Garden Notes

Garden Notes

Ornamental Grasses 201 – Nice Natives

Although most of the garden-worthy grasses we sell as ornamentals are exotic, there are many beautiful native grasses to choose from in commerce.  Whenever possible, we like to encourage our customers to try using native grasses.  They grow well, require little care, and have evolved with the natural vegetation of the island.  Native plants contribute to the overall beauty and health of our planted landscapes as well as the native ecosystem.  They also support the fauna that has developed here over thousands of years.

There are many native grasses found here, growing in a wide variety of habitats; from the shore line into the more fertile interior areas of the island.  The most popular species of native grasses that we sell is Panicum virgatum, commonly called Switch Grass or Panic Grass.  There has been a lot of work done with these grasses over the years, so there are many cultivars to choose from with a variety of heights, habits and colors to the foliage.  For more information on some of the various Panicum grasses check out this post: https://surfinghydrangea.com/switch-grass-2086

Another of our naturally-occurring grasses that is slowly becoming more popular is Schizachyrium scoparium, Little Bluestem.  If you walk your dog at Tuppancy Links, you are very familiar with this grass: it’s one of the predominant species found growing on the links, especially beautiful in the fall when it takes on coppery-red, orange and auburn hues.  Backlit by the sun at the end of the day, it’s magic.  Little bluestem grows best in full sun on moderately fertile, well-drained soils without much additional water.  The narrow bluish foliage appears in mid to late spring from the base of mostly clumping plants.  By August, the plant reaches its full height of about 2-3′ and begins to flower.  The flowering stems rise above the foliage, producing tight sprays of fluffy flowers.  Gardeners have found that when little bluestem is over-irrigated or grown with too much fertility it can get floppy – avoid this problem by planting it in un-amended soil and only watering during establishment and prolonged periods of drought.

Whether planted in drifts or sprinkled here and there among perennial flowers, this is a wonderful addition to almost any island landscape.  Several cultivars are available including ‘The Blues’ whose blue foliage is steaked with purple and accented with red stems.  ‘Standing Ovation’ is another great cultivar that is touted to be reliably sturdy with an upright, non-flopping, habit.

For a plant that will tolerate shadier conditions, try Carex pensylvanica, Pensylvania Sedge.  Although, it’s not technically a true grass, this short (6-12″) plant has a delicate, grassy look with arching foliage and spreads by rhizomes to make a pretty ground cover.  It looks especially nice in dappled shade under deciduous trees but grows well in fully shaded areas.

Several other grasses native to North America are also well-worth planting.  For a fine textured, loose look  consider Sporobolus heterolepsis, Prairie Dropseed, Deschampsia cespitosa, Tufted Hair Grass or Descampsia flexuosa, Crinkled Hair Grass.

 


Ornamental Grasses 101

Ornamental grasses are beautiful, deer-resistant and easy to grow.  Although there are many lovely native grasses, the majority of ornamental varieties are introduced from Asia.  We sell hundreds upon hundreds of these plants each year and their popularity seems to keep growing.

Most ornamental grasses are clumping, perennial, warm-season grasses that will come back for years.  Although there are many species and varieties available, the most popular today are Maiden Grasses, Miscanthus sinensis and Fountain Grasses, Pennisetum alopecuroides.  If sited in full sun and grown on average soil, these plants require little care – just cut them back to a few inches above the ground during the winter and irrigate during dry spells in the summer.  Maiden grass do best if dug and divided every 5 years or so, which is a major undertaking!  Make sure to keep this extra step in mind when planting them, as the clumps can get very large as they age.

The most popular grasses are listed below:

Miscanthus sinensis ‘Gracillimus’:  Gracillimus Maiden Grass.  The most common large ornamental grass sold.  Broad, vase shaped form, reaching 6′ tall.  Deep-green, finely textured blades have a narrow white mid-rib.  Silver/buff-colored flowers appear above the foliage in late summer and persist into the winter. After a number of years, the clumps will spread to 3+ feet wide, with the foliage spreading out to at least 5 feet.    The dense crown of the plant may die out in the center, signaling that it’s time to divide.  Division is best done in late spring, just as new growth has begun to emerge.

Miscanthus sinensis ‘Adagio’: Adagio Maiden Grass.  Another large grass, similar to ‘Gracillimus’, but a foot or two smaller in size overall.

