These easy-to-grow plants are often referred to as canna lilies.
Plant the rhizomes after the last frost.
Once the weather warms up and sprouts emerge, they grow quickly and start blooming in about three months.
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The name comes from the Greek word kanna, meaning a reed or reed-like plant.
Heres everything you better know about growing and caring for cannas in the South.
Nikki Snowis an owner ofHorn Canna Farmin Carnegie, Oklahoma.
Hummingbirds will visit to feed on the nectar.
you might buy cannas in containers or as bare rhizomes.
For rhizomes, do not plant until soil temperatures have reached 60oF or warmer.
When planting, set the rhizome on its side horizontally and cover with 1 to 2 inches of soil.
Do not plant too deep because they love the heat from the surface of the soil, says Snow.
Space canna rhizomes about 12 to 18 inches apart in the garden.
They can tolerate heat, some drought, and moist soils.
In good conditions, they will spread each year in the garden.
They will tolerate partial sun but produce fewer flowers.
If you plant in part sun, double-check your cannas receive four hours or more of sunlight.
Afternoon shade can help prevent foliage from burning in hot, dry climates like the desert Southwest.
Soil
Cannas tolerate neutral to slightly acidic pH levels.
They appreciate rich, moist, well-draining soils.
Clay and sandy soils can beamended with compostto improve the soil.
Water
Water cannas at planting time, then throughout the summer if its dry.
Cannas do best with a deep soaking once a week, says Snow.
Aim for 1 or 2 inches of water each time.
During very hot, dry weather, you might increase watering to two or three times a week.
Cannas are moderately drought-tolerant once established and won’t suffer if you miss a watering in many gardens.
They’ve even been planted along highways in some states.
However, cannas require more water in an arid climate or in a hot climate likesouthern Florida.
Add a layer of mulch around your cannas to help conserve moisture.
The plants wake from dormancy once the soil warms and grow vigorously during hot weather.
High-nitrogen fertilizers increase the height of the plants but may result in scraggly blooms.
Apply two to three times over the course of the growing season.
Fertilized cannas sometimes attract more pests.
If you find them unsightly, clip off the stems just below the blooms.
More flowers are developing further down, and you don’t want to remove them.
Once all flowers on a stem have bloomed, you could cut it down to the base.
The entire plant begins to look scraggly once the first frost hits.
Plants can suffer some damage from cold weather, even in frost-free areas.
Propagating Cannas
Cannas have large rhizomes that enthusiastically grow and spread in warm climates.
The tall plants can shade and overpower more delicate plants in the garden.
Removal provides plenty of opportunities for dividing and sharing plants.
it’s possible for you to also divide overcrowded clumps every two to three years if flowering becomes lackluster.
Division is best done in spring when the soil is warm enough to replant the rhizomes.
Or, plant one rhizome in a 15-inch pot.
Use a high-quality potting mix and plant your rhizome horizontally 1 to 2 inches deep, then water well.
Potted cannas need frequent, often daily, watering in summer.
Place a saucer under the plant to help retain moisture.
Use a slow-release granular fertilizer that is formulated for flowers according to package directions.
The large rhizomes can outgrow pots quickly.
If your cannas become root-bound, lift and divide the rhizomes and replant.
This allows some natural moisture to be retained so that the rhizome will not dry outover the winter.
In Zone 7, cut the foliage back almost to the ground after the first frost.
Cover the crown with a thick layer of insulation, such as straw or leaves.
Gardeners in Zone 8 and warmer don’t need to take extra steps to protect cannas in winter.
The ideal storage temperature is around 50, but most importantly, it must remain above freezing.
But they may take a nibble if you have a large population of deer in your area.
The canna leaf roller causes the ugliest damage to foliage.
Moths lay eggs in the developing stems, then damage is revealed as the tattered leaves unroll.
If you see leaves held together with webs, unroll them toremove caterpillars.
Removing foliage each winter helps reduce the population.
Slugs and snails may chew holes in the leaves but aren’t usually a serious problem.
Japanese beetles enjoy feasting on the flowers.
you might pick them off and dunk them in a can of soapy water.
Canna viruses can be a problem, causing spotted or streaked leaves, stunted growth, and distorted blooms.
Severely affected cannas should be discarded.
Finally, rust is a fungal problem first detected when orange or yellow pustules appear on the plant.
High humidity and inadequate sunlight contribute to the problem.
Leaves may eventually turn yellow, and large rust-colored patches can form.
Remove the affected leaves and dispose of them, then spray the plant with a fungicide labeled for rust.
The problem can be difficult to control once it appears.
Cannas take about three months to develop flowers after planting.
Consider starting your plants indoors a few weeks before you plant them to extend the growing season.
Cannas bloom best in full sun.
Drought or overcrowding can reduce blooming.
Provide consistent moisture and divide if needed.
Over-fertilizing can also prevent blooming.
Use a slow-release, organic fertilizer formulated for flowers.
Weather conditions can also affect plants and cause the problems below.
Consider moving your plants if they are in an exposed, windy area of the garden.
Tattered leaves can also be a sign of under watering, as discussed below.
Brown Leaves
Plants that develop brown, crispy margins on the leaves usually need more moisture.
The leaves may begin to separate and become tattered.
Check the soil and water more frequently as needed.
Yes, cannas can spread through underground stems and can become very large and/or crowded.
To prevent overcrowding, you’re able to divide and replant every 3-5 years.
Canna rhizomes don’t require soaking before sprouting.
Water deeply at the time of planting and then wait until growth begins before watering again.
