Plants for Tiny Gardens

Credit: Great Plant Picks

Acer circinatum Athyrium niponicum var. pictum Helictotrichon sempervirens ‘Blue Oat Grass’ Corylopsis pauciflora Crambe maritima Disanthus cercidifolius Cornus kousa var. chinensis ‘Milky Way’ Dryopteris erythrosora Ekianthus campanulatus ‘Red Bells’ Fothergilla gardenii ‘Mount Airy’ Hydrangea quercifolia ‘Snow Queen’ Hydrangea serrata ‘Beni-Gaku’ Osmanthus heterophyllus ‘Goshiki’ Agastache ‘Blue Fortune’ Pieris japonica ‘Cavatine’ Euphorbia characias subsp. wulfenii Nandina domestica ‘Gulf Stream’ Parahebe perfoliata

Planning, plotting, purchasing and planting are followed by perfecting. Sometimes it feels like I have acres to look after, but this, for me, is a pleasure. Some small-space gardeners are unsure of how to approach their gardens. Using tried-and-true Great Plant Picks is a way to choose plants with confidence. And how to put them together? Here are a few “recipes”—from simple to tricky—for small-space gardens.

Easy and Elegant

Buxus sempervirens ‘Suffruticosa’

The owner of this garden may be a young person in their first condominium or retired person eager to travel and relax a bit. Since most small gardens are defined by straight walks or fences, this plan plays off those lines. The beds are edged with dwarf boxwood (Buxus sempervirens‘Suffruticosa’) planted every 40 cm (15 in.). For height, add an always-elegant mountain hemlock (Tsuga mertensiana). It thrives in full sun or part shade and reaches 3 m (10 ft.) tall and 1.2 to 1.8 m (4 to 6 ft.) wide in 10 years. I especially like the dark-green, textured foliage of this B.C. native. Plant this tree about one-third in from the end of the bed, rather than in the middle—otherwise formality might slip into stiffness. Complete this framework with shrubs having compact habits and larger leaves. The following suggestions thrive in full sun or part shade:

• Goshiki means “five-coloured” in Japanese – a hint as to the eye-catching leaves of this cultivar of variegated false holly (Osmanthus heterophyllus ‘Goshiki’). Cream, pink, orange, yellow and white appear through the season on the foliage of this very slow-growing evergreen shrub.
• Oakleaf hydrangea (Hydrangea quercifolia ‘Snow Queen’) has upright clusters of white flowers in mid-summer. The blooms fade to rose-pink and the oak-shaped leaves turn wine-red in autumn.
• Pieris japonica ‘Cavatine’ is a compact form of lily-of-the-valley shrub. It has dark-green leaves and pretty, pale-green flower buds that decorate the plant all winter. The buds open to creamy-white flowers in March.

If your space is shady, add Camellia x williamsii ‘Donation’ for large pink flowers in March and glossy evergreen leaves year-round. If you have sun, plant heavenly bamboo (Nandina domestica ‘Gulf Stream’) for its interesting compound leaf that gives the effect of bamboo without the worries. ‘Gulf Stream’ has bronze new growth in full sun. The simplicity of this limited-palette composition will provide an easily maintained garden that looks good all year. The only care required is watering—especially until the plants become established—an annual dose of all-purpose fertilizer, and trimming the boxwood hedge.

Pint-sized Woodland

For the gardener who craves a more extensive plant collection, the first decision to make is whether the garden is primarily sunny or shady. The next step is to choose a group of plants that relate aesthetically. This way, even a varied planting won’t look disjointed. For shade, the natural theme is a woodland garden. Anchor the planting with an understory tree—one that normally grows in the shade of larger forest trees. Examples include Chinese dogwood (Cornus kousa var. chinensis ‘Milky Way’), our native vine maple (Acer circinatum) or redbud hazel (Disanthus cercidifolius). All three have an attractive branching pattern and stunning fall colour. The dogwood also bears creamy-green flower bracts in June, followed by strawberry-like fruits in late summer. (My dog likes the taste of these and tidies up my entry path.) The next task is to choose a handful of small shrubs that like part shade. Consider the following deciduous shrubs:

• Buttercup winter hazel (Corylopsis pauciflora): yellow flowers in late winter and yellow fall colour.
• Enkianthus campanulatus ‘Red Bells’: red flowers in spring and red-to-orange fall colour.
• Witch alder (Fothergilla gardenii or F. ‘Mount Airy’): fragrant white bottlebrush blooms in late spring and red-to-purple fall colour.
• The inflorescence of mountain hydrangea (Hydrangea serrata ‘Beni-Gaku’) has rainbow hues. ‘Beni Gaku’ is a lacecap hydrangea. Its inner, fertile florets open purple and age to light blue, while the outer, sterile (but showier) florets emerge white and darken to pink with red edges.
• Royal azalea (Rhododendron schlippenbachii): lovely, fragrant, pale-pink flowers in spring and vivid foliage in autumn.

