orange flowers that are fully double and sweetly fragrant.

Other Roses

From miniatures to climbers, there are many other roses that defy diseases. The disease-resistant hybrid tea rose Gypsy Soul Eleganza® (Zones 5-9, 3.5′ x 2.5′) has deep violet-red flowers with long upright canes that are perfect for cutting long-stemmed roses. Petite Knock Out® (Zones 5-10, 18″) is a brand new miniature rose that has all of the traits of the classic double red Knockout® (mentioned above) but in truly miniature form. The climbing rose ‘Climbing Pinkie‘ (Zones 6-11, 8-12’) is one of the few disease-resistant climbers. The flowers are rose-pink and hang in clusters over the leaves.  It can be trained along a fence or wall, or if you want to be really English, around your front door.

Spring is the best time to plant roses. Feeding the soil and fertilizing your shrubs at planting time will give them a great start. For more details about how to grow and plant shrub roses organically, please watch the video below by my daughter, Jessie.