The herbs as well as the officinal ones they should always be harvested on days of dry weather, early in the morning and dried in the shade in well-ventilated areas. This should be a good rule of thumb if you want to keep them for a long time.
Pay attention to humidity and light. The herbs they keep well once dried if they are kept dry away from direct light and better if in low light; the pantry and cellar are fine for the purpose.
Inflorescences or leaves? In the case of herbs of which you want to keep the inflorescences (oregano, thyme, marjoram ...) you can collect a bunch of stems about 20 centimeters long and wrap it in newsprint, or in bread paper, and then hang it upside down in a spot in the shade and well ventilated. Once dry, it becomes easy to crumble the flowers and collect them in jars.
Of the herbs of which you want the leaves (mint, tarragon, rue…) it is good to harvest them before flowering (removing the leaves without removing the stem) and drying them on racks exposed to the sun. It is good to turn the leaves often to facilitate the drying process. Once ready, these can also be stored in glass jars in a dry and dark place.
The herbs most used in cooking and often used to preserve are: dill, basil, coriander, watercress, chives, marjoram, lemon balm, mint, oregano, parsley, rosemary, sage, savory and thyme.
The most suitable period for the collection of almost all herbs it runs from June to July, which is also the period in which the seedlings reach their maximum vigor and allow for successful multiplication by cuttings. The sun and the high temperatures of these months are also ideal for drying.
Herbs and spices. In truth, the distinction is not so clear and often also in the texts it happens to find different lists or the same essences in both lists. A good indication is given by popular language, which defines aromatic herbs (such as basil, parsley, mint ...) as 'smells', while retaining the typical indication for spices (pepper, saffron, cloves ...). But maybe that's not enough.
To better identify the difference we can say that of the herbs mainly the leaves or at most the flowers are consumed, often fresh and less often after drying (which in fact causes them to lose a little) while spices (which in turn are characterized by the aromatic principles they contain) are used also seeds, roots, bark etc.
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