For winter interest, add some evergreen shrubs. The camellia, lily-of-the-valley shrub and variegated false holly mentioned above would work well. For showier blossoms in spring, try one of the many GPP rhododendrons, such as ‘Odee Wright’ or ‘Grace Seabrook’. Another three dozen are shown on the web at www.greatplantpicks.org All have been chosen for their resistance to root weevil damage. For a shady garden, avoid those that are sun tolerant, as they tend to bloom less in the shade. The floor of your mini-woodland can be filled with shade-loving perennials. I am particularly fond of ferns and especially like those that are evergreen: deer fern (Blechnum spicant), Japanese painted fern (Athyrium niponicum var. pictum), autumn fern (Dryopteris erythrosora) and Wallich’s wood fern (D. wallichiana). One fern that never fails to draw a comment is soft shield fern (Polystichum setiferum Divisilobum Group). Its finely cut fronds appear to whirl around its centre like a tornado!

Mini Mediterranean

I recently attended a workshop given by nurseryman Maurice Horn of Joy Creek Nursery near Portland, Oregon. Maurice is working with a technique that involves copious amounts of gravel, and his slides showing bountiful plantings in the most horrific sites (he refers to parking strips as “hell-strips”) speak for his successes. In clay-based soils, he incorporates up to about 20 cm (8 in.) of gravel into the top 45 cm (18 in.) of soil, to guarantee good drainage. This would not be required in sandy soils. The trick, however, is to use gravel as a mulch. Bark mulches gradually break down and plants root into this medium, whereas with gravel mulches the plants keep their roots well below the surface. Plants that tend to flop in a well-watered and fertilized garden bed remain sturdy in Maurice’s gravel beds. If you have a sunny area, you can create the look of a Mediterranean garden. I’ve had good luck with such sun-loving plants as hybrid hyssop (Agastache ‘Blue Fortune’), sea kale (Crambe maritima), large Mediterranean spurge (Euphorbia characias subsp. wulfenii), blue oat grass (Helictotrichon sempervirens), Russian sage (Perovskia atriplicifolia), Penstemon ‘Blackbird’ and sticky Jerusalem sage (Phlomis russeliana). I especially like the oddball appearance of digger’s speedwell (Parahebe perfoliata). Its foliage looks like that of Eucalyptus, but it is related to Veronica and produces beautiful deep-blue flower spikes for a long period in summer.

Plant Collector’s Garden

I am currently undertaking an exercise to see how many plants I can put into a very small garden around a sunny patio. At intervals up from the ground, I attached screw eyes to the surrounding wooden fence. Through these I threaded tiers of clear-plastic-coated wire, attached to the final screw eye with a turnbuckle to tighten the whole works. Growing beneath this arrangement are a number of plants to espalier; some, like oakleaf hydrangea, I’ve never seen as an espalier but what the heck! Instead of choosing compact shrubs to add to my garden, I am deliberately choosing ones with a willowy shape, so they can intermingle with their neighbours. I’m treating this like a cocktail party rather than a sit-down dinner: you can entertain more people at a cocktail party, and the interaction between participants is unpredictable. I’ll let you know how it works out. With more than 30 years experience in horticulture in B.C.—in wholesale, retail and at VanDusen Botanical Garden for a decade—Carolyn Jones brings a wealth of knowledge and expertise to GardenWise and www.gardenwiseonline.ca as staff horticulturist. The following plants are hardy to the zone number indicated: Easy and Elegant Design: Buxus sempervirens ‘Suffruticosa’ (dwarf boxwood) – zone 5 • Camellia x williamsii ‘Donation’ – zone 7• Hydrangea quercifolia ‘Snow Queen’ (oakleaf hydrangea) – zone 5 • Nandina domestica ‘Gulf Stream’ (heavenly bamboo) – zone 6 • Osmanthus heterophyllus ‘Goshiki’ (variegated false holly) – zone 6 • Pieris japonica ‘Cavatine’ (lily-of-the-valley shrub) – zone 6 • Tsuga mertensiana (mountain hemlock) – zone 5 • Pint-sized Woodland: Acer circinatum (vine maple) – zone 5 • Cornus kousa var. chinensis ‘Milky Way’ (dogwood) – zone 6 • Corylopsis pauciflora (buttercup winter hazel) – zone 5 • Disanthus cercidifolius (redbud hazel) – zone 5 • Enkianthus campanulatus ‘Red Bells’ – zone 6 • Fothergilla gardenii (zone 5) or F. ‘Mount Airy’ (witch alder) – zone 4 • Hydrangea serrata ‘Beni-Gaku’ (mountain hydrangea) – zone 6 • Rhododendron schlippenbachii (royal azalea) – zone 5 • Mini Mediterranean: Agastache ‘Blue Fortune’ (hyssop) – zone 6 • Crambe maritima (sea kale) – zone 6 • Euphorbia characias subsp. wulfenii (large Mediterranean spurge) – zone 7 • Helictotrichon sempervirens (blue oat grass) – zone 6 • Parahebe perfoliata (digger’s speedwell) – zone 7 • Penstemon ‘Blackbird’ – zone 6 • Perovskia atriplicifolia (Russian sage) – zone 5 • Phlomis russeliana (sticky Jerusalem sage) – zone 4