How to Grow and Care for Canna Lily

Cannas (Canna × generalis) are tropical and subtropical flowering plants. Active hybridizing has resulted in an array of cannas to choose from, many with large, showy flowers and banana-like variegated leaves. Striking flowers notwithstanding, cannas are often grown for their foliage alone. Canna lilies are considered easy to grow with lots of sun, consistent watering, and balanced fertilizer applications.

Canna Lily Care

• Give canna lilies full sun. In hotter regions, some afternoon shade is welcome.
• Water generously, especially in hot climates. Make sure the soil stays consistently moist.
• Feed them in early spring and mid-summer with a well-balanced, slow-release fertilizer.
• Prune away old and faded growth as it appears.
• Use rich, evenly moist soil but make sure it is well-draining.
  

Light

Cannas do best in full sun. This means they may need more water in really hot climates, but they need heat to spur their growth. In the hottest areas, some afternoon shade helps flowers last longer.

Soil

Plant cannas in rich, moist soil, ideally with a slightly acidic to neutral soil pH.

Water

Cannas need consistent water and evenly moist soil. Water often, especially in extreme heat. Insufficient water will cause the leaves to tear or crack.

Temperature and Humidity

Blooming depends on the climate and weather. In areas with cool springs, the plants may be slow to get started. Potting them up indoors, before your average last frost date, and moving them out while they are already growing, will help them bloom earlier. As tropical plants, cannas prefer humid air but can tolerate relative dryness, especially if they are properly watered.

Fertilizer

In addition to needing lots of water, cannas are hungry plants, although they store some food in their rhizomes. Feed them in early spring and midsummer, using a balanced fertilizer. For the amount, follow the product label instructions.

Types of Canna Lilies

• 'Lucifer': This type hosts red flowers with yellow borders, has green leaves and grows up to two feet tall.
• 'The President': A variety with scarlet blossoms and green leaves, it grows three to three and one-half feet tall.
• 'Pretoria' ('Bengal Tiger'): Named for it's yellow and green striped foliage and orange flowers, this type can reach four to six feet tall
• 'Stuttgart': This canna features orange flowers, green and white variegated foliage, and grows up to three or four feet tall.
• 'Tropicanna': Perhaps the most exotic canna variety, it has dark variegated leaves with large, orange flowers or black leaves and gold flowers. It can reach six feet tall.
  

Pruning

When it comes to canna lilies, pruning is not only for aesthetic purposes but for the health of the plant. Trimming away old growth removes pathogens that can cause diseases and promotes better air circulation If your canna lily has more space, the leaves and blooms will dry faster and the risk of fungal infection is lowered. Pruning also gives your plant the signal to direct its energy towards new growth.

Propagating Canna Lily

Since most of the newer varieties are hybrids, canna lilies are generally grown from rhizomes rather than seeds. If you live in a climate with frost and would like to preserve cannas for the next season, take the following steps.

1. Cut the foliage and stem to six inches.
2. Dig up the rhizomes and let them dry in a protected, shady spot.
3. Shake off the excess soil once dried.
4. Wrap the rhizomes in newspaper, and store them in a dark, cool location until spring.
5. Check on them periodically to make sure they are not rotting or drying out.
6. Look for shoots that have at least two to three growing points or "eyes" over the course of the growing season. A single canna rhizome can become much larger, developing offshoot structures.
7. Cut away well-developed offshoots from the main rhizome to become new plants. Do this in spring, after you bring the rhizomes out of storage or dig them up for storage in the fall.
   

The size and amount of blooms of cannas are linked to the number of "eyes" on a rhizome. The more eyes, the bigger the plant, and the better its blooms. Look for rhizomes with three to five eyes, and plant them in spring with the eyes facing up four to five inches deep.

Potting and Repotting Canna Lily

Canna lily grown in a pot will need rich potting soil and good drainage. Adding pebbles at the bottom of a pot with ample drainage holes is recommended. The pot itself should be rather large, at least 12 inches in diameter, and made of any medium as long as the aforementioned drainage holes are abundant. It should also be very sturdy, as these plants can grow rather tall. The rhizomes should be planted four to five inches deep.

There may come a time when you will need to repot your canna lily. If it's appearing to outgrow its current container, check on the bottom. If roots are peaking through the drainage holes, it is time to move to a larger container. Early in spring is the best time to repot your canna. Fill the new container with rich soil, but don't pack it in - a gentle pat down will do. Water amply to help the roots settle.

Overwintering

In warmer zones, canna lilies often survive winter in the ground. If the temperatures dip below freezing for several months, it's best to bring canna lilies inside to overwinter. Do this by gently lifting the clump of rhizomes and placing the plant in a pot. Cover the pot and tuck it away in a cool, dry place, such as an unheated garage. Set the lilies back into the ground as soon as the soil is soft enough to work.

Common Pests & Plant Diseases

Canna leaves are covered with a waxy substance that repels water and protects against fungus. They may be bothered by rust or bacterial blight, especially in poorly drained soils. Pest problems can include leaf rollers and caterpillars, while slugs and snails may munch on the leaves.

How to Get Canna Lily to Bloom

Canna lilies are treasured for their flowers and foliage. Their large, paddle-like leaves come in greens, blue-greens, and bronze and can be variegated and striped. Their blooms are equally showstoppers.

Bloom Months

Canna lilies typically bloom from June to October. In planting zones 8 and up, cannas will repeat-bloom throughout summer, and throughout the year in zones 9 and above.

How Long does Canna Lily Bloom?

A single canna lily bloom can last for up to a week before fading.

What do Canna Lily Flowers Look and Smell Like

Canna flowers are somewhat tubular and lily-like, coming in shades and combinations of yellow, orange, red, and pink, and are borne on tall stalks poking out of the foliage. Canna lilies are not fragrant.

How to Encourage More Blooms

To keep canna lily blooming all season, make sure the plant has full sun, as well as a spring feeding of 5-10-5 fertilizer. For the amount, follow the product label instructions. Give them plenty of water weekly and deadhead the blooms as they begin to fade, thus encouraging more growth. Check to be sure the rhizomes are no more than two to three inches deep in the soil, as planting them too deep will stunt the plant's growth.

Canna lilies that are too crowded will fight for nutrients, and that means fewer blooms. To remedy this situation, divide the lilies every two to three years.

Caring for Canna Lily After It Blooms

Once your canna lily's blooms begin to fade for good, you should snip them all off so the plant doesn't waste energy on spent flowers. The space above the second flowering node is where you want to cut. As you head into winter, wait for the first frost. The foliage will turn black. This is your sign to cut the plant all the way back to about 6 inches above ground level and add a layer of mulch.

Deadheading Canna Lily Flowers

Always deadhead fading flowers during the blooming season. This will encourage more blooms and extend the flowering period.

Common Problems With Canna Lily

Though canna lily often grows beautifully for years, the plant might encounter some problems. Here are the most common.

Leaves Stuck Together or Covered in Black Droppings

This is the work of the leaf roller, a tiny pest that can pull together leaves with silky strands to hide and feed. A good insecticide will do the trick.

Holes in Leaves

When you see holes in leaves, that's the telltale sign of snails or slugs. Remove these by hand or use a horticultural oil to keep them away.

Curling Leaves

Aphids leave a sticky sap behind that can curl up the leaves of your plant, leaving it quite unsightly. Blast them away with a water hose or use insecticide for serious infestations.

Fuzzy Mold

A plant covered in fuzzy mold is infected with Botrytis blight. This fungus can be treated with a fungicide. If the infection is severe, consider removing the plant.