Pennisetum alopecuroides ‘Hameln’:  Dwarf Fountain Grass.  Rounded grass with a cascading habit, 2 – 2.5′ tall and wide.  Mid-green foliage changes to yellow in fall.  Fluffy, bottle brush-shaped flowers appear in mid August above the foliage on narrow stems.

Panicum virgatum, cvs.: Switch Grass.  Many varieties of this native grass are now in commerce.  Generally, upright 3-5′ tall.  Airy inflorescences appear in mid-summer.  Breeding in these grasses has focused on improved form and foliage color.  ‘Heavy Metal’, an old favorite, has a metallic blue sheen to the leaves and average height of 5′.  For a more compact variety, try ‘Cape Breeze’ a dwarf that stays about 2.5′ tall.  Many other cultivars are available with purple or blue foliage, some reaching 8′, making a major statement.  For more information on switch grass check out: https://surfinghydrangea.com/switch-grass-2086

Nassella tenuissima aka Stipa tenuissima: Mexican Feather Grass.  One of the few cool-season ornamental grasses, this plant has gained in popularity in recent years, especially used as a mass planting.  The light green, fine-textured foliage emerges in late spring.  This fresh growth appears upright early in the growing season, but becomes more arching as it elongates to 1-2′ in height, with a more fountain-like habit.  In mid-summer the airy inflorescences emerge and the foliage changes to a beachy, buff-tan.

These are only a handful of the grasses that we stock.  On any given day, we will have many more to choose from.  We’d be happy to show them to you.


Calamint

Nearly every gardener that has visited the nursery this year has spoken about the uptick in rabbit and deer damage this year. The rabbits are ravenous and the deer are nearly impossible to keep out, short of installing a professional farm-grade border fence. These animals have become more than an nuisance – they are a serious problem.  Year after year, the list of plants deer and rabbits won’t destroy has gotten much shorter.  Russian sage, catmint, lavender and grasses are still mostly reliable (although we had a whole crop of catmint eaten early this spring).  Another favorite of ours is calamint, Calamintha nepetoides cvs.  

The fuzzy, menthol-scented leaves of this plant make it highly resistant to rabbit and deer browsing.  And it blooms for months – seriously!  This compact plant is covered in tiny white or blue flowers from mid-summer well into the fall.  It makes an excellent groundcover, planted en masse, but also looks great in the front of mixed perennial borders.  Calamintha does seed around a little bit, but I’ve never felt it to be a problem.  Another consideration with this plant is how late it is to come up in the spring.  Because it is one of the last perennials to get going, I often plant it closer than recommended so that I get the coverage I want earlier in the season.  If you want to get the best out of this plant, site it in a sunny location with well-drained, healthy soil.  There are several cultivars available for sale, with newer introductions entering the market recently.

  • Calamintha nepeta subsp. nepeta:  Icy blue/white flowers.  Fuzzy leaves.  Spreads a little more readily than others as stems root along the edges of the clump.  1-1.5′ tall.
  • Calamintha nepetoides ‘Montrose White’:  Clear white flowers that appear icy blue in cooler weather.  Less prominent fuzz on the leaves.   Leaves appear darker green than other varieties, setting off the flowers well. 1-1.5′ tall.
  • Calamintha nepetoides ‘White Cloud’:  Clear white flowers.  Fuzzy leaves.  1-1.5′ tall.
  • Calamintha nepetoides ‘Blue Cloud’:  Very similar to white cloud, but with icy blue flowers.
  • Calamintha nepetoides ‘Marvelette Blue’:  The largest and most saturated flowers we’ve seen on a Calamint so far.  Earlier flowering than other varieties.  8″ tall.

Stokes Aster ‘Peachie’s Pick’

 

There are so few plants that have a true blue flower in the garden – there seems to be loads of magentas, indigos, purples and violets; but so little blue.  Powder blue, in particular is very hard to get into the mix.  There are some annuals that have just that sort of blue, like Salvia uliginosa, and Tweedia, but most perennials have a purple or pink undertone to their “blue” flowers.  Stokesia laevis ‘Peachie’s Pick’ is in this vein, but it is very close to sky blue, to my eye.

These dependably perennial plants have glossy, thick medium green leaves that form a pleasing mound during the spring and early summer.  In high summer many flower stems arise from the clump, reaching about 18″ or so tall.  The entire plant is covered in aster-like flowers when the buds open, slowly over a period of weeks on sturdy stems. ‘Peachie’s Pick’ also looks great in a vase, so consider adding her to your cut flower selection.

Plant this beautiful but tough plant in good, but well-drained soil in full sun, and enjoy it for years to come!


