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Big-leaved Perennials
Make a bold statement in the sun or shade
by Valerie Easton
from Fine Gardening issue 108
Rodgersia podophylla
Photo/Illustration:
Michelle Gervais
Whenever one of my garden beds or borders appears lusterless, I look to giant
perennials to quickly enliven the scene with architectural style and diversity. Splays of
hefty gunnera leaves or rodgersia foliage provide near-instant gratification. These
bountiful beauties also add depth to plantings. If a design just doesn’t jell, it’s often
because there are too many like tones or similar flower or leaf sizes. To break the
monotony, I throw brawny chocolate ligularia or the fat spires of felty gray mullein into
the mix.
Likewise, plantings that lack textural variation and have too many little leaves end up
looking fussy, overly detailed, and chaotic. Tiny leaves cry out for a generous expanse
of foliage to give contrast to the scene and provide a place for the eye to rest. Just be
sure that the perennials you choose are sizable, featuring leaves that are either
exceptionally long or at least 5 to 6 inches wide. Over time, these botanical giants will
increase in impact as they expand in height and girth.
GIANT LEAVES FOR SUNNY SITES
Verbascum bombyciferum
Photo/Illustration:
Jennifer Benner
Mulleins (Verbascum bombyciferum and cvs., USDA Hardiness Zones 5–9) are one of
the few big-leaved perennials that offer felty gray leaves, reaching 14 inches long. While
all selections of this species are gardenworthy, the largest cultivar, ‘Arctic Summer’, is
one of my favorites. It towers at 8 feet when in bloom and spreads like a candelabra. In
midsummer, golden yellow flowers ignite its tall, silvery spires. It is truly a sight. Mulleins
are a magnificent addition to the garden. Despite their height and branching, they don’t
need staking when grown in their preferred conditions of gravelly or dry, lean soil. These
plants are evergreen and love drought. For a sure hit, pair ‘Arctic Summer’ with bronze
fennel (Foeniculum vulgare‘Purpureum’, Zones 4–9) and euphorbias (Euphorbia spp.
and cvs., Zones 4–11), or grow it at the back of a hot-colored border. Mulleins tend to
be short lived, but do not despair—they seed about obligingly.
Gunnera manicata
Photo/Illustration:
Jennifer Benner
Gunnera (Gunnera manicata, Zones 7–10) is the granddaddy of big-leaved perennials.
No other plant can so thoroughly alter the scale of a garden while calling such attention
to itself. Each thick, hairy, veined leaf grows nearly 5 feet across, and the entire plant
stretches 8 to 10 statuesque feet. It erupts from the ground in springtime, with leaves
unfolding from thick, hairy, pinkish stems. The conelike, greenish red blooms reach 3
feet high as they pop up in early summer. Gunnera is one weird, colossal plant,
intriguing children and adults alike. It requires full sun to partial shade and rich, moist
soil. It is particularly happy at the bottom of a wet slope, along the margins of a stream
or pond, or in bog gardens. It makes a stellar focal point and is always a “big”
conversation piece.
Crambe cordifolia
Photo/Illustration:
Michelle Gervais
Colewort (Crambe cordifolia, Zones 6–9) is the David Copperfield of the plant world. In
full bloom, it’s hard to believe that such cabbagey leaves and thick stems could be
topped with such a sweet-scented halo of tiny, white stars. The blooms float ethereally
above the foliage for weeks in midsummer, and the 14-inch-wide leaves are impressive
all season long. Reaching 3 feet tall and 5 feet wide, mounds of colewort are best used
at the middle or back of a border. This is a stunning addition to an all-white garden. It’s
effective against a background of evergreens or dark-foliaged plants. Colewort is not a
fussy plant. It prefers full sun and fertile soil; it will take partial shade and poorer soil at
the expense of size. Slugs have been known to chomp on this plant’s leaves, so be on
the lookout for these slimy pests as soon as the foliage emerges in spring.
