Garden Mastery Tips
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January/February 2003 |
Big-Leaved Plants
Is your garden looking a little mundane and like every other garden on the block? Want to pack some punch into it? Try tucking some big-leaved plants into the landscape, sit back and let them grow and grow and grow and grow and grow.
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| Gunnera |
One of the largest big-leaved plants is Gunnera, commonly known as the Giant or Prickly Rhubarb. Giant really describes this towering plant. It can easily reach a height of 8 feet and gets as wide or wider than that. The leaves are lobed, toothed, and somewhat frilled with spine-like hairs on the leafstalks. To keep it happy in your garden, plant it in deeply cultivated, moist soil that is rich in nutrients and organic material. It will do better in a sheltered location and thrive if you locate it near water or a bog. Gunnera are heavy feeders. For spectacular foliage, you should feed your gunnera three times a year, beginning when the new growth starts. As summer progresses and the humidity drops, water it by overhead sprinkling. Tiny red fruits follow flower clusters, which form close to the roots and resemble corncobs. When winter comes, mulch the crown of the plant heavily. The most common cultivars are G. manicata and G. chilensis also known as G. tinctoria. The World Plant Shop has additional photos and a great write up on Gunnera grown by a gentleman in Eugene Oregon.
If you don’t have room for a Gunnera try growing some Rheum. Your grandmother probably grew it in her garden and called it rhubarb. Rhubarb leaves are large, crinkled and heart shaped with thick, typically red-tinted stalks. The tart flavored stalks can be used as fruit in sauces and pies. The leaves are poisonous, but can be left on the ground around the plant to provide weed control. Late winter or early spring is the best time to find someone with rhubarb they will share. Get a division and set it with the top in deep, moist, humus-rich soil at the soil line. They can be grown in sun or partial shade. If you are going to eat your rhubarb, wait until the third season. At that time, you can pull off leafstalks for 4 to 5 weeks in the spring. Grasp them near the base; pull sideways and outward If you cut them with a knife, a stub will be left that can decay. In mild winters, the plant will not completely die back. Check out The Rhubarb Compendium to find out obscure rhubarb facts and over 300 recipes to try.
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| Elephant's Ear |
Another large leaved plant is Alocasia or Elephant’s Ear. The leaves are heart-shaped to arrowhead-shaped and range from 8 inches to 36 inches long depending on the species. The leaves can be long-stemmed with distinctive red or purple markings. Most species are totally intolerant of frost. Mulch heavily over the crown or lift the tubers to overwinter.
Acanthus mollis or Bear’s Breeches is a shade tolerant plant with deeply lobed, glossy deep green soft leaves. The plant is semi-hardy and can grow to 3 feet tall, with a slightly less spread than height. In dry hot weather, the leaves are prone to drooping. The crinkled flowers are white with purple tinted stems that can reach 6 feet in height. It likes partial shade with average to rich soil. It can tolerate dry conditions and will spread by underground rhizomes once it has been established.
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| Bergenia |
Bell shaped flowers held aloft on short-branched red or purple stems signals the arrival of spring in the Pacific Northwest. The Bergenia is blooming. This clump forming plant has distinctive rosettes of glossy paddle shaped leaves, many of which color well in the fall and winter months. Divide the clumps in 3 or 4 years when the plant looks crowded and flowering begins to decline. Plant them in humus-rich moist but well-drained soil in full sun or partial shade. They dislike extremes of heat and drought, but will tolerate exposed sites and poor soil. Conversely enough, dry conditions promote vivid leaf color in the fall.
The rage all last summer in the garden centers was Canna ‘Tropicana’. The foliage alone would make this plant a standout in your garden. It has wide purplish leaves that are striped in red and yellow. It can grow to a height of 7 feet and has a bright bold orange flower. If this is a little too splashy for your garden, there is a canna color for everyone. They come in shades of red, orange, yellow, apricot, cream and pink. Leaf colors can be reddish-purple, bronze or green. Plant tubers in rich soil 5 inches deep and 12 to 18 inches apart after all danger of frost is past. These plants love the sun and thrive in hot dry weather. Water their roots and feed them heavily. They will reward you with quick growing heavy foliage and large flowers. Cut the flowers when they have finished blooming. After the first frost, let the plant dry for a few days and then cut it off. Protect the tubers with a thick layer of mulch during the winter.
Ricinus communis or Castor bean is a bold striking annual plant that can grow 6 to 15 feet and half as wide in a single season. It has glossy palmate lobed leaves with spikes of small cup shaped flowers followed by attractive prickly capsules that contain seeds. The seeds can be very poisonous to humans and some domestic animals. In addition, the foliage can aggravate skin allergies. Soak the seeds for 24 hours before sowing ½ to 1 inch deep in fertile, humus-rich, well-drained soil in full sun after all danger of frost is past. Stake in exposed sites. Water them freely and apply a balanced liquid fertilizer monthly. To prevent seed formation, pinch off the seed capsules while they are small.
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| Globe Artichoke |
Cynara scolymus or globe artichoke is related to the thistle. It has delicate gray-green leaves and is easy to grow in most soils and positions though it prefers full sun and shelter from strong winds. The richer the soil, the better the production. In early spring, plant divisions rather than seeds. In the fall remove yellowing leaves and stems. Cut the plump flower buds from the plants in spring and summer before the flowers begin to open and enjoy the artichoke fruit. Or let them open into a six-inch bluish thistle-like flower. The Gutsy Gourmet website will tell you everything you wanted to know about the history of artichokes and give you lots of recipes to try.
Musa basjoo “hardy banana” is a fast-growing plant to 10 feet with soft thick stems. It spreads by suckers and underground roots to form clumps that are as wide or wider than the plant is tall. The suckers can be dug and shared, or located in other spots of your garden. The long broad leaves are easily tattered by strong winds so plant it in a sheltered location. The hardy banana does best in full sun with a fertile, well-drained, organic-rich soil. It is a heavy feeder and requires lots of fertilizer to show off to its best advantage. If the plant is hit by frost, it will re-grow from the roots. It can also be grown in tubs and wintered indoors. Keep it well mulched.
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| Ligularia |
Lastly, let’s talk about Ligularia. The foliage resembles rhubarb with large heart-shaped leaves. In the summer, dark yellow or orange flowers are borne on tall spikes. The plant needs full sun and moist but well-drained soil.
All of the above mentioned plants would add a touch of the exotic to your garden. Maybe one of them will find their way into your yard. Most of them are readily available at your local nursery in the spring.
References
Brenzel, Kathleen Norris. Western Garden Book. Menlo Park, California: Sunset Publishing Corporation, 2001.
Brickell, Christopher, and Judith D. Zuk. The American Horticultural Society A-Z Encyclopedia of Garden Plants. New York, NY: DK Publishing. 1997.
Turner Jr., R.J., and Ernie Wasson. Botanica. Australia: Random House, 1997.