This is just a short partial answer to a question !What to plant, Plant things you know you will use, plant things you need for recipes you wish to try and plant them all where they can be easily picked.
Leeks: more of a winter plant
Spinach: Originating in the middle east Spinach Spinacia oleracea Did not reach England until the 16th century. However, Silverbeet (or chard) Beta vulgaris var cicla and Orach Atriplex hotensis were used in the same way.
Beans: The common garden green bean Phaseolus sp, was a very late arrival in Europe and I would question it's use in any recipe before Columbus. However It is a really important and tasty summer garden crop. Broad beans Vicia faba and some beans belonging to the genus Vigna, which includes the cow pea, black eyed pea and snake bean were available during the SCA time period.
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