Sustainable Options for the Boxwood Blues – Half 2 – Halton Area Grasp Gardeners

Pam MacDonald – Halton Grasp Gardener

Cowl Picture: Baptisia australis (blue false indigo) one of many attainable choices for these changing boxwood.

Within the September difficulty of Cross Pollination, the use and decline of boxwoods was mentioned. Gardeners not prepared to surrender on their boxwoods have been provided steerage and pointed to different sources of knowledge on coping with one of many new points afflicting boxwoods – the Field Tree Moth.

As Grasp Gardeners, our focus is on sustainable, environmentally pleasant gardening practices. With this in thoughts, we encourage gardeners who’ve determined to interchange their boxwood to contemplate native species.

On this article we describe native vegetation we think about good options to boxwood, vegetation that bridge the hole between what gardeners need and what wildlife wants. We embrace native evergreen and deciduous shrubs. Our deciduous suggestions might lose their foliage in winter however they make up for it with different aesthetic and ecological contributions to the panorama.

We additionally embrace some herbaceous native vegetation with a shrubby look. Why would we embrace these? Consider the problem of clearing snow from driveways or sidewalks hemmed in by woody shrubs or the injury performed to boxwoods by salt. Our herbaceous strategies get rid of these issues. They die again in winter and two of the vegetation we recommend are salt tolerant.

Boxwood is suited to a broad vary of situations which has been a part of its enchantment. Substitutes could also be extra particular of their necessities. For instance, vegetation that decision for full solar won’t have dense foliage if located in shade. The foliage of vegetation that want persistently moist soil, if situated on dry websites, might discolour and the plant might defoliate. When selecting your boxwood substitute, do not forget that placing the appropriate plant in the appropriate place is significant to a cheerful resolution to the Boxwood Blues.

All of our urged native vegetation can be found at native plant nurseries. Some are additionally accessible at backyard centres. We encourage you to learn our companion article Bee an knowledgeable and glad client – and gardener earlier than you finalize your selections about what vegetation to purchase and the place to purchase them.

Ilex glabra (inkberry holly)

Inkberry holly ‘Gem Field’ (Picture: Piedmont Grasp Gardeners)

Inkberry holly is an evergreen holly native to Jap North America. In its pure habitat, inkberry holly grows to 10 ft in peak and is normally present in moist areas like swamps and bogs. These solar loving vegetation want moist soil; nonetheless, they’re adaptable and can do effectively in common backyard soil supplied they’re effectively watered whereas they’re getting established. Like most different hollies, inkberry is dioecious. Not like the holly we affiliate with Christmas, the leaves of inkberry should not have sharp thorn-like spines.

There are a number of alternatives of a chilly hardy Inkberry native to the maritime provinces and jap United States suited to the local weather of southern Ontario. These alternatives are extra compact than the species. There are additionally two dwarf cultivars which were bred to imitate the looks of boxwood.

Relying on the species of inkberry, the berries could also be purple, black, orange, or yellow. The berries add winter curiosity and are a meals supply on the finish of winter for hungry birds. These dense shrubs additionally present good winter cowl for wildlife. Fortunately, inkberry shouldn’t be a primary alternative of deer to browse and it isn’t engaging to rabbits.

The berries, for each aesthetic and ecological causes are highlighted when inkberry is marketed. Bear in mind that the listed alternatives are all feminine and the one confirmed male wanted for fertilizing them, ‘Fairly Boy’ shouldn’t be all the time accessible.

Ilex verticillata (winterberry holly)

‘Berry Poppins’ in summer season. (Pictures: Arbour Day Basis)

'Berry Poppins' in winter. Image: Arbour Day Foundation — ‘Berry Poppins’ in winter.

Winterberry is a multi stemmed deciduous holly native to all of jap half of North America.

Within the wild it’s usually present in bogs and swamps the place it varieties massive colonies of open, sparsely branched shrubs 10 to fifteen ft tall.