Plume Poppy

At Surfing Hydrangea, we sell a wide variety of “bread and butter” plant material that landscapers are looking for every day, like cherry trees, catmint and fountain grasses.  Keeping lots of stock of those items is great for business, but it’s always the plants that I’ve never heard of, or seen in person that get me jazzed up for gardening again when I’m a little burned out.  My favorites are often the new introductions and hard-to-find perennial treasures that Britt brings in for the courtyard.

A few weeks ago, I was unloading a rack of plants when I came across a perennial with unique foliage, reminiscent of oak leaves.  I had never even heard of it, so I was delighted.  The grower describes the foliage of Macleaya microcarpa ‘Kelways Coral Plume’ as “commanding and tropical in appearance” and I definitely agree.  This thing is amazing.  The blue-grey leaves are about the size of my hand and run all the way up the stalk of this large plant.  When grown in sun, on well-drained fertile soil, plume poppy will reach 6 or more feet tall and spread out to occupy a space of about 4 feet.  The foliage is topped with feathery, coppery-pink flowers in high summer.  In fall, the leaves take on a tan hue, that fits right in with autumnal foliage.

I’ve been so interested in this plant that I’ve had one planted in our garden at the nursery so that we can enjoy it for years to come.  As I write this post, we still have a few in stock.  Why not give them a try in your garden?!

 

 


Spanish for Gardeners

One of my favorite things about living on Nantucket is the wide range of people from all over the world that I have the pleasure of meeting and working with.  Over the last few years, I’ve been trying my best to pick up some useful Spanish words and phrases to help me work along side the many people of Latin American descent in landscaping on the island these days.  Although there are many ways to express the same idea in Spanish, some of the following words and constructions have been quite helpful to me.

I’ll be adding to this post off an on, as time permits, so check back to see what other things we can learn to say in Spanish!  Also, if there are any errors (I’m sure I’ll make some as I am not fluent in Spanish), or you know of a better Spanish word or phrase than I am listing, please let me know and I’ll add it to the growing list.  Thanks!  brad@surfinghydrangea.com

Words that describe plants and their parts:

Plant – La planta

Tree – El árbol

Shrub – El arbusto

Flower – La flor

Ornamental Grass – El zacate

Weed – La mala hierba

Trunk –  El tronco

Branch – La rama

Twig – La ramita

Leaf – La hoja

Root – La raíz

Words for tools used in gardening:

Shovel – La pala

Rake – El rastrillo

Saw – La sierra

Hand pruners – Las tijeras

Shrub shears – Las tijeras grandes

Twine – La pita

Gloves – Los guantes

Wheel barrow/cart – La carreta

Ladder – La escalera

Tarp – La carpeta?, la iona?

Truck – El truck, el carro

Lawn mower – El mower, el cortacésped?

Hedge trimmers – La motosierra?

Chainsaw – La motosierra?

Bucket – El bote


Sea Buckthorn

Working at the nursery as long as I have, there aren’t a lot of landscape plants suitable for Nantucket that I’m not familiar with, so I’m always pleased when I have the opportunity to learn something new.  Last fall, a customer asked about sea buckthorn, a plant I have absolutely no experience with.  After a little research, I think it might be a useful plant for some of the islands’ challenging sea-side properties.  We brought some in for a job this spring, and decided to order some extra for stock.  This plant should be a good choice for growing in close proximity to the shore, where soils are extremely sandy, drainage is excellent and sun is plentiful.

Hippophae rhamnoides has abundant grey/green, skinny leaves on thorny, branches.  Their habit is variable, sometimes reaching the size of a small tree, but they often treated as rangy shrubs.  The plants I have seen growing on Nantucket look quite a lot like Russian olives, although spinier and with narrower leaves.  These plants are dioecious, meaning that there are separate male and female plants.  If female plants are pollinated by males, they will have an abundant fruit set of small, yellow/orangy berries.  Native to the Northern regions of Europe, Asia and North America, sea buckthorn it is extremely cold hardy and can be expected to survive during prolonged periods of extreme cold.

There are many varieties in cultivation.  We’re currently stocking ‘Chuysaka’, ‘Hergo’ and ‘Juliet’.


Asian Wisteria

I’ve spent many, many hours on ladders and on top of roofs and pergolas as a professional gardener on Nantucket.  The bulk of those hours have been spent on rose care, but pruning and training wisteria is actually one of my all-time favorite garden tasks.  This graceful, spring-flowering vine requires a lot of work to keep in bounds and looking its best.  This is especially true of the Asian varieties, which are quite a bit more rampant than their North American cousins.  Although there are many cultivars and hybrids, Asian wisteria can generally be separated into to groups: Japanese and Chinese.

