Angel Wing Begonia

Begonia involucrata at Monte Verde

The simple pink or sometimes red or white flowers of angel wing begonia are not as flashy as those of other begonias, and are not abundant enough to provide much color. During warm weather, they are merely a minor bonus to the striking foliage. As the name implies, the big and angularly lobed leaves are shaped like wings of angels. Upper surfaces are glossy and dark green with irregular silvery spots. Undersides are even glossier and reddish bronze. With support, the lanky cane stems can get more than twelve feet tall. However, because older tall canes produce runty foliage, they are often pruned out to promote more vigorous and lushly foliated young canes.

Because they are sensitive to frost, and also because they are ideal houseplants, angel wing begonias are typically grown in containers. They like rather regular but not excessive watering, and rich potting soil. Abundant sunlight enhances foliar color; but harsh exposure roasts foliage. Partial shade is not a problem.

Philodendron selloum

Philodendron selloum is unfamiliar with autumn.

There are all sorts of philodendrons with all sorts of fancy names. Yet, the biggest and boldest lacks a common name (at least one that is actually ‘common’), and is most popularly known by a Latin name that is not even correct. The proper name for Philodendron selloum is really Philodendron bipinnatifidum. It is a big awkward plant with big and deeply lobed leaves on long petioles (leaf stalks), and weirdly thick aerial roots. Well exposed plants can stand on wobbly trunks. Partly shaded plants can creep along the ground, and prefer to grab onto and climb tree trunks, fences or anything that they can get a hold of. The aerial roots are harmless to trees, and generally too slow to catch a healthy cat, but will take paint off of walls. All parts of Philodendron selloum are toxic.

Japanese Aralia

The bold foliage of Japanese aralia is quite striking, whether kept low and dense, or suspended on taller lanky stems.

It may not grow too rapidly, but Japanese aralia eventually gets nearly eight feet high and wide, and commands a bold presence. The deeply and symmetrically lobed leaves can get as broad as a foot and a half, on long petioles (stalks). The foliage of ‘Vairegata’ emerges with a yellow border that turns pale white. ‘Moseri’ stays quite compact.

Plants grown for their foliage can be maintained by cutting the oldest stems to the ground as they begin to deteriorate, so that newer stems can replace them. Alternatively, lower growth can be pruned away as it develops to elevate the canopy and expose interior stems. However, individual stems do not last indefinitely, and will eventually need to be replaced by any convenient watersprouts.

Coleus

No flowers needed with this foliage!

Out in the garden, coleus, Plectranthus scutellarioides, prefers partial shade where the foliage is less likely to get roasted during arid and warm summer weather. It is grown as a warm season annual instead of as a perennial, because it gets so tired through winter, and can be killed by even a very mild frost. Its sensitivity to exposure in the garden is probably why it is more familiar as a houseplant.

The flashy and sometimes deeply lobed foliage is variegated with any combination of green, chartreuse, yellow, orange, red, burgundy, pink, white, brown and almost black. Flower spikes should be snipped as they develop to keep foliage dense. The tiny purple flowers are not much to brag about anyway. Large plants can get to two feet tall and broad. Cuttings root easily in rich and regularly moist potting soil or just plain water. Seeds need sunlight to germinate, so should only be pressed onto the surface of damp potting soil without getting covered, and misted daily.

Houseplants Bring The Outdoors In

Many houseplants will not live outside.

There is someplace in the world for the brethren of each and every houseplant to grow wild. All houseplants do not originate from the same regions, and many were bred in cultivation, but all originate from somewhere. They are houseplants only because they are plants that can live in a house.

Most houseplants are from tropical regions, and many are understory plants that grow in the partial shade of taller trees. They are naturally tolerant of the mild temperatures and partial shade within the home. Not many deciduous plants will be happy without a winter chill.

Confinement is also a concern, since houseplants need to be potted, and stay below ceilings. Plants that need to disperse their roots will not work. Neither will plants that can not be pruned down as they grow. Some palms that work well in malls have leaves that get longer than the distance between the floor and ceiling in the home!

Most houseplants are grown for foliage instead of flowers, not only because a lack of seasons inhibits bloom, but also because their foliage is naturally so appealing. African violets are one of the more notable exceptions. Amaryllis is all flower with almost no foliage, but typically gets discarded when done blooming.

Coleus and caladiums have such colorful foliage that there is no need for flowers. Bloom actually compromises their foliar quality anyway, which is why flower spikes get snipped from coleus. Mauna loa lily is grown for excellent rich green foliage, but sometimes adds clear white blooms as a bonus.

All sorts of ferns are very good houseplants. However, a few, including the popular Australian tree fern, produce coarse fuzz that can be irritating to the skin. A few others, like sword fern, produce messy spores that can permanently stain fabric and carpet. Just because they can live in the home does not mean that they should.

The various ficus are excellent houseplants because they can grow quite large, but can also be pruned to fit into their particular situations. The popular weeping fig (Ficus benjamina) has an abundance of small glossy leaves. Rubber tree and fiddle leaf fig have big thick leaves. Creeping fig is even more distinct from the others, as a wiry vine that is popularly grown in hanging pots.

Rabbit Foot Fern

 

Rabbit foot fern has lacy leaves.

Rabbit foot fern, Davallia fejeensis, is one of those few plants that actually seems to be happier in pots, particularly unglazed terracotta pots that stay damp where its oddly fuzzy rhizomes creep over the edges. Besides, pots have the advantage of portability, so that appealing plants can be brought into the home as houseplants, even if only for a few months at a time. Rabbit foot ferns that lose leaves because the air in the home is too dry should recover if moved to a shady and humid spot out in the garden for a while.