In drier soils present in managed landscapes, it’s a considerably shorter, dense shrub with an upright to rounded form . It could actually stand up to some pruning and the most effective time for that is early spring, earlier than new development emerges. It will reduce discount in berry manufacturing the next fall.

Winterberry thrives in full solar. Partly shade, it is going to be leggy and produce fewer berries .It prefers persistently moist soil however can tolerate each poorly drained and dry soils.

Like different hollies it’s dioecious. The really helpful ratio for greatest berry manufacturing is one male plant to fertilize as much as six feminine vegetation.

The profusion of sensible purple berries on these shrubs from fall by to late winter, greater than compensates for the dearth of winter greenery. On a snowy winter day, a hedge or mass planting is a panoramic sight.

It’s extensively utilized in restoration initiatives for erosion management and for its advantages to wildlife. It attracts greater than 40 species of birds. The extremely decorative berries are additionally appreciated by birds as a supply of late winter meals. It additionally offers cowl from predators and nesting websites.

There are additionally many cultivars, too quite a few to listing right here….

Ceanothus americanus (New Jersey tea)

New Jersey tea is a troublesome, compact plant that thrives in scorching, dry, sunny areas. It’s adaptable, rising in a variety of soils and partially shade in addition to full solar. As soon as established, New Jersey tea, will tolerate harsh environments. It’s nonetheless illiberal of poorly drained, soggy soils the place it’s weak to root rot.

This shrub typically tops out at 3 ft and is wider than it’s tall. It tends to sucker however not aggressively. The suckers might be eliminated or left to fill in area when it’s getting used for a hedge or mass planting. New Jersey tea will attain its most peak and may develop right into a dense low hedge in two or three years.

This shrub is especially helpful for low hedges close to driveways and facet walks. It won’t obscure sightlines and it tolerates drought, wind and salt attributable to its deep, robust roots. Additionally it is a wonderful alternative to interchange boxwood for framing a parterre-style backyard.

The fragile white flowers of New Jersey tea are aromatic and lengthy lasting. It blooms in late spring into summer season. Within the first two seasons when it’s small, remember to shield it from looking by rabbits with a {hardware} material cylinder. It responds effectively to an early spring prune to form and take away any useless branches.

New Jersey tea additionally has nice ecological worth. It’s a nitrogen-fixing plant, a larval host plant for a number of butterflies and nectar supply for bees. No surprise it was chosen North Carolina Wildflower of the Yr method again in 2013.

Symphoricarpos albus (widespread snowberry)

Frequent Snowberry (Picture: Oregon State)

Snowberry is a fairly, delicate-looking shrub that was adopted by settlers and was widespread in ‘quaint’ Canadian gardens till at the least the 1950’s. Gardeners of a sure age might recall snowberry from their childhood.

It’s a versatile shrub that may develop in solar, half or full shade. It tolerates poor high quality soils and a spread of moisture from dry to moist. So as to add to its old school virtues, snowberry is immune to drought, air pollution and salt.

Sparsely branched, this shrub is airier than boxwood and different substitutes we now have urged. It’s appropriate for hedging to delineate areas however won’t make a dense privateness hedge. It can develop in full shade however could also be too sparse to be of worth as a panorama plant on this state of affairs. The peak and form of snowberry might be managed with common mild pruning. That is greatest performed in late winter/early spring to keep away from eradicating flower buds and the resultant berries.

The brilliant white berries are luminous towards the richly colored foliage and persist into late winter.

As a peek-a-boo hedge described above, or en masse as a tall floor cowl in tough areas, it’s rather more attention-grabbing than a strong mass of inexperienced.

In late winter, when meals is scarce, many species of birds hunt down the berries of this and different vegetation we now have urged. Although the flowers of snowberry are ornamentally insignificant, hummingbirds and bees are drawn to the nectar.

