perennial

More perennials, please!

More Perennials Please.jpg

We keep a tentative schedule for our weekly topics.  Today’s topic was to be “Watering Tips for the Summer.”  But that would be a very short, probably one sentence tip: “Turn the water off!” 

Our goal every week is to address issues we are seeing in lawns and landscapes as we are out providing lawn care services.  Most problems we are seeing are related to too much moisture and poor drainage.  The Oklahoma City area received, on the average, another 2” of rain this week.  Soil moisture readings are at 100%.  This means soils can not absorb any additional water and if you add any it will just run off.  By mid-week if we have not received any more rainfall, inspect your landscape and water only if needed.

So, let’s talk about something more interesting than “turn your water off” - let’s talk about perennials!

Traditionally a big believer in lots of annual color, I have been gradually reducing the amount of annual color in my landscape by adding perennials.   

My landscape has always included some perennials.  But, because they don’t bloom all season and often their foliage is unattractive after the blooms have faded, my style has been to keep them in the background.

I still believe that annual color provides the most season long impact.  Areas close to the front doors, along the front walks, and key areas around our outdoor living spaces still look best planted with pansies and bulbs in the fall, and replanted with various heat loving annuals in April and May.  You can’t beat the impact of bright annual color! 

But I’m glad I have been gradually adding more perennials to the landscape because this year perennials have been stunning. 

There are so many perennial choices. There are more perennials than you could ever cover in one writing.  Books and books have been devoted to perennials, but I have a few favorites.  Each of these have found a home in my landscape, although none of them last the entire season, as a group, they add interest from spring to fall. 

Creeping Phlox (Phlox stolonifera) .  The first to welcome spring each year.  Creeping phlox produces a spring-like carpet in pastel hues of white, lavender, red and pink.  Creeping phlox is a moderate grower that can spread up to 2’ but only reaches 4-6” in height.  It prefers full sun but will tolerate some shade each day.  Borders, walls, and around boulders are where it looks best.  In my garden, you will find it cascading over a rock retaining wall. It tolerates most soils as long as it is well drained.  The plant requires little maintenance.  Mites are about the only insect problem it will have.  

Creeping Phlox (Phlox stolonifera).  The first to welcome spring each year.  Creeping phlox produces a spring-like carpet in pastel hues of white, lavender, red and pink.  Creeping phlox is a moderate grower that can spread up to 2’ but only reaches 4-6” in height.  It prefers full sun but will tolerate some shade each day.  Borders, walls, and around boulders are where it looks best.  In my garden, you will find it cascading over a rock retaining wall. It tolerates most soils as long as it is well drained.  The plant requires little maintenance.  Mites are about the only insect problem it will have.  

Dianthus (Dianthus).    It works well as a border, in small groupings, around boulders or as a single plant reaching 10-15” tall with a spread of 12-24”.  They bloom in late spring to early summer in rose, pink, white, red.  They like full sun but will take some dappled shade or afternoon shade.  Just like creeping phlox, they are a cool season lover.  They will grow in most soils, prefer alkaline soils, but waterlogged soil will cause crown and root rot.   Heavy mulching near the crown of the plant can be detrimental. Late March through April and into May is the peak bloom time. Light feeding in the spring with a complete fertilizer of phosphorus, potassium and low nitrogen is recommended.  Other than an occasional aphid or powdery mildew issue, they do not have many problems.  There are more than 300 varieties of dianthus to choose from.  My all-time favorite is ‘Firewitch’.  It has a silver-green foliage and with a vibrant pink bloom.

Dianthus (Dianthus).   It works well as a border, in small groupings, around boulders or as a single plant reaching 10-15” tall with a spread of 12-24”.  They bloom in late spring to early summer in rose, pink, white, red.  They like full sun but will take some dappled shade or afternoon shade.  Just like creeping phlox, they are a cool season lover.  They will grow in most soils, prefer alkaline soils, but waterlogged soil will cause crown and root rot.   Heavy mulching near the crown of the plant can be detrimental. Late March through April and into May is the peak bloom time. Light feeding in the spring with a complete fertilizer of phosphorus, potassium and low nitrogen is recommended.  Other than an occasional aphid or powdery mildew issue, they do not have many problems.  There are more than 300 varieties of dianthus to choose from.  My all-time favorite is ‘Firewitch’.  It has a silver-green foliage and with a vibrant pink bloom.

