Cabbage is a popular vegetable, with many varieties available for growing. In order to have a successful crop, it is important to save the seeds from your harvested cabbage heads. This ensures that you will get the same variety of cabbage that you planted in later years and allows you to share the seeds with other gardeners. Knowing how to harvest, prepare and store your cabbage seeds will make this much easier.
Where do Cabbage Seeds Come From?
As you know, white cabbage is a biennial plant. In the first year of life, the cabbage forms a cabbage head, but in order to get the seeds, it is necessary to leave this cabbage for winter storage. Moreover, during such storage, the cabbage must be stored at a temperature of up to 46ºF, since at this temperature growth processes are delayed, but at the same time, metabolism does not stop, which leads to the appearance of qualitatively new formations in the points of growth – the rudiments of flowers.
In the second year of life, the sprout is cut, and the remaining sprout is planted in the soil for rooting. If rooting is successful, long shoots with flowers collected in flower brushes grow from the core. The flowers in cabbage, of course, do not grow for beauty, but for the sake of usefulness alone, so they are small with only four yellow, cross-shaped petals. This arrangement of petals is what gave the second name to the cabbage family, the cruciferous plants.
When to Harvest Cabbage Seeds?
Once the cabbage crosses have fully bloomed, it is time to harvest. The petals of the flower should have already fallen off, and small seed pods will be visible in their place. When these seed pods are brown and dry, they are ready for harvesting.
How to Harvest Cabbage Seeds?
The best way to harvest cabbage seeds is to cut the seed head off of the plant and lay it out on a cloth or paper towel, away from direct sunlight. Let this sit for several days until the pods have completely dried out. Once dry, you can then carefully shake or brush off each pod, collecting the tiny black seeds.
Seed Preparation for Storage
Before storing the seeds, they need to be properly prepared. Spread them out on a clean cloth or paper towel and let them air dry for a few days. Once dry, you can use tweezers to pick out any foreign material that may have been harvested along with the seeds. Finally, you can place the seeds in an airtight container and store them at room temperature.
Storage Conditions
To ensure maximum seed viability, all cabbage seeds should be stored in a cool, dark, and dry area away from direct sunlight and moisture. Ideal storage conditions are around 40-50°F (4-10°C). The humidity for storage should be below 40%, and the air should remain circulated.
Longevity of Stored Seeds
Under optimal storage conditions, cabbage seeds can remain viable for up to 5 years with at least 14% germination rates. It is best to test the viability of your stored seeds every year or two by planting a few in damp paper towels and assessing the germination rate. If the seeds no longer show high rates of germination, it’s time to purchase new seed stock.
As depicted in the data below, longer storage times of seeds result in a proportional decrease in germination rates.
- 1 year – 85%
- 2 years – 75%
- 3 years – 59%
- 4 years – 54%
- 5 years – 14%