How to Grow Canna Lilies From Seed
By Ashleigh Smith
Canna Lilies are one of the most beautiful flowers! They have bright, unique blooms that develop in the early to mid-summer. Once you get your seeds going, your plants will continue to produce tubers allowing your canna collection to grow each year. The canna lily has become very popular throughout the U.S. because of its tropical look and ability to thrive in temperate zones. Its large, thick leaves will have you feeling like you are in a coastal beach town. It is best to remove the tuberous rhizome roots in the fall and replant each spring as you would other bulbs.
Tips and Tricks for Germinating Canna Lily Seeds
While these flowers are propagated via rhizomes, their seeds are just as easy to start for a fresh plant of your own. Because their seeds have a hard coat, it is best to scarify and soak them to reduce the germination time. Germination usually takes 2 weeks. It is best to start your seeds 2 months before you plan to transplant outside. Follow our recommendations below to get your seeds started.
Step 1 - Scarification
Scratching or nicking a hard seed coat to enable a root to emerge with greater ease. Heat may also be used to soften the seed coat making it easier for the emerging root to push out from the seed.
- Scratch - Use sandpaper to scrape off the seed coat or run the seed along the junior hacksaw blade. Be careful not to go too deep, just until the lighter-colored inside is visible. While you may have success without this step, it is recommended.
Step 2 - Soaking
To help soften the seed coat and trigger germination to occur, soak your seeds. A minimum of 24 hours is recommended. However, you may continue to soak the seeds in shallow water if you are regularly checking on the germination status of your seeds. After the initial soak time, the seeds should not remain completely submerged. Sprout in lukewarm water, changing it out every day. With this method, germination is common in 2-5 days.
Step 3 - Planting
Cannas can get quite large quickly. It is best to start seeds in larger pots rather than a tray insert. Plant your seeds 0.25 inches deep. For the quickest results, keep the soil around 70-75 F for germination. You will see one leaf develop first from your new sprout.
Step 4 - Harden Off
Just as you would do with any plant, it is important to harden off the seedling before transplanting. Over the course of 1-2 weeks, set your seedling outside for increasing amounts of time until it can handle staying out overnight. Through this process, the seed will develop thicker cells throughout its foliage so it is capable of regulating its temperature, water content, etc., with changing temperatures, wind, light, and humidity levels.
Step 5 - Transplant
Transplant your seedlings 8-12 inches apart to allow room for the rhizomes to develop.
Fall Canna Rhizome Removal
At the end of the growing season, you should cut the flower stalks down after a hard frost 4-6 inches from the soil surface. Dig up the tuberous rhizomes and store them inside until the following spring for planting. You should store them in a cool and dry environment (40-50 F preferred). Simply keeping them in a cardboard box is fine. If you live in zones 8+ you may overwinter your plants in the ground.