Canna lilies are popular garden plants known for their tropical foliage and vibrant blooms, often grown from rhizomes. They also produce hard, round seeds that can be collected and saved to grow new plants. Successfully storing these seeds requires careful attention to moisture and temperature to ensure they remain viable until planting time. Proper storage techniques mitigate the primary threats to seed longevity: fungal growth, metabolic decay, and insect damage.
Preparing Canna Seeds for Storage
Preparation begins immediately after harvesting the seeds from the dried, brown, and brittle seed pods. Seeds should be collected when the pods have fully matured, as immature seeds may not germinate reliably. Once collected, the hard, dark seeds must be removed from any remaining chaff or debris.
After cleaning, the most important preparatory step is thorough air drying, which significantly reduces the internal moisture content. High moisture levels encourage the growth of mold and fungus, which can quickly ruin stored seeds. Lay the seeds out in a single layer on a paper towel or newspaper in a cool, well-ventilated, and shaded location, away from direct sunlight.
Allow the seeds to dry for a minimum of a few days, and ideally for one to two weeks, to ensure all surface and internal moisture is removed. Although canna seeds have an exceptionally hard outer coat, this extended drying period is a necessary precaution. It guarantees the seeds are completely desiccated before they are sealed for storage.
Selecting the Ideal Storage Environment
The most effective storage environment for maintaining seed viability requires low temperature and low humidity. Storing seeds in a cool, dark location minimizes the rate of metabolic activity within the seed. This conserves the energy reserves needed for successful germination, with an ideal temperature range between 40°F and 50°F.
Many gardeners find a standard household refrigerator provides the consistent cool temperature needed for this purpose. A useful guideline for seed storage is that the temperature in Fahrenheit plus the relative humidity percentage should total less than 100. This formula highlights the need to manage both factors simultaneously.
For packaging, a small paper envelope or a breathable paper bag can be used if the storage area has very low humidity. For stable, long-term storage, the seeds are best kept in an airtight container, such as a small glass jar. This protects them from environmental humidity fluctuations. If using an airtight container, adding a small packet of silica gel or another desiccant material is beneficial to absorb any residual moisture.
Monitoring and Maintaining Seed Viability
Once the seeds are properly dried and packaged, the container should be clearly labeled with the canna variety and the date of collection. This labeling is important for planning the next planting season and tracking the seed’s age, as viability naturally declines over time. When stored correctly under cool, dry conditions, canna seeds can remain viable for several years.
Perform periodic checks on the stored seeds, perhaps once every few months. Inspect the seeds and the container for any signs of condensation, which indicates a moisture problem, or the presence of mold or pests. If moisture buildup is noticed, the seeds should be removed immediately, air-dried again for a few days, and then returned to a fresh, dry container.
If storing the seeds for more than one year, refrigeration is preferred to maintain longevity. Keeping the temperature consistently low and the environment dry maximizes the chance that the stored canna seeds will sprout when spring arrives.