Hypericum kalmianum (Kalm’s St Johns wort)

Kalm’s St John’s wort is a local of the good lakes’ area, discovered alongside sandy and typically rocky shores of Lake Huron and Lake Michigan. Rising within the wild it could be a sparse shrub, not more than a foot or two tall. In managed landscapes it would sometimes develop right into a dense mound, 2-3 ft tall. It thrives in full solar and moist to dry, mild textured soils. Kalm’s St Johns wort will tolerate half shade however will probably be a looser, extra open shrub with fewer flowers.

This shrub is a stunner with fine-textured blue-green foliage and much of lemon-yellow flowers in summer season. Bumble bees gravitate to this plant for its pollen. They eat the pollen for the protein they want and queens use it to make beebread to feed their offspring. Deer and rabbits, fortunately have little curiosity in St John’s wort.

Kalm’s profit from a light-weight pruning after blooming to keep up the dimensions and form of the shrub. Because it flowers on new wooden, pruning is greatest performed instantly after the present 12 months’s flowers fade to keep away from eradicating any of subsequent 12 months’s flower buds.

Shrubby St John’s wort is one other species of Hypericum present in Ontario,. It’s much less refined although equally deserving of a spot in a sunny backyard.

Symphyotrichum oblongifolium (fragrant aster)

Fragrant Aster (Picture: Missouri Botanical Backyard)

This can be a compact aster that’s as interesting to bees and butterflies as it’s to our eyes. If planted close to the entrance of the border, passersby will probably be questioning what it’s, with its aromatic, diminutive foliage. When the flowers start to open in late summer season, it’s a ‘stop-the-car’ type of plant. It’s completely lined in blooms over an extended interval. Whereas missing any winter curiosity, it makes up for it in early spring, sprouting up right into a mound. Because it settles into your backyard, it is going to be wider, than tall—creating a lovely rhythm significantly in a sloped backyard. Fragrant aster shouldn’t be native to Ontario however is widespread within the Midwest and northeastern US. Don’t fear, it’s fairly hardy for zone 6 in Ontario.

This plant can take robust situations, however don’t place it in moist soil the place the stems will get floppy. Full solar, part-sun, clay, sandy or rocky soil aren’t any drawback in any respect.

To maintain the dimensions compact, pinch it again twice in mid to late spring, depending on the expansion.

Baptisia australis (wild blue indigo)

Although the native vary of this plant doesn’t embrace Ontario and its time and mode of migration right here unclear, it’s helpful to Ontario wildlife and grows effectively with native vegetation. Perhaps it slipped throughout the border on the Underground Railway or with the Empire Loyalists!

wild blue indigo (Picture: Claudette Sims)

Wild blue indigo thrives in full solar in effectively drained soils. Partly shade it would develop into floppy.

For the primary 12 months or two, this plant could have few stems and no flowers. It’s busy placing down a deep faucet root that may set it as much as thrive in scorching dry situations and tolerate harsh environments. As a mature plant, it would rise every spring from its woody base to kind a vase formed mound of blue-green leaves topped with spires of blue, candy pea-like flowers. Wild Blue Indigo maintains a satisfying form after flowering and might be trimmed as wanted to keep up the specified measurement till the plant goes dormant within the fall.

Like different members of the pea household, to which it belongs, Wild Blue Indigo is nitrogen-fixing and can add nitrogen to the soil because it grows. Its early blooms are a welcome supply of nectar for queen bumblebees waking from winter hibernation. Additionally it is a larval host to a number of species of butterflies and moths.

Thuja Occidentalis (white cedar)

White Cedar ‘Golden Globe’ (Picture: NC State Extension)

Thuja occidentalis, higher often called jap white cedar, is an evergreen tree native to Jap North America. One other identify for Thuja is arborvitae which suggests “tree of life’. ‘Emerald’ Jap white cedar are ubiquitous hedges and privateness screens. Many hen species admire the shelter and nesting websites these timber present.

There are many compact and dwarf Thuja cultivars. They bear little resemblance to the species. They’ve been bred to fill the demand for smaller evergreens, nonetheless within the course of they’ve misplaced their ecological worth.

