Many species of mallows (commonly known as hibiscus) grow near or in water. Paper-like seed capsules are full of seeds with hard and buoyant coats. The seed falls to the water and drifts away. It is best to soak or scarify seeds to soften the coat before planting.
Blackberry lily seeds are encased in fruit. When eaten by an animal (bird, reptile, or mammal), the seed coat will be scarified in the digestive tract, readying it for germination. Otherwise, seeds will drop to the ground, the fruit will rot, and in that process, the seed will be exposed to the elements, which will soften the seed coat enough for germination.
In the case of milkweed seeds, feathery filaments are seemingly braided together. The pod will dry and crack, and the seeds’ plumes unfurl, separate and fly away.
To determine the best way to harvest seeds from garden herbs, flowers, or vegetables, it is helpful first to understand types of seeds and the varying dispersal strategies your plants possess. Depending on natural conditions and circumstances, plants have adapted over time to rely on wind, water, or animals to distribute their seeds far and wide. Dispersal methods are meant to ensure success in reproducing the next generation. By collecting and sowing seeds of your own garden, you can match a plant’s natural process, interrupt or speed up that process, and manage germination.
Click through these images to see plants with seeds dispersed by wind, animals or water.
We’ve all heard snipping the blooms on basil plants will keep the plants from becoming leggy, and deadheading blooms of sweet peas, zinnias, coneflowers and black-eyed Susans will give us re-bloom. Towards the end of the growing season, though, allow plenty of time before first frost for select plants to go to seed if you wish to collect and harvest seeds for the next growing season.
You must separate seed from filaments, capsules, or pods. To detach fly-away filaments, place seed heads in a paper bag with a few pebbles. Shake the bag. Peel open the bag to let the filaments fly away, pick out the pebbles, and you’ll be left with the seeds. For capsules and pods, when dry, pinch, roll, or pry open to remove seeds, then screen to separate seeds from remnants of capsules. For pulp-encased seeds, allow fruits and vegetables to fully ripen on the plant. Research the best method for harvesting wet seeds from particular plants. Some (including tomatoes) should be fermented to remove germination-inhibiting substances or to control growth of diseases. Artificial fermentation mimics the natural process of fermentation that occurs when the fruit is eaten by an animal or rots on the ground.
Carefully drying, sorting and storing seeds will help to ensure germination and growth of healthy plants when the next season rolls around. Again, it is important to mimic natural processes. Perennial wildflowers can be sown in the fall when they would naturally fall to the ground, germinate and over-winter in the garden. Some seeds will need to be stored in a refrigerator to match winter conditions. And some will just need to be stored in a dry, cool spot.
All plants are unique, and methods for collecting and harvesting, as well as preparations for planting should be researched for best practices.