 

 

Japanese Wisteria, Wisteria floribunda

Flowers open over the course of days, starting at the top of the cluster.  Tendrils twine counter clockwise.

‘Black Dragon’ aka ‘Violacea Plena’ aka ‘Yae Koburyu’:  Deep purple double flowers

‘Domino’ aka ‘Issai’:  Lilac blue flowers

‘Lawrence’:  Pale lavender flowers

‘Longissima Alba’ aka ‘Siro Noda’:  Long white flowers

‘Snow Showers’:  White flowers

‘Honbeni’:  Pink flowers

Chinese Wisteria, Wisteria sinensis

Flowers tend to open all at once.  Tendrils twine clockwise.

‘Blue Moon’:  Bicolor blue flowers

‘Caroline’:  Very fragrant, bluish purple flowers

‘Cooke’s Purple:  Fragrant, bluish purple flowers

‘Jacko’:  Selection of Alba; very fragrant, white flowers

‘Prolifica’:  Bluish violet flowers

‘Royal Purple’:  Deep violet flowers

If you’re interested in how to prune these vines, check out our articles and Youtube videos on the subject:

Video – Summer pruning of Wisteria

Video – Winter pruning of Wisteria

Article – Summer Pruning How-to

Article – Winter Pruning How-to


Old Fashioned Lilacs

Having been a gardener and nurseryman on Nantucket for over 20 years, I’ve amassed a long list of favorite plants.  From year to year, the list changes as some plants become over-used and improved selections and exciting introductions hit the market.  Nonetheless, there are a few plants that will have a special place in my heart no matter what.  Old-fashioned lilacs are one of those.

When I was a child, my grandparents, Jim and Isabelle, had some common lilacs in their yard in Antigonish, Nova Scotia.  Fully mature, their stems had widened into trunks and they were so tall that we called them “lilac trees”.  Grandma would send us outside with kitchen scissors to cut the flowers and bring them indoors.  There were always extra to share, and we often brought some home to my Mom for our house too.  I also clearly remember Mom sending me down to our neighbor Theresa’s house to ask for a cutting of her lilac shrub.  We planted it at the edge of the lawn.  That lilac is now taller than I am and a lovely way to remember Theresa, who so kindly gave it to us, thirty years ago.

There are currently twelve species in the genus Syringa but only a few are cultivated in North America as garden plants.  Syringa vulgaris, common lilac, is the plant that comes to mind when most of us think of traditional lilacs.  There are many cultivars available, with flowers that range in color from crisp white, to deep purple-red.  There also numerous hybrids on the market that make great garden plants.  These lanky, suckering, shrubs grow 15-20 feet tall and can easily spread to occupy a space of 5 or more feet wide.  In order to keep lilacs looking their best, they do require a good pruning regimen.  Since the flowers appear on old wood at the tips of the branches, they can stretch out of reach as the plants get older.

Pruning is best done just after the flowers have faded in mid summer.  Keep in mind these objectives, while pruning:

  • Remove diseased or damaged wood
  • Encourage strong growth at the base of the plant, in order to combat the leggy habit
  • Keep the height of the plant in check, so that flowers can be enjoyed
  • Remove spent flowers, if desired

Consider following these steps while pruning:

  1. Take a good look at the overall structure of the plant.  Consider removing one or two of the oldest stems completely, at ground level
  2. Consider removing a few wayward branches
  3. Make several cuts at different levels to encourage new, bushy growth throughout the plant.
  4. Remove dead heads, making pruning cuts just above healthy buds.
  5. Assess the overall height of the plant, and make deeper, staggered cuts to reduce the height.

Check out our pinterest board for photos of old-fashioned lilacs we’ve carried in the past:

https://www.pinterest.com/surfhydrangea/luscious-lilacs/

Here’s a quick reference guide to varieties we’ve had in the past:

Syringa vulgaris aka common lilac:  Light purple flowers.  10-12′

Syringa vulgaris ‘Adelaide Dunbar’:  Deep purple buds open to double paler purple flowers.  French lilac.

Syringa vulgaris ‘Agincourt Beauty’:  Very large, deep purple flowers. 10-12′.

Syringa vulgaris ‘Charles Joly’:  Deep purple, double flowers.  8-10′.

