3 Hardy Plants with Umbrella Leaves

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The peltate leaf of Astilboides tabularis.

Round, umbrellalike leaves are pretty rare in the wild, even more so in temperate climates. They share a curious leaf shape: a petiole fixed right in the center of the leaf, on its underside, much like a shield. The botanical term for these leaves is “peltate”… but I bet the average gardener would probably instead say they have umbrella leaves, because they do look so much like an umbrella or parasol.

There are quite a few umbrella plants that grow in tropical climates, but three really stand out when it comes to temperate gardens: astilboides, darmera and Japanese butterbur or fuki. Because of their large size, you could almost use any of them as an umbrella!

Although each of these plants is actually quite different, gardeners often confuse them. Here’s how to tell them apart:

Astilboides
Astilboides tabularis

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The huge table-shaped leaves and fuzzy white blooms of Astilboides tabularis.

I’ve sometimes seen the name shield-leaf or shield-leaf rodgersia used for this plant (it used to be called Rodgersia tabularis), but only in publications. Gardeners who grow it all seem to call it by its botanical name, astilboides. So if you want to make yourself understood, therefore, learn to pronounce it. It’s not that hard: a-stil-BOY-dees.

Of the three hardy umbrella plants, this is the one that could be most easily used as an actual umbrella, because its leaves are not only large (up to 3 ft/90 cm in diameter), but almost perfectly round, exactly like an umbrella. The leaves are toothed along the edges,  rather pale green in color and a bit fuzzy to the touch, which gives them a matte texture. The petiole (stem) can easily reach 3 feet (90 cm) tall. The epithet tabularis means table, nicely describing the leaf’s shape.

As for the genus name, Astilboides, it means “looks like an astilbe”, a reference to the fluffy white flowers borne on 4- to 5-foot stems (1,2-1,5 m) that do indeed look like astilbe (Astilbe) blooms. The flowers, produced in June and early July, are however definitely secondary to the foliage where garden impact is concerned.

The plant usually grows as a single clump from a short, thick rhizome. Despite its stalwart appearance, astilboides is actually the trickiest of the three umbrella plants to grow well. To succeed, it needs a moist location and protection from the wind, preferably in partial shade.

For the largest possible leaves, give it a rich, humusy soil that never dries out. It will “hang on” under normal garden conditions, but tends to shrink in size over time if you let it dry out too often. A thick mulch and regular waterings will keep it happiest. It is very slow to spread and, in fact, in most gardens, it will pretty much stay where you plant it. Only under somewhat swampy, shady conditions will it eventually spread to the point where you may need to control it and even then it can take decades to reach that size.

As with all the plants presented here, it’s a hardy perennial, surviving well into zone 3. It is best in cool summer areas, usually zone 7 or less.

Darmera or Umbrella Plant
Darmera peltata (Peltiphyllum peltata)

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Darmera peltata

Smaller than astilboides, to which they are very distantly related (both are in the Saxifrage family), darmeras have leaves that are very similar in shape, although considerably smaller. The nearly round leaf with toothed edges is peltate (its petiole is fixed to the underside of the leaf near its center), hence the epithet peltata.

Typically the leaf measures about 1 foot (30 cm in diameter), but can be twice as large in a sufficiently moist environment. It is slightly reddish in the spring, then medium green in summer, and takes various red hues in fall when it is perhaps at its most beautiful. Unlike astilboides leaves, with their fuzzy matte texture, darmera leaves are smooth and shiny.

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Rhizomes of Darmera peltata in earliest spring.

The leaves grow individually from a creeping rhizome. In the wild, the rhizome grows partially exposed, but is often out of sight under a layer of mulch in home gardens. Although it may be a bit slow to get started, darmeras are more robust plants than astilboides under most garden conditions and eventually form quite a colony. They are not really invasive (their progress is too slow to meet that definition!), but they will keep spreading if you don’t stop them. You can control their expansion with an ax or shovel if ever they go too far. Their dense roots makes them an excellent choice for erosion control along rivers and lakes.

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Darmera peltata blooms without foliage on stems of varying height.

Darmeras have very unusual blooms. They appear in early in the spring, well before the leaves, on erect purplish stems of variable height. You’ll see them blooming on 1-foot (30 cm) stems and up to 5-feet (150 cm) ones under the same conditions! The stem is topped by a dome of five-petaled flowers in various shades of pink or, very rarely white, always with a darker pink center. Altogether this makes them look vaguely like a fairytale mushroom appearance: one almost expects to see little smurfs setting up shop at their base.

As with astilboides, darmeras prefers damp to moist soils, but are even more comfortable in soggy areas than the former. Indeed, they’ll grow with their rhizomes slightly covered in water. They’re a good choice for sites that are flooded in the spring, but drier in the summer. They do like moisture though: not necessarily soggy soils, but ones that remain a bit moist at all times, such as those at the bottom of a slope, in a depression, or at the edge of a water garden. They do fine enough in more typical “barely moist” garden soils, but their leaves remain smaller under those conditions. Mulch them profusely in such a situation and water it if possible in times of drought.

You can grow darmeras in full sun (as long as the soil is always moist) or in deep shade. In the latter case, it will want a spot that gets some spring sun. Most gardeners will find they do best in partial shade.

Finally darmeras are much hardier than they are usually given credit for. A lot of sources say zone 4 or 5, yet I’ve seem superb colonies of D. peltata that that have thrived in zone 2 for decades! As with the other plants described here, it is mostly a cool-climate plant, for zone 7 or less.

Japanese Butterbur or Fuki
Petasites japonica

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Huge leaves like a tractor seat define Japanese butterbur.

