Buying new starter herbs each year can be costly. In the Bluegrass Region, it takes nothing but your time to learn how to identify when your herbs are seeding, to harvest those seeds for next years crop, and to dry and store the seeds.
Your herb garden has given you great pleasure from the planting of the first seeds, through the excitement of the first sprouts and continuing to the mature plant which you have enjoyed in so many ways. Now it’s time to think about next year’s herb garden and harvesting the seeds provided by your plant.
Identifying Seeds: Most herbs will begin to flower in mid-summer, attracting the insects they need for fertilization. Once this process has taken place the petals begin to drop revealing the seeds or seed pods. It is very important that you pay attention to your plant during this time if you desire to harvest the seeds. Many herbs are, by nature, self-seeding and can shed their seeds in a matter of days.
Seed Collecting Tips: If your herbs are in pots, the best way to harvest seeds is to gather sheets of white or light colored paper (I use unprinted newspaper – free from my local paper) so you can lay the herb on its side. With the plant on the paper, gently shake the plant allowing the seeds to fall. Many herb seeds like chamomile are tiny and this will aid you with seeing the seeds. Next you will need to remove any dried leaves or plant parts which have shaken loose. Spread the seeds on the paper to dry and place in a sunny area with little or no drafts.
If you have larger plants, you can spread sheets of newspaper under the plants and gently shake the seeds loose. Although most seeds can be easily harvested, many plants such as the mints are notorious self-seeders and will come back year after year.
An easier way to harvest seeds from larger herbs is to cut long flower stems and tie them with a rubber band, like you would to dry herb leaves. Then place the flower bunches upside down in paper sacks and in a few days shake the bunches to release the seeds. This method require the added step of bundling, but you don’t have to pick out as much plant “litter” from the seeds.
Drying Harvested Seeds: Drying seeds will take from 7 to 9 days and with larger seeds, possibly longer. When the seeds are dry, gently pour the seeds into glass jars or paper seed packets (small manila envelopes work great). Envelopes are preferable to glass jars for storage because they allow any moisture in the seed to evaporate naturally.
Spring Planting of Seeds: The seed of any plant is essentially what contains the plant’s DNA. Seeds have in them everything needed to start a new plant. In the spring, most seeds need a three to six week germination period to sprout. When the herbs have their first set of true leaves, they can then be transplanted into the garden or herb pots. There will be more articles of sowing and germinating seeds in the fall.