DYNAMIC FOLIAGE FOR PARTIAL SHADE
Rodgersia aesculifolia(left) and Darmera peltata(right)
Photo/Illustration:
Jennifer Benner
Umbrella plant (Darmera peltata, Zones 5–9) loves a partially shady, moist spot in the
garden, where its huge, lily-pad-like leaves can spread. The leaves can reach 24 inches
in diameter and look like something from a fairy tale. This plant is sometimes called
Indian rhubarb because of its showy, pink blooms. The flower spikes emerge from the
ground on naked stems in early spring and are followed by the leaves shortly after.
Clumps can reach 4 feet tall and 3 feet wide. In autumn, the leaves turn red, which is
more intense in sunnier locations. Umbrella plant spreads by rhizomes and can be
aggressive in very moist soil. This characteristic makes it a perfect plant for boggy areas
of the garden, where few plants will grow. If you give umbrella plant average, moist soil,
its exotically large, rounded foliage will lend a tropical air as it comingles with other
perennials in the mixed border.
Rodgersias (Rodgersiaspp. and cvs., Zones 3–8) are one of the most handsome
perennials around with their wonderfully quilted, palmate leaves. There are several
striking species, so it’s hard to go wrong. They generally reach 3 to 6 feet tall and wide.
Their fluffy flower plumes resemble those of astilbes and range in color from white to
pink in mid- to late summer. Rodgersia aesculifolia (Zones 5–8) is an excellent species
with 10- to 12-inch-long leaflets that contribute to each leaf section’s 18- to 24-inch
spread. Rodgersia podophylla (syn. R. japonica, Zones 5–8) has bold, toothed leaves
that reach 16 inches wide and turn a brilliant red in autumn. The oddball of the
group, Rodgersia tabularis(syn. Astilboides tabularis, Zones 5–7), has huge 36-inchwide leaves that resemble lily pads that just floated ashore. While not a water plant, it
does prefer moist, but not water-logged, soil. And like the rest of the clan, it thrives in
partial shade but will take full sun as long as it has a rich, damp place to sink its roots.
Ligularia tussilaginea'Gigantea'
Photo/Illustration:
Steve Aitken
Ligularias (Ligulariaspp. and cvs, Zones 4–8) are another group replete with variation.
With plants ranging from 3 to 6 feet tall and wide, ligularias sport 12- to 14-inch-long
leaves of exaggerated dimension and golden yellow, daisylike flowers in summer. The
most striking plants of the group areLigularia dentata‘Othello’ with deep purplish green,
kidney-shaped leaves; L. przewalskiiwith long, deeply toothed leaves and dark purple
stems; and the new hot plant, Ligularia‘Britt Marie Crawford’, with glossy, chocolatecolored leaves with red reverse. Create a color echo along the border with burgundyleaved perennials like ‘Chocolate Ruffles’ heuchera (Heuchera micrantha‘Chocolate
Ruffles’, Zones 3–8). Ligularias are satisfyingly easy to grow. When protected from slug
predation and given damp soil and partial shade, ligularias stay lush and full from
springtime through frost.
Podophyllum peltatum
Photo/Illustration:
Jennifer Benner
Mayapples (Podophyllumspp., Zones 3–9) have been newly rediscovered by the
gardening world and are coveted for their bold, veined foliage splashed and mottled with
near-black patterning. This distinctive coloration makes their palmlike, lobed leaves
even more dramatic when planted in a damp, semishaded border or woodland garden
where they rise above the soil on tall stems like parasols. The species Podophyllum
peltatum (Zones 3–9) spreads to form an 18-inch-tall by 4-foot-wide clump. It has cupshaped, nine-lobed leaves with waxy, fragrant, pale pink flowers in spring. Podophyllum
hexandrum(Zones 5–8), known as the Himalayan mayapple, has broad leaves notably
mottled in purplish brown. The leaves of both plants spread to 12 to 14 inches in
diameter and look stunning against the fine texture of ferns. Mayapples do best in
partial to full shade and thrive in rich, humus soil.
