Geraniums (Pelargoniums) are a favorite for home gardeners seeking long-lasting color. Saving seeds from your favorite plants is a rewarding way to expand your collection without purchasing new seedlings each spring. This practice ensures a continued supply of your desired varieties or allows you to propagate plants with unique characteristics. Successful collection and storage require careful attention to the plant’s reproductive cycle and post-harvest conditions.
Identifying Mature Seed Pods
Recognizing the correct moment to harvest geranium seeds is important because the plant uses explosive seed dispersal. The seed capsule, which develops after the flower fades, is often called a “crane’s bill” due to its elongated, beak-like appearance. Initially, the pod is green and firm, indicating the seeds are still developing and not yet viable.
As seeds mature, the pod changes color, transitioning from green to tan, dark brown, or blackish. This darkening signals that the seeds are ripening and about to be ejected. Act quickly before the pod springs open; a slight lifting of the five outer segments from the central column indicates dispersal has begun.
Collecting and Curing the Seeds
To prevent the plant from launching its seeds, cover maturing pods with a small mesh bag or netting secured around the stem. When you observe the browning and slight opening of the pod, carefully cup your hand around the structure. Use small scissors to snip the stem below the pod, avoiding rough handling that could prematurely trigger the explosive release mechanism.
After collection, extract the seeds from the pod segments. This involves removing the fluffy, feather-like ‘tail’ or pappus attached to each seed. The pappus must be removed for storage, as it retains moisture and encourages mold growth. Spread the cleaned seeds in a single layer on a paper towel or plate in a cool, dry location out of direct sunlight for one to two weeks. This curing period reduces internal moisture content, which is necessary for long-term preservation.
Storing Seeds for Next Season
Long-term viability of geranium seeds requires a cool, dark, and dry environment. High heat and humidity are the primary enemies of stored seeds, causing premature germination or encouraging fungal pathogens. The ideal storage temperature is consistently cool, around 37 to 42 degrees Fahrenheit, often found in the back of a refrigerator.
Place the fully cured seeds inside small paper envelopes or tightly sealed glass jars to protect them from ambient moisture. Paper allows for air exchange, while a sealed jar better maintains a dry microclimate, especially with a small desiccant packet included. Labeling the container with the variety and year of collection is important to track seed age and prevent planting non-viable stock.
Maximizing Germination Success
Geranium seeds have a naturally hard outer shell, a protective adaptation that causes inconsistent or delayed germination. This tough seed coat prevents water absorption, keeping the seed dormant until conditions are favorable. Overcoming this physical barrier requires scarification, a process that artificially creates an opening in the shell.
Mechanical scarification involves gently rubbing the seed coat with fine-grit sandpaper or carefully nicking it with a small, sharp blade, ensuring the inner embryo is not damaged. Alternatively, soaking the seeds in warm water for 12 to 24 hours can soften the coat and speed up water penetration. Sow the seeds immediately after scarification to capitalize on the broken dormancy and increase the likelihood of a high germination rate.