Seek the advice of the hooked up desk for some domestically accessible Thuja occidentalis cultivars.

All of those cultivars want full solar and moist to medium soil. They’re all gradual rising. Nonetheless, when planting any of them, take note the mature measurement. As with boxwood, common mild pruning will guarantee they preserve their form. The exception is ‘Mr. Bowling Ball’ which requires no pruning to keep up its form.

Taxus (yew)

Japanese yew ‘Nana” (Picture: North Carolina Extension)

Whereas there’s a Taxus species (Taxus canadensis) native to Ontario, it’s a low groundcover and at this time limit not extensively accessible within the horticulture commerce. The yews appropriate for changing boxwood in our area are non-native species. Probably the most appropriate of those, as a substitute for boxwood, is Taxus cupidata ‘Nana’ Dwarf Japanese Yew.

Yews develop in solar or shade, preferring barely acidic, effectively drained soils. They’re illiberal of moist, poorly drained soils which is able to result in root rot. They are often pruned to regulate measurement and form. Early spring is the most effective time for pruning.

Itea virginica (Virginia sweetspire)

Virginia Sweetspire Hedge ‘Little Henry’ (Picture: George Weigel)

Itea is an adaptable shrub from south of the Nice Lakes that provides stunning texture, aromatic spring flowers and fall color, whereas on the identical time being a supply of nectar in spring.

Whereas the species prefers acidic, moist soil and partial shade, the cultivars can thrive in clay, sandy soil and full solar if supplied sufficient moisture to develop into established in your backyard. The slender, arching branches present stunning texture and the foliage turns to a vivid purple to maroon color in autumn. Whereas virtually the ‘good’ shrub as an accent, border or basis planting, it does have one downside. It tends to sucker. The suckers emerge from the basis system and may develop right into a colony over time if not eliminated as they seem. Suckering is extra widespread in wealthy soils reasonably than dryer, heavy soils.

The cultivars supply a extra compact shrub and typically variation in leaf tone and fall color. If grown in full solar, this plant will develop a extra dense construction than an space with much less mild. Did I point out that it’s additionally deer resistant and drought tolerant as soon as established?