BOLD LEAVES FOR SHADY NOOKS
Brunnera macrophylla‘Jack Frost’
Photo/Illustration:
Michelle Gervais
Brunnera (Brunnera macrophylla and cvs., Zones 3–7), also commonly known as
Siberian bugloss, is a small-stature perennial that provides a big punch. While the
species sports clean, medium to dark green leaves, there are several variegated
selections that are to die for. ‘Jack Frost’ is one of the best and has hit the ground
running. Its dinner-plate-size, ovate leaves are so veined and splashed in white that
they appear covered in silver. Its tiny, true blue flowers resemble forget-me-nots, and
they bloom early to mix with crocuses (Crocus spp. and cvs., Zones 3–8) and daffodils
(Narcissus spp. and cvs., Zones 3–9). Like its predecessors, ‘Jack Frost’ prefers shade,
where its variegated foliage shows up beautifully. Protect its leaves from slugs, and
enjoy it as an edging plant along a woodland border, where it will reach 18 inches tall
and 24 inches wide. Unlike many other large-leaved plants, Brunneraspecies are
drought tolerant once established.
Hosta‘Sum and Substance’
Photo/Illustration:
Jennifer Benner
Hostas (Hostacvs., Zones 3–9) are the quintessential foliage perennial. They come in
all sorts of shapes, sizes, and colors, several of which fit the bill when a design calls for
giant leaves. ‘Sum and Substance’ is one of the biggest and the brightest. It easily
forms a 4-foot-wide clump, with each heart-shaped chartreuse leaf spanning 20 inches.
It is truly hypnotic as it expands into a wide puddle of sunshine in a shady border,
lighting up the garden from spring to frost. Although the leaves steal the show, ‘Sum
and Substance’ does send up pale lilac flowers in late summer. For dramatic color
contrast, consider placing Hosta‘Ryan’s Big One’ nearby. It is another giant hosta that
forms a 5-foot-wide clump of glaucous, puckered, 18-inch-long leaves and produces
white flowers in late spring. As with all hostas, give these big guys moist, fertile, welldrained soil in a spot with partial to full shade and mind any slugs that come along.
KEEPING BEAUTY FROM BECOMING A BEAST
Photo/Illustration:
Jennifer Benner
Whether you’re beginning a new garden or tweaking an old one, you can add
architectural scale and beauty by selecting perennials that grow large. Keep in mind,
however, that anything so luxuriant will, of course, outgrow its bounds—no doubt sooner
than you intend. Perennials never spread to a certain point and then stop. Nature in its
abundant vigor isn’t like that. So be prepared to give over plenty of space to these
garden racehorses, or keep your spade and clippers handy to keep them under control.
That’s not to say you should shy away from these plants in small spaces. It’s even more
important to vary the scale of the plantings to add depth and intrigue to cramped
quarters. Surprisingly, large-leaved plants make small gardens appear larger, in part
because they obscure what’s just around the corner.
Petasites japonicus
Photo/Illustration:
Melissa Lucas
Petasites japonicus (Zones 5–9), commonly calledbutterbur or coltsfoot, is a jawdropping, 50-mph plant. Its monstrous 32-inch-wide, kidney-shaped leaves cover its
huge, 40-inch-tall by 60-inch-wide mounding habit. In early spring, before its leaves
arrive, butterbur has stalks topped with tightly clustered, yellow-green flowers. This
perennial often needs no companions; it looks good in stands all alone. The variegated
form,Petasites japonicusvar. giganteus‘Variegata’, is especially showy, with fragrant
flowers and 3-feet-wide, white-edged leaves. Butterbur likes very rich, moist soil in
partial to full shade. It’s not for everyone, though; it tends to spread aggressively in wet
soil, which may not be a problem if you have a damp, shady spot to fill.
It is said of perennials that in their first year they sleep, in their second they creep, in
their third they leap. But most of the plants mentioned here take fewer than three years
to show their stuff. Prepare the soil with generous additions of compost, top-dress with a
little well-composted manure, water until established, and stand back. These plants will
be living large before long, adding architecture and textural variation to your garden.