This is the fourth in a series of blogs, about ancient soil amendments used in the garden. Each blog will discuss a common and specific type of soil amendment used in the garden, along with documentation for its use, as well as occasionally discussing why a particular soil amendment was chosen, or its relation to modern gardening practices. The original blogs, along with other gardening related blogs, can be found here.

The use of food waste as a soil amendment is hardly ever specifically referred to in medieval and pre-medieval gardening texts. This might seem unusual – if you were to do a web search on what to do with your food waste right now, many of the first suggestions revolve around putting it into a compost or vermiculture bin. However, despite the lack of extensive specific references, it is probable this is what the medieval farmer did as well ( in addition of course, using it in a number of other ways).

First – it is safe to say there was probably very less food waste in the way we think of it now. The Forme of Cury specifically states to peel, or scrape, fruit or vegetables – but it is doubtful that such peelings went straight to the compost. There are medieval recipes that intentionally make use of modern waste items, such as entrails, and one of the easiest ways to make a broth heartier is to boil down left-over bits of vegetables (onion skins, celery tops and carrot ends) with bones.

Second, sometimes food waste was used to feed animals, much as it is now. Pigs and chickens are fairly non-discriminating with human food waste, so why would you simply throw old food out if you could use it to help feed your future food. Indeed, although pigs are cited in Geoponika as primarily eating acorns, and great forests are planted just for this purpose, later medieval farmers fed them food-waste.

Finally, we come to using food waste for compost or manure. In Geoponika, Florentinus shares that “some people dig a deep pit and cart all manure to it, the better with the worse, and rot it: into this goes … food waste” (p87). Havlicek, Pokorna and Zalesak (2017) talk about the creation of square pits which were used within cities as waste disposal sites much like the ones suggested by Florentinus. This advice, along with advice of Roman authors such as Varro and Columella would have been accessible to the medieval man. And though I am unaware of an explicit statement to use food waste in gardening during the medieval period, Richard Jones shares how it again becomes a stated practice during the post-medieval period.

Despite the lack of explicit statements however, it has long been assumed that the relatively few numbers of middens (Astill, G. Fields pp 63-85), (and how others are surprisingly small and seem to be poorly placed, suggest that most food waste was likