NEW and interesting plant varieties begin to captivate our attention at this time of year with the end of a not-so-long winter almost in sight. What is the plant that we will all want to have in our gardens? Like a newlyreleased song that rises to the top of the music charts, a new plant introduction has a way of seizing our imaginations.
The calla lily has been under our noses for a very long time. Grown since the days of ancient Rome and said to have been used to mark the passage of the winter solstice, the calla lily is synonymous with elegance. Beyond their soaring popularity as a cut flower, callas are proving their value for cold climate gardeners as an addition to the semi-shade landscape or as a pot or patio plant. With stronger stems, more colours to choose from, improved disease resistance and larger flowers over a longer period of time, expect to be tempted by this year’s new varieties.
On a visit to Winnipeg last fall, Adrian Espinoza, a calla grower from Salinas, Calif., painted a picture of his vast fields of colourful calla lilies in his presentation to an audience of local greenhouse owners. Owner of Coastal Callas, Espinoza grows his crop on sandy loam soil a mere four kilometres from the Pacific Ocean.
Mostly started from seed, his crop takes about two years to develop. In the first year, says Espinoza, there is mainly vegetative growth. The prevailing Mediterranean-type climate with its mild winter allows for the callas to have an extended growing season, which produces bulbs with multiple eyes. The advantage to multiple eyes is that the bulbs result in plants with more leaves, a larger number of flowers and a longer lasting performance.
The botanical name for calla lily is Zantedeschia. Varieties are distinguished by types that have plain, narrow leaves (Zantedeschii rehmanii), maculated (spotted) arrowshaped leaves (Zantedeschii elliotiana) or spotted, narrow leaves (Zantedeschii albomaculata). Elliottiana hybrids are mostly yellow and white calla lilies that have stronger stems, but not as many flowers, whereas the plain-leaf Rehmannii hybrids are a bit shorter with a greater abundance of flowers.
Originating from rhizomes, the canna lily’s funnel-shaped flower consists of a spathe, which is a large modified leaf that enfolds a prominent finger-like spadix in its centre. The spathe, sometimes with a waxy or silky texture, is borne atop a leafless stalk.
It’s the wide range of colourful blooms that really distinguishes calla lily varieties today. From hot pink, flaming orange or soft lavender, to plum red, sizzling cherry and nearly black, there’s a calla lily for every container design. Still favour classic white? Creamy white varieties are available too. Coastal Blush, for example, is a white plain leaf calla that becomes a light pink blush with age.
Erna Wiebe, co-owner of Oakridge Garden Centre, Steinbach, uses callas mostly in patio pots. "They add height but also a wonderful, delicate beauty to shade pots," she says. Wiebe likes to combine callas with begonias, ferns such as Boston or Kimberley Queen, impatiens and trailing ivy. "The whole pot takes on a tropical, but also classic, serene beauty," notes Wiebe, who adds that when the flower is finished, the foliage continues to provide the container design with a stately impact. A Downton Abbey effect, perhaps?
If anything, the calla has a sensuous beauty. Wiebe is bringing in a number of potted varieties from Coastal Callas including Fire, Glow, Gold, Flame, Lavender, Sensation and Hot Cherry. Fire has unique plum red colour with a fiery red outer flower lip and a maculated leaf. Glow, a more compact variety, has a plainer leaf, hot pink flowers, and is said to be highly productive. Espinoza says that Hot Cherry, with its waxy cherry red blooms and spotted leaves, is also highly productive and considers it to be one of the best varieties on the market today.
About 15 per cent of Espinoza’s crop is grown from tissue culture (the cultivation of plant cells in a specially formulated nutrient media). Varieties such as Hot Cherry and Hot Chocolate are grown from tissue culture. True to type, these unique varieties don’t develop seed and cost more than the seed grown varieties.
Sue McLeod, co-owner of Glenlea Greenhouses, plans to carry several varieties of potted callas including compact pink and purple varieties. Lipstick, a medium-tall calla has hot-pink flowers and plain leaves. On the taller side, Coastal 24K sports a yellow ruffled flower with a deep, dark eye and an arrow-shaped spotted leaf.
Black flowered calla lilies make a particularly bold statement. This year, McLeod is trying Hot Chocolate, a Coastal variety with a waxy leaf and flower as well as Palermo Black from Paridon Horticultural. A 2016 Plant of Merit, Palermo Black’s mysterious black funnel is offset by its medium-green spotted foliage. Or try starting your callas from bulbs. Tuxedo Time, for example, available this spring at Jensen’s Nursery, is a unique mix of callas in black and white. For stunning orange colour, Tammy Jensen, coowner, recommends Captain Safari. T& T Seeds will have Palermo in bulb form as well as Coastal Fire, Hot Cherry and Coastal Gold.
If you do decide to start your own bulbs indoors this spring, Espinoza emphasizes the importance of using welldrained potting soil with high air porosity to allow even moisture. Planting depth is important, too. Plant tubers 2.5 centimetres to 3.8 cm below soil surface. Sprouts or eyes should face up and the rounded side of the tuber should face downwards. Since roots from the tubers develop from the top, planting them too shallow will stress the plant and result in poor performance.
To kill your developing plant, simply add too much water.
Water management is critical, not only in the early growing stages, but also as the plant matures, says Espinoza. Too much water can lead to disease, while too little water can adversely affect flower production.
Once all risk of frost has passed, introduce your callas to the outdoors gradually so as to condition them to the brighter light. Although sun tolerant, callas perform best in a location with morning sun and afternoon shade. To ensure good root, tuber and flower stem growth, feed your calla at planting time with an all-purpose fertilizer such as 20-10-20. Espinoza says that callas benefit from a small amount of calcium which helps to prevent disease. A locally produced fertilizer such as Evolve Organic Bloom Enhancer 0-4-0 has 1.4 per cent calcium. Just mix with the recommended amount of water. It will also add phosphorus for bloom production.
Espinoza says that properly spacing your calla lilies to allow for light and air circulation will improve plant habit and flower colour. With proper care and adequate fertilizing, calla lilies can last up to three months in your garden. The spotted leaf types, even without blooms, have extended value as a foliage plant. Once a bloom is spent, just follow the flower stem to the base, pull and snap. This can allow for new blooms to come up.
If you like, the bulbs can be lifted each fall, over a period of up to six years, and easily stored for winter. For bulbs that are grown in patio pots, Espinoza says to simply cut off the tops and store the pot indoors in a cool, dry, dark environment that is well-ventilated. To store bulbs indoors that have been planted out in the garden, cut the tops, unearth the bulb, and remove the soil. Do not cut the roots, says Espinoza, and if possible, store the bulbs in a tray or container with perforated openings on all sides that will allow for good air circulation (such as the plastic milk trays from grocery stores).
McLeod recommends occasional monitoring for sprouting.
"If the sprouts start to elongate, plant in well-drained soil and place in a sunny window until it is time to return outdoors," she says.