‘May Night’ Salvia (Salvia x sylvestris).   Sage type flower spikes of deep bluish-purple that will add color in April, May and early June. The best flower show will be in full sun but it will tolerate a little dappled shade each day.  The plant grows 12-18” tall with flower spikes reach 24”.  The plant looks great in the middle of the garden planted behind creeping phlox or dianthus, and in front of Shasta daisy or Black-eyed Susan.  The leaves often become tattered later in the summer. Keep faded blooms removed to maximize bloom period and pruning the plants after blooming may result in a few fall blooms. In the early spring, before new growth emerges, remove the dormant foliage.  Salvia tolerates clay soils but will struggle with root rot if the soil stays saturated.

‘May Night’ Salvia (Salvia x sylvestris).  Sage type flower spikes of deep bluish-purple that will add color in April, May and early June. The best flower show will be in full sun but it will tolerate a little dappled shade each day.  The plant grows 12-18” tall with flower spikes reach 24”.  The plant looks great in the middle of the garden planted behind creeping phlox or dianthus, and in front of Shasta daisy or Black-eyed Susan.  The leaves often become tattered later in the summer. Keep faded blooms removed to maximize bloom period and pruning the plants after blooming may result in a few fall blooms. In the early spring, before new growth emerges, remove the dormant foliage.  Salvia tolerates clay soils but will struggle with root rot if the soil stays saturated.

Cutting Salvia back after it has finished blooming for the season.

Cutting Salvia back after it has finished blooming for the season.

Daylily (Hemerocallis) .  With hundreds of cultivars there are too many colors to list.  Daylilies range from 10-36” tall and 12-24” wide.  Depending on the variety, blooms start in early summer and extend into late summer with a successive blooming habit that last 4-6 weeks.  Plant in sun to partial shade with no more than a half day of shade.  They are drought tolerant, pest resistant – an overall tough plant. With a clump type growth, they are dynamic planted in a mass grouping. Well drained fertile soil is best, but they are very adaptive to a wide range of soils.  Leave dormant foliage until new foliage emerges in the spring.  Fertilizer in early spring and again in early summer.  Clumps can be divided every 3-5 years in the fall.  Remove spent flower stocks to encourage more blooms.  The most common yellow daylily is ‘Stella de’ Oro’.  ‘Pardon Me’ is a great red daylily.  Planting daylilies behind liriope (monkey grass) will help cover up the unattractive foliage as it begins to fade in late summer.  Our daylilies started putting on their early summer show this week

Daylily (Hemerocallis).  With hundreds of cultivars there are too many colors to list.  Daylilies range from 10-36” tall and 12-24” wide.  Depending on the variety, blooms start in early summer and extend into late summer with a successive blooming habit that last 4-6 weeks.  Plant in sun to partial shade with no more than a half day of shade.  They are drought tolerant, pest resistant – an overall tough plant. With a clump type growth, they are dynamic planted in a mass grouping. Well drained fertile soil is best, but they are very adaptive to a wide range of soils.  Leave dormant foliage until new foliage emerges in the spring.  Fertilizer in early spring and again in early summer.  Clumps can be divided every 3-5 years in the fall.  Remove spent flower stocks to encourage more blooms.  The most common yellow daylily is ‘Stella de’ Oro’.  ‘Pardon Me’ is a great red daylily.  Planting daylilies behind liriope (monkey grass) will help cover up the unattractive foliage as it begins to fade in late summer.  Our daylilies started putting on their early summer show this week