The fuzzy rhizomes are as appealing as the foliage, and can creep a foot or even more if they wrap around a pot. They rot if buried, so should be spread out over the surface of the potting soil when small plants get put into larger pots. The very lacy foliage can get a foot deep in damp and partly shady spots. Foliage is shorter and more dense with more sunlight.

Elephant Ears

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The origin of taro is vague.

Taro was grown as a vegetable in ancient Egypt. It was grown in India before that. A few hundred varieties were cultivated in precolonial Hawaii. Taro was likely native to southeast Asia, but has been in cultivation for so long that it is difficult to know where it originated from. In modern American gardens, it is known as elephant ears, Calocasia esculenta, and grown for its striking foliage.

The big and broad leaves are held as high as six feet on long petioles (leaf stalks), and flare out as broadly as three feet, although many varieties get half as tall and broad. Some varieties have weirdly dark foliage. Others have green leaves with colorful veins. A few are simply jade green. Any of the deciduous foliage that lingers into winter should be cut back before spring.

Since they are naturally bog plants, elephant ears likes very rich potting soil and plenty of water. Muddy clay soil that will not float away works fine for pots submerged in ponds. (Ick!) Partial shade is important. Leaves can get roasted if too exposed. To propagate, corms can be divided while dormant in winter. All parts of elephant ears are toxic until cooked.

Boston Fern

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This fern is nowhere near Boston.

It is not actually from Boston. The first Boston fern, Nephrolepis exaltata ‘Bostoniensis’ was merely discovered in Boston, as a mutant in a shipment of otherwise normal ferns. Unlike the more upright parent plants, Boston fern has softly arching fronds that can hang vertically at the ends.

The fronds are typically about a foot and a half long, and can be a few feet long in humid and partly shady environments. Each frond is comprised of many pinnae that are neatly arranged on both sides of a wiry rachis (leaf stalk). Each leaflet is an inch or two long or longer. Delicate aerial roots sometimes dangle below the foliage.

Through the 1970’s, Boston fern was one of the most popular houseplants. Yet, it really prefers more humidity than it gets inside. It is actually happier on porches or in atriums where it is sheltered from frost and harsh sun exposure. It prefers partial shade outside, but likes abundant ambient sunlight as a houseplant.

Ferns Are Made For Shade

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Ferns are famous for distinctive foliage.

Without color or fragrance of flowers, ferns provide some of the most distinctive foliage in the garden. They do not turn color in autumn. Only a few tree ferns develop sculptural branch structure. Yet, they do their job well, and many are happy to do so in spots that are a bit too shady for other plants.

Almost all ferns are low perennials that produce foliage that arches outward from the center. Some can get quite broad. A few tree ferns grow upward on trunks (although the trunks are merely tough roots that grow through decomposing stems). Australian tree ferns can get quite tall and broad where sheltered from wind.

The staghorn fern is a weird epiphyte that naturally clings to tree trunks or rock outcroppings where it collects organic debris that falls from trees above. In home gardens, it is popularly grown on wooden plaques or as a hanging plant. Hanging plants do not necessarily need pots, or sometimes engulf their pots as they grow.

Leaves of ferns are known as ‘fronds’, and with few exceptions, are intricately lobed or divided into smaller leaflets known as ‘pinnae’, which are arranged on opposite sides of leafstalks known as ‘rachi’ (or singularly as ‘rachis’). The staghorn fern has unusually branched but otherwise unlobed fronds. The bird’s next fern has has distinctively simple fronds without any lobes or pinnae.

Most of the popular ferns are naturally understory plants that grow below larger plants. Even most tree ferns grow amongst larger trees. This is why so many ferns tolerate shade so well. In fact, many prefer partial shade, and will actually fade or scorch if too exposed. However, it is also why so many ferns prefer rich soil with an abundance of organic matter.

Maidenhair, rabbit’s foot, bird’s nest, holly, Boston and a few other ferns are popular as houseplants. Because home interiors are a somewhat arid for them (lacking humidity), some ferns like to be misted daily. Ferns respond well to regular but light application of fertilizer. Too much fertilizer can roast foliage.

Because ferns are not expected to bloom, nitrogen (which can inhibit bloom for some plants) is not a problem. Ferns that are out in the garden can therefore get fish emulsion or a bit of the same sort of nitrogen fertilizers that keep lawns green.

Herbaceous Trees

P91005KPalms are like ‘Red Delicious’ apples. It seems that most people dislike them; but they also seem to be very popular. Seriously, if only a few people like ‘Red Delicious’ apples, why are they so common in supermarkets? If most of us dislike palms, why are they so common in the San Jose Skyline?

I suspect that palms really are as unpopular as they seem to be, but that they are also very conspicuous within their situations. Not only are they focal points of the landscapes in which they live, but most types eventually stand as tall as the tallest trees in the neighborhood, and some get significantly taller. They are innately the most prominent trees within their neighborhoods.

Palm are not like other trees though. Arborists may classify them as ‘herbaceous trees’. They are foliar plants while young, producing increasingly large leaves from terrestrial rosettes. They only ‘launch’ and start to develop their trunks after the formerly terrestrial rosettes have grown wide enough to do so.

Not only are their trunks no wider than their associated foliar rosettes, but they get no wider as they grow taller. The base of a trunk of a palm is as wide when the tree is only a few feet tall as it will be when the tree grows to forty feet tall. Mexican fan palms are only wider at their bases because they start out like that.

Palms with slender trunks can launch much sooner than those with wider trunks. It does not take long for their rosettes to get as wide as their trunks. Canary Island date palms have rather plump trunks, so may need to mature for many years before they launch.

Yuccas and dracaenas are not really palms. Their trunks expand and develop branches as they grow and mature.