BOXWOOD ALTERNATIVES

PLANTS	TYPE Ev – Evergreen D-deciduous HP-herbaceous perennial	ORIGIN N-Native Nn Close to Native NC Native cultivar EX-exotic	SIZE	CONDITIONS	FEATURES	CARE	USES
*1. Ilex glabra* Inkberry Holly ‘Shamrock’ ‘Gem Field’ ‘Strongbox’ ‘Compacta’	Ev	Nn	80-100 cm h. 80-100 cm w. *dependent on cultivar	Solar to Pt. Solar avg. to moist acidic	Evergreen Salt tolerant Dense, darkish inexperienced foliage Black berries add winter curiosity Cowl and nesting for birds Birds eat berries is current	Water effectively till established Pruning really helpful.	Basis, hedge
*2. Ilex Verticillata* Winterberry Holly ‘Berry Poppins’ (’Mr. Poppins’) wide selection of cultivars	D	N NC	80cm – 200 cm h. 80cm – 200 cm w. *depending on cultivar	solar dry to moist adaptable to most soils	Enticing foliage turns yellow, typically maroon, in fall Vivid purple berries add winter curiosity Erosion management, meals and shelter for birds Tolerates poorly drained soil, clay, air air pollution	Winterberry is dioecious You’ll want to plant a male shrub from the identical ‘group’ inside 15 m of the feminine shrubs (i.e. Mr. Poppins).	Rain gardens, hedges, basis plantings
*3. Ceanothus* *americanus* New Jersey Tea	D	N	1 m h. 1 m w.	solar to pt. solar dry, common adaptable to most soil situations, however keep away from poorly drained websites	Vivid inexperienced leaves, dense mounding kind aromatic clusters of small white flowers in summer season Erosion management Nitrogen fixing Larval host to butterflies Nectar sources for bees *Tolerant of drought, salt & wind	Shield for first few years from looking by rabbits with {hardware} material cylinder Prune early spring to form and take away useless branches	Butterfly host plant massing low hedge
*4. Symphyocarpos albus* Frequent Snowberry	D	N	125-150 cm h. 100-150 cm w.	solar, pt. solar to shade dry to common adaptable to most soil situations	Grows shortly in some websites Blue-green, clean oval leaves Summer time flowering Clusters of tiny pinkish white flowers in summer season adopted by vivid white berries Winter meals for birds Nectar for bees and hummingbirds Larval host plant Tolerant of: drought, air pollution, salt and poor high quality soil	Grows greatest in a sheltered location Gentle pruning to form in late winter/ early spring.	Hedge, mass planting, combined shrub border
*5. Hypericum* *kalmianum* Kalm’s St Johns wort (Pot -o-Gold, Aaron’s Beard)	D	N	60 – 100 cm h. 60-100 cm w.	solar to pt. solar dry, well-drained sandy soil	Pollen is a supply of protein for mature bumble bees and their larvae Drought tolerant and reasonably salt tolerant *Attracts butterflies	Prune to advertise subsequent 12 months’s flowers, preserve form Might have a clean-up of die-back in early spring	Low hedge, combined shrub borders, basis planting
6. Symphyotrichum *oblongifolium* Fragrant Aster	HP	Nn	30-100 cm h. 60 – 100 cm w. depending on cultivar	solar to pt. solar dry to moist well-drained sandy, rocky, clay	Aromatic delicate mounded form bursts with blue/purple blooms early fall in zone 6 engaging to bees and butterflies tolerant of drought and poor soil, deer and rabbits	Lower/pinch again 1/3 of the foliage twice earlier than early summer season, to keep up form and foliage vigour	Floor cowl mass planting combined shrub border
*7. Baptisia australis* Wild Blue Indigo	HP	N	1.2 m h. 1.2 m w.	solar to pt. solar dry, common, moist well-drained	Quick, reaches mature measurement and flowering in 2-3 years Effective textured blue-green foliage, showy flowers Nitrogen fixing, Tolerant of drought & salt	Water to ascertain Prune to keep up measurement and form after flowering	Low hedge, combined shrub borders, basis planting
*8. Thuja* *Occidentalis* *‘Danica’,* *‘Little Teddy’, ‘Mr. Bowling Ball’, ‘Little Big’*	Ev	NC	0.5-1 m h. 0.5-1 m w. *depending on cultivar	solar, to pt. solar moist to moist well-drained	Depending on cultivar foliage varies: blue, inexperienced or gold Threadlike, lacy, feathery or scale-like foliage Some cultivars change to a bronze color in autumn Illiberal of salt, dry/drought situations	Prune to form after new development emerges (mid-spring) Many cultivars want afternoon shade *If in uncovered location, shield with burlap display	Hedges, basis planting, specimen, formal backyard
9. Taxus Cuspidata ‘Aurescens’ ‘Nana’ Taxus x Media ‘Hillii’	Ev	EX	100-125 cm h. 125-175 cm w.	solar to pt. solar dry, common to moist well-drained	Feminine vegetation have a fleshy, purple aril New development on ‘Aurescens’ cultivar are golden, contrasting with older inexperienced foliage *Sluggish-growing	Prune to form if desired Shield from drying winds in uncovered areas All plant components (besides fleshy a part of the fruit) are toxic (together with the seed within the fruit) Root rot can happen on moist websites	Border, hedge, basis planting, topiary
10. Itea virginica Sweetspire ‘Little Henry’ ‘Saturnalia’ ‘Merlot’	D	Nn, C	1-2 m & w. for species 50-125 cm h & w for cultivars	Full solar, pt. solar, shade dry, common to moist well-drained	Aromatic slender panicles in spring flowers present nectar for bees stunning fall color slender arching branches	Might must take away suckers to acquire desired form	Specimen, hedge, basis, mass planting, rain backyard, erosion management