Shasta Daisy (Chrysanthemum x superbum).   Classic daisy appearance of white petals around a yellow center.  They grow in clumps 1-2’ wide and 2-3’ tall.  Best if planted in fertile soil that drains well.  The more sun they receive the more they will bloom.  Shasta Daisies start blooming in early summer and can last until early fall.  They make great cut flowers.  We are enjoying an arrangement of white daisies and hydrangea blossoms from the garden this weekend.  Keeping the faded blooms cut will extend the color show.  After the foliage goes dormant in late fall, cut the stems back to 1-2”.  They respond well to light fertilizer in the spring.  Daisies perform best if they are divided every 3-5 years.  Considered as a low maintenance plant, aphids are about the only insect you may see.  ‘Becky’ is a favorite variety.

Shasta Daisy (Chrysanthemum x superbum).  Classic daisy appearance of white petals around a yellow center.  They grow in clumps 1-2’ wide and 2-3’ tall.  Best if planted in fertile soil that drains well.  The more sun they receive the more they will bloom.  Shasta Daisies start blooming in early summer and can last until early fall.  They make great cut flowers.  We are enjoying an arrangement of white daisies and hydrangea blossoms from the garden this weekend.  Keeping the faded blooms cut will extend the color show.  After the foliage goes dormant in late fall, cut the stems back to 1-2”.  They respond well to light fertilizer in the spring.  Daisies perform best if they are divided every 3-5 years.  Considered as a low maintenance plant, aphids are about the only insect you may see.  ‘Becky’ is a favorite variety.

Black-Eyed Susan (Rudbeckia grandiflora).   Daisy like golden-yellow flower petals surround a dark brown or black center reaching 2-4’ and spreading 2’.   The large flower blooms (2-4”) will be arriving in the next two weeks and will continue into July.   And, if you keep spent blooms trimmed off, you will get a few blooms in the fall. Plant in sun to partial shade.  As a native prairie plant, you will find it to be low maintenance.  It tolerates most soils but prefers well drained. 

Black-Eyed Susan (Rudbeckia grandiflora).  Daisy like golden-yellow flower petals surround a dark brown or black center reaching 2-4’ and spreading 2’.   The large flower blooms (2-4”) will be arriving in the next two weeks and will continue into July.   And, if you keep spent blooms trimmed off, you will get a few blooms in the fall. Plant in sun to partial shade.  As a native prairie plant, you will find it to be low maintenance.  It tolerates most soils but prefers well drained. 

Because of its height, plant in the middle of a bed or as a background to lower perennials, such as dianthus or salvia. The plant can be divided every 3-5 years.  Remove dormant foliage anytime in the fall or winter.  It can develop powdery mildew if in too much shade.  Minimal feeding is required.  Keep a watch out for occasional aphid problem. 

Because of its height, plant in the middle of a bed or as a background to lower perennials, such as dianthus or salvia. The plant can be divided every 3-5 years.  Remove dormant foliage anytime in the fall or winter.  It can develop powdery mildew if in too much shade.  Minimal feeding is required.  Keep a watch out for occasional aphid problem. 

Coneflower (Echinacea).   A native   prairie plant with purple or white blooms 2-4” in diameter.    Just like Black-Eyed Susan it reaches 2-4’ in height and spreads out 2-3’ and makes a good show planted in the back or sides of the garden.  But, it also works well as a single specimen.  Plant in sun to partial shade.  It is one of the longest summer bloomers with a show that last 5-8 weeks. The coarse texture of the leaves makes them well suited near softer-textured plants such as ornamental grasses.  It enjoys well-drained, fertile soil.  Removing faded flowers will encourage more blooms.  Remove dead foliage in the winter.  Coneflower is fairly disease tolerant and responds to feeding early in the growing season, and also likes to be mulched.

Coneflower (Echinacea).  A native prairie plant with purple or white blooms 2-4” in diameter.    Just like Black-Eyed Susan it reaches 2-4’ in height and spreads out 2-3’ and makes a good show planted in the back or sides of the garden.  But, it also works well as a single specimen.  Plant in sun to partial shade.  It is one of the longest summer bloomers with a show that last 5-8 weeks. The coarse texture of the leaves makes them well suited near softer-textured plants such as ornamental grasses.  It enjoys well-drained, fertile soil.  Removing faded flowers will encourage more blooms.  Remove dead foliage in the winter.  Coneflower is fairly disease tolerant and responds to feeding early in the growing season, and also likes to be mulched.

Hardy Verbena (Verbena).   This low growing (4-6”) spreading (2-3’) perennial thrives in summer heat while producing purple, pink, red or white blooms.  Verbena is not picky about soil type, but requires full sun.  When it gets more than 2-3 hours of shade per day, its biggest problem is powdery mildew disease increases.  The low growing nature makes it perfect for the front of beds, along walks and cascading over walls and slopes.  It also looks great in pots and window boxes.  Good drainage and fertile soils needed and with consistent irrigation blooms and spread will increase. Feed in spring and after first flush of heavy blooms.  Don’t fertilize after July.  Verbena likes mulch to insulate roots and hold in moisture.  Sheering the plant just below spent blooms will encourage growth and more flowering.  My favorite variety is ‘Homestead Purple’. 

Hardy Verbena (Verbena).  This low growing (4-6”) spreading (2-3’) perennial thrives in summer heat while producing purple, pink, red or white blooms.  Verbena is not picky about soil type, but requires full sun.  When it gets more than 2-3 hours of shade per day, its biggest problem is powdery mildew disease increases.  The low growing nature makes it perfect for the front of beds, along walks and cascading over walls and slopes.  It also looks great in pots and window boxes.  Good drainage and fertile soils needed and with consistent irrigation blooms and spread will increase. Feed in spring and after first flush of heavy blooms.  Don’t fertilize after July.  Verbena likes mulch to insulate roots and hold in moisture.  Sheering the plant just below spent blooms will encourage growth and more flowering.  My favorite variety is ‘Homestead Purple’. 

Garden Mum (Chrysanthemum x moratorium).   Typically thought of as an annual, but they make a great perennial for fall color with shades of pink, red, white and yellow.  Plant height and width are both 1-3’ resulting typically in a round shape.  They produce a wonderful burst of color for 2-4 weeks in late September and October.  Mums will tolerate light shade but prefer full sun.  To survive the winter as a perennial they need moisture and good drainage. Therefore, add an ample amount of compost when planting in our clay soils.  Dormant foliage can be removed anytime during the winter or in the spring when new growth emerges.  Mums will bloom a little in the spring or early summer.  Once the early blooms fade, keep the plant sheared to the shape and height you prefer.  Stop shearing after the first of July.  When you shear a mum during the last half of the summer, you are removing the flower buds for the fall.

Garden Mum (Chrysanthemum x moratorium).  Typically thought of as an annual, but they make a great perennial for fall color with shades of pink, red, white and yellow.  Plant height and width are both 1-3’ resulting typically in a round shape.  They produce a wonderful burst of color for 2-4 weeks in late September and October.  Mums will tolerate light shade but prefer full sun.  To survive the winter as a perennial they need moisture and good drainage. Therefore, add an ample amount of compost when planting in our clay soils.  Dormant foliage can be removed anytime during the winter or in the spring when new growth emerges.  Mums will bloom a little in the spring or early summer.  Once the early blooms fade, keep the plant sheared to the shape and height you prefer.  Stop shearing after the first of July.  When you shear a mum during the last half of the summer, you are removing the flower buds for the fall.

These are some of my favorites -- but, with so many types of perennials, I am always finding another one to try in the landscape. 

What are your favorites? 

One final thought – I have noticed a trend toward mixing herbs in perennial garden. Not only will herbs add different textures and tones to the landscape, but you also get the benefit of having fresh herbs, which are always better, on your dinner table.

Send us an email or give us a call (405)367-3873, we would love to hear what is working for you!

Lorne Hall

Hall | Stewart Lawn + Landscape