Syringa vulgaris ‘Edward J Gardner’:  Light pink, double flowers.  8-10′.

Syringa x hyacinthiflora ‘Equinox Valley’:  Reddish-purple buds open to double light purple flowers.  8-15′.

Syringa x hyacinthiflora ‘Maidens Blush’:  Light pink flowers.  Canadian lilac.  Early flowering.  10-12′.

Syringa vulgaris ‘Madame Lemoine’:  White, double flowers.  French lilac. 15′.

Syringa vulgaris ‘Monge’: Reddish-purple flowers.  French Lilac. 8-12′.

Syringa x hyacinthiflora ‘Mount Baker’:  White flowers.  Canadian lilac.  Early flowering.  12-15′.

Syringa vulgaris ‘Nadezhda’: Double, lilac-blue flowers.  Mid-season. 8-12′.

Syringa vulgaris ‘Krasavitsa Moscovy’ aka Beauty of Moscow:  Very pale pink buds open to double white flowers.  12′.

Syringa vulgaris ‘Lavender Lady’: Light purple flowers.  12′.

Syringa vulgaris ‘Paul Thirion’:  Reddish-purple buds open to double pale purple flowers.  French lilac.  10-12′.

Syringa x hyacinthiflora ‘Pocahontas’:  Deep purple buds open to paler purple.  Canadian Lilac.  Early.  10′

Syringa vulgaris ‘President Grevy’: Violet-blue, double flowers.  French liac.  10-12′.

Syringa vulgaris ‘President Lincoln’:  Purple-blue flowers.  Mid-season.  8-10′.

Syringa vulgaris ‘Sensation’:  Reddish Purple florets, tinged in white.  French lilac.  Mid-season. 10-12′.


Summersweet

Walking around the nursery yesterday, I couldn’t help but notice the overall lack of color.  With so many deciduous trees on site, you would think we would have a riot of red, purple, orange and yellow leaves all over the place.  Unfortunately, Nantucket’s moderate climate doesn’t usually make for excellent displays of autumn leaves.  Most years, we go from a lush green nursery in September to rows and rows of bare twigs by mid November without much fall color in between.  I couldn’t help but notice a stunning show of yellow from a group of sweetpepperbush (aka summersweet) in the shrub area today, however.  On a dingy autumn afternoon, they really brighten things up.

Clethra alnifolia, as botanists refer to itis a native North American plant that is endemic to Nantucket where it can be found growing in low-lying areas and at the edges of wetlands.  If grown in moist soil, it tends to sucker and form colonies over time.  However, this plant is well-behaved and very adaptable, doing well in most any island garden where average soil and even water is available.  It prefers full sun, but will flower in shade.   The overall look of these plants is a pleasant green, twiggy shrub with an upright, balloon-shaped habit.  They have medium green, rounded, ovate leaves with finely-toothed edges.  In mid summer, they produce loads of fragrant flowers that are reminiscent of small, skinny bottle brushes.  The native form of this plant generally has white flowers, but there are pink cultivars available, as well.  Beneficial insects like it just as much as we do; many species of butterflies, bees, wasps, flies and other flying insects frequent the plant while it is in flower during July and August.

Clethra can serve many uses in the landscape.  If planted in a row, they make a great informal hedge that doesn’t require much pruning to maintain a tight shape.  I’ve seen them used very well in mixed shrub borders with both native and ornamental plants.  They make natural companions to bayberry, arrowwood, groundsel and beach plum, but look just as well among ornamental plants like butterfly bushes, vitex, shrub roses and spiraea. They respond very well to pruning and can be maintained at a height of five feet or so with an annual pruning.  Some gardeners prefer to remove the spent flowers while others leave them on the plant to be covered up by the new growth in spring.

There are many cultivars available in the trade as well as the straight species:

Clethra alnifolia The species form of this shrub.  Generally grows 3-4′ wide and 6 or more feet tall.  White flowers.

‘Anne’s Bouquet’:  White flowers.  Average size.

‘Hummingbird’:  Compact, white-flowered form.  2-4′ wide and up to 5′ high.

‘Pink Spires’:  Pink-flowered form, average size.

‘Ruby Spice’:  Pink flowers, average size.

‘Rosea’:  Pink flowers.  Average size.

‘Sixteen Candles’:  Compact, white-flowered selection with white flowers.

‘Vanilla Spice’:  Proven Winners introduction.  White flowers, touted to be larger than most.  Average size.