Growing Canna Lily

Latest Update 2nd July 2015.

Canna Lily 
  • Best grown in groups, they come in a large range of colours.  I have the bright red variaty as shown in the photo and a miniature bright yellow one.
  • When a flower is finished, I cut down the whole stem of the canna lily and use it coursely chopped in my compost heap, and sometimes as worm food.  This promotes new growth and eventually, more flowers.  Canna lily foliage is said to be rich in nitrogen and trace elements.
  • Binomial Name:                                       Canna Verdi.
  • Family:                                                   Cannaceae.
  • Garden bed type:                                     Drip line irrigated. 
  • Plant Spacings (centres):                          300mm. 
  • Climate:                                                  Warm Temperate.
  • Geography:                                             Southern Hemisphere. 
Growing Conditions:
  • They require full sun.
  • They die back to the ground in winter and although frost tender, they will over-winter well under a thick cover of straw mulch (warm temperate climate).
  • Minimise soil disturbances to maintain a natural soil structure. 
  • Although sandy soil is recommended, I have been growing mine for many years in well structured heavy clay soil improved with a regular supply of compost and aged animal manures. 
Propagating new plants.
  • To propagate canna lilies, use a garden fork to dig up a whole plant and divide the tubers by hand.
  • Select the best tubers (those with the most attached root and with a healthy new shoot) and plant them in a prepared bed.
Preparing a new bed.
  • Clear a space for your new plants in September and dispose of any organic waste in the compost.
  • When replacing an old canna lily, choose a spot which hasn't grown them for at least 3 years.
  • Apply a 60mm thick top dressing of home made compost and cover with fresh straw mulch.
  • Leave for 4 weeks to boost worm and microbial activity.
Growing Instructions
  • Move some of the mulch to one side and dig a hole twice as big as the new plant's tuber.  Place the plant in the hole and back fill with soil leaving the tip of the new shoot exposed.  Water it in well with dilute seaweed extract.
  • Water the plants every few days until they are established, and then allow the drip irrigation to take over.   Move the mulch back over the plant to protect it against unexpected frost.
  • Cut the stems of dead flowers close to the ground to make way for new growth.
  • Prune them all down to the ground in winter and apply a generous layer of homemade compost covered with straw mulch on top of the surrounding soil.
  • Spray the plant's foliage with aerated compost tea every month at the same time as the edible plants are sprayed.
Organic Pest Control. 
  • My Canna Lily have been pest and disease free for many years, but can be effected by the following:-
  • Caterpillars. 
    • I use aerated compost tea as a foliar spray on all my ornamental plants.  It strengthens foliage and provides a biological barrier to plant pathogens.
    • As a last resort use bacillus thuringiensis (Dipel in Australia) as a foliar spray, it becomes a potent (organically certified) killer of caterpillars.  When ingested by leaf eating caterpillars it releasing toxins into their gut, stops them feeding and they die within a few days.
  • General:
    • Regular foliar sprays of aerated compost tea boosts the natural defences of plants by colonising the leaf surfaces with beneficial microbes.  These microbes defend the plant against airborne pests and diseases.
    • Similarly, proper soil preparation including annual applications of home made compost boosts the community of beneficial microbes, which defend the plant's roots against pathogens.