The leaves of Japanese butterbur are not really round, but rather kidney-shaped, nor is the leaf truly peltate. Instead the petiole is attached to the top of the leaf. Even so, people get it confused with the two previous umbrella plants. To readily distinguish it from either astilboides or darmeras, remember that its leaves are shaped like a tractor seat rather than an umbrella.

And leaves can be huge, measuring up to 30 inches (80 cm) in diameter, carried on strong petioles. The name Petasites comes precisely from its large leaves, for the name means “like a hat” and when it rains, you can indeed pull off a leaf and wear it as a rain hat. Japanese butterbur is sometimes mistaken for “wild rhubarb”, a plant to which in fact it is in no way related. (Rhubarb is in the Knotweed family while butterbur is in the sunflower family.)

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With Japanese butterbur, you’ll soon have a waist-deep carpet of huge green leaves.

Each plant produces only 3-6 deciduous leaves, but also several underground rhizomes. These rhizomes give birth to other plants and in no time you have a vast green waist-deep carpet. It is a highly invasive plant, particularly in wetlands, but even in a normally drained flowerbed, butterbur can take over rather quickly, as it tends to smother out neighboring plants with its huge leaves.

Ideally you’d plant this weedy perennial inside some sort of barrier. One I’ve found works well is to sink a large container made of thick plastic (like a child’s pool) into the ground, leaving about 1 inch (2.5 cm) of rim exposed. (You can hide the rim with mulch after planting). Now fill in to 1 inch (2.5 cm) of the edge, plant and water well to get it started. The container will quickly give you a huge green circle of giant foliage in just a year or so, yet the plant won’t be able to spread any further, trapped by the barrier’s walls.

Note that it isn’t necessary to drill drainage holes bottom of in the container: butterbur doesn’t mind the soggy soils that occur containers with no drainage hole.

Japanese butterbur does best in moist to wet soils, but will also grow in the typical “moist but well-drained” soil of the average perennial bed. Under such circumstances, though, the leaves tend to wilt every day during hot weather, which is not a pretty sight. Plant it along the edge of a pond, though, and it will be much happier. You can even grow in a pond, with its roots slightly covered with water.

Japanese butterbur is pretty much indifferent to soil quality and adapts equally well to various light intensities. Thus it will grow in sand, humus, or clay and in sun or shade. If you grow in in full sun, keep it wet at all times. In shade, it prefers spots that enjoy spring sun, such as under deciduous trees. It is not as happy in spots that are shaded all year long.

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Hail damage to butterbur.

Note also that butterbur leaves are easily damaged or torn by strong winds or hail. This doesn’t harm hurt the plant in the long run and it will still grow back vigorously the following year, but the results are not very pretty. This is one reason why this plant is often more interesting when used in the shade of large trees that help protect it from hail and wind.

Beware too of slugs, especially in early spring as the leaves start to appear.

In addition to serving as an ornamental plant, Japanese butterbur is also a vegetable. In Japan, where it goes under the name fuki, people harvest and eat the young leaves and petioles in the spring. Note, however, that you have to prepare the leaves correctly, because otherwise they are slightly toxic.

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Japanese butterbur flowers are easy to mistake for an entirely different plant.

As with darmera, butterbur produces its flowers before its leaves appear. They seem to sprout out of nowhere in early spring on 6- to 12-inch stems (15 to 30 cm) covered with pale green bracts. Each stem bears a dense dome of pale yellow flowers. The blooming flower stalk actually looks an entirely different plant, not just a flower stem! The first time it bloomed in my garden, I thought it was a plant I’d forgotten to label! It wasn’t until the flowers and the green bracts faded and the huge summer leaves started to pop up that I put two and two together and realized that the “short yellow-flowered plants” in my garden were actually butterbur blooms!

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Variegated butterbur is most colorful early in the summer.

There is also a variegated Japanese butterbur with foliage that is marbled yellow in the spring (the color tends to fade in summer, though). It is officially called P. japonica ‘Nishiki-buki’, although it is generally sold under the incorrect name P. japonicus ‘Variegatus’.

And for lovers of truly giant leaves, there is also a giant butterbur (P. japonica giganteus) whose leaves are 3 to 4 feet (1 m to 1.2 m in diameter) on stems up to 5 feet (1.5 m) tall. Note many nurseries offer regular P. japonicus as giant butterbur. I don’t think they realize they have the wrong plant! Finding the true giant form can be difficult.

Warning: both varieties (the variegated one and the giant one) are just as invasive as the species!

Japanese butterbur is hardy to zone 4 in exposed locations, but also does perfectly well in protected sites of zone 3. It does best in cool summer areas, usually zones 8 or less.

Multiplication

All three umbrella plants described here are mainly propagated by division in spring or fall.

Other “Umbrella Plants”

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Giant gunnera (Gunnera manicata) is a knockout, but won’t tolerate cold winters.

There are other plants with rounded peltate leaves that you can grow in your temperate climate gardens, plants like Podophyllum peltatum, Diphylleia cymosa, and Syneilesis aconitifolia, but they are of a more modest size than the umbrellalike plants described here. Of course, if you live in zone 8 or warmer, you could try the most umbrellalike umbrella plant of all, the beautiful but frost-tender giant gunnera (Gunnera manicata), with leaves that can reach almost 6 feet (2 meters) in diameter.

But if you want to impress the neighbors with your own umbrella plants and you live in a climate with cool to cold winters, I suggest you start with one of the plants described above: astilboides, darmera, or butterbur. They really are quite something!20160822I

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