August is when the character of the harvest changes. The flowers of high summer are giving way to seeds and berries, and beneath the ground the roots are beginning to pull their energy back down after the flowering season, concentrating their constituents in preparation for winter dormancy. This is the beginning of a different and in many ways more substantial harvest season than the lighter flowering herb work of June and July.
Seeds Worth Harvesting
Fennel seeds: harvest the seed heads when they are fully formed and the seeds are beginning to turn from green to brown-green. Snip the whole seed head into a paper bag and let them finish drying indoors before stripping the seeds from the stalks. Fennel seeds are one of the most useful digestive preparations and remain potent for up to two years when stored dry and cool.
Milk thistle seeds: the large, striped seeds in the thistle heads are ready when the cottony thistledown begins to form. Harvest the whole head before the down releases and dries open, put in a bag, and dry completely before processing. Grind fresh before use for maximum silymarin bioavailability.
Coriander seeds (also useful medicinally as a digestive carminative): harvest when the seeds are fully formed and beginning to dry on the plant.
Berries Worth Harvesting
Elderberries begin to ripen in August in most British and Northern European climates, hanging in flat-topped clusters of deep purple-black fruits. Test a few: ripe elderberries should be plump, dark, and separate easily from the stalk. Harvest the whole cluster and strip the berries from the stalks at home. Prepare syrup immediately from fresh berries or dry quickly for year-round use.
Rosehips are typically not ripe until September, but late-ripening varieties can be ready by mid-August in warm seasons. Look for the distinctive orange-red color and a slight softness to the touch. They are at their best after the first light frost, which sweetens them.
Roots: Beginning the Season
Elecampane roots are traditionally harvested in their second year in late summer or autumn when the plant is beginning to die back. Echinacea roots can be harvested from three-year-old plants in August. The general principle for roots is to harvest when the above-ground growth is dying back and energy is concentrated in the root. The Herbalist Codex app has specific harvest timing notes for all these plants alongside their medicinal profiles.