Bulbs

Allium is a genus of about 700 species of spring, summer and autumn flowering rhizomes and bulbs found naturally in dry and mountainous regions of the N. hemisphere. Commonly called onion these are excellent planted in groups in borders and rock gardens. There is no mistaking this genus by smell, several have a culinary use and all can be dried for arrangements. Contact with the bulbs may irritate skin and aggravate allergies. Allium likes fertile well-drained soil full sun. Many self-seed and may take up to 2 years to germinate. Fungi will attack in damp conditions rot, mildew, rust, smut and mold may become a problem.

Agapanthus is a genus of 10 species of vigorous perennials native to southern Africa. Hardy only to zone 9, northern climes use in containers. Commonly called the African blue lily, the flower is technically an inflorescence, which is an arrangement of flowers on a single stem. Keep spent flowers cut for rebloom. They like fertile, moist, well-drained soil, full sun. Overwinter in a cool, bright spot and water sparingly until growth resumes. Seeds sown take 2 - 3 years until flower, colors of agapanthus is blue or white.

Caladium is a genus of 7 species of tuberous perennials naturally found in woodland margins of tropical South America. Grown for their long-stalked leaves caladium is naturally variegated in shades of red, white, and pink. They do flower greenish white and are followed by white berries but generally in all zones in the US caladium is used as an annual. They like moist but well-drained humus rich soil, part to full shade. The use of a balanced liquid fertilizer monthly is recommended. If your intention is to lift and store in early fall is best and before temperatures drop below 55 degrees. Store dormant tubers almost dry at room temps. Prone to tuber rot, blight, bacterial and fungal leaf spot. Indoors aphids and spider mites may be a problem.

Canna is a genus of about 50 species native to tropical North and South America and Asia. There are two main groups generalis and orchiodes and they have been interbred and now thousands of complex crosses exist. Hardy only to zone 8 cannas should be lifted in the fall or moved indoors is you wish to preserve the plant. Deadhead throughout the season to promote continuous blooms.

Crocus is a genus of about 80 species of dwarf, cormous perennials found naturally on every continent except Australia. Best grown in drifts they are suitable for any location. Mice voles, squirrels like the corms and birds sometime pick off the flowers.

Fritillaria is a genus of about 100 species of bulbous perennial found in a wide range of habitats from woodland to open meadows and high screes particularly abundant throughout the Mediterranean and Asia. The leaves are worth noting simply because they aren't. The flowers are usually pendulous and often bell-shaped or tubular. Beware when buying because the bulbs are very fragile. Depending on the cultivar soil and situation requirements are specific but basically no pests worth noting.

Gladiolus is a genus of 150 species of bulbous plants with over 10,000 different cultivars. Classification is broken down into three main groups distinction is made by the flower structure and bloom time. Glads need an abundance of moisture particularly after the sixth leaf develops. Planting should be done biweekly for continuous show, two inches deep and 18 inches apart. Staking or support may be necessary. They like full sun or part shade in moderately fertile soil. Mold spider mites thrips and aphids may be a problem.

Hemerocallis commonly called daylilies is a genus of about 15 species of which there are over 30,000 cultivars. Found naturally in the forest margins, valleys and meadows thought China, Korea, and Japan. It is not a bulb but rather a rhizome that can spread and quickly overtake and bed. Flowers have five different forms each opening for just one day or evening for at least 16 hours. Generally hardy from zones 3-10 they do require dormancy. Daylilies ask only for fertile, moist, well-drained soil, full sun. When buds appear apply a balanced liquid fertilizer ever 2-3 weeks and water freely. Divide every 3-5 years to maintain the health of the plant and advice is to do it either in spring or fall. Susceptible to rust, gall, midge, aphids, mites and thrips and climate extremes can bring on stem rot but generally this is a great performer.

Hippeastrum commonly called amaryllis is a genus native to a small southwest coastal area in South Africa. It has a hollow flower stalk usually bearing 4-6 flower heads. Plant up in potting soil with the top quarter of the head exposed, they like a tight fit in a pot. The flowers have no
scent but the blooms can be a feast for the eyes. The bulb can be saved and used again next year, letting the bulb go dormant during the fall after foliage is spent. Best way to store bulbs is in shavings or as an inspired friend has done in shredded paper. These bulbs can be pricey - average cost is 6 - 8 dollars apiece.

Hyacinthoides commonly referred to as bluebell is closely related to scilla is a genus containing 4 species of vigorous bulbous perennials naturally found in the deciduous woodland and moist meadows of W. Europe and N. Africa. They like deep humus-rich, moist but well-drained soil in dappled shade. Remove flowers as they fade to prevent reseeding. No pest and diseases of note.

Hyacinthus or hyacinth is a genus of 3 species of bulbous perennials native to W. and C. Asia, and are grown for their very fragrant flowers. Depending on your zone determines the depth to plant the bulb in well-drained, moderately fertile soil in sun or part shade. Prone to gray mold and bulb rot.

Iris is either a rhizome or bulb and is a complicated genus. Iris is broken down botanically into subgenera, section and series based on cultural needs. The main division of rhizomes is bearded, crested and beardless, the bulbous irises are all beardless, they are the cute smaller irises commonly called Dutch iris. All rootstock should be planted close to, or on the surface of the soil. Found naturally throughout the N. hemisphere in a wide variety of habitats. Fertilizers high in nitrogen should be avoided. The most difficult aspect of growing iris is location they are rather particular, but full sun, well-drained soil, avoids mulches. Prone to borer, slugs, snails, weevils and aphids and if they don't get 'em blight, rot, rust and fungus may. Once a favorable spot is found for iris they will keep dividing and generally require little attention. The leaves may be cut back without concern approximately 8 weeks after blooming.

Lilies are the aristocrats of the bulbous plants. The genus contains over 80 species and is further broken down into 9 divisions based on petal arrangement. An excellent choice in woodland settings, rock gardens, bed and borders or a dramatic focus in a stand by themselves. They grow well in a variety of soils and propagation is off the bulblets that generate above the base of the old stem after flowering. Always propagate from healthy stock. Lilies are vulnerable to several types of viruses transmitted by aphids and also gray mold. Well-drained soil is a must.

Narcissus is the genus commonly called daffodil and contains about 50 species of bulbous perennials. Narcisuss are grouped in division 1-10 based on petal arrangement. Tolerant of a range of soils but like mist earth during the growing season, full sun to part shade. Cut back leaves 6 weeks after bloom has faded.

Paeonia commonly called peony is a genus of about 30 species of tuberous, clump forming, herbaceous perennials native to meadows, scrub and rocky places from Europe to East Asia and North America. There are four forms of flowers to these long-lived plants and they resent disturbance. Preferring humus-rich, moist but well-drained soil full sun to part shade. Plant rootstock just on the surface of the soil, too deep and the plant will not flower. Prone to wilt, viruses, Japanese beetles and nematodes. Pinch buds leaving two of the same size to assure size and strength of stem.

Scilla is a genus of about 90 species of bulbous perennial found in woodlands, alpine meadows and by the shore throughout Europe, Africa and Asia. Great for naturalizing under trees scilla likes moderately fertile, humus-rich well-drained soil full sun or part shade. Viruses may be the only problem.

Tulipa better known as tulips is a genus of over 100 species divided into 15 groups defined by flower characteristics, most should be used as annuals as hybrids are unreliable repeat bloomers. The cultivar determines soil preference generally plant at a depth of 8 inches in fertile well-drained soil full sun. Prone to root and bulb rot in wet or poorly drained soil, mold, slugs, snails, aphids and nematodes are a problem. Keep groupings to a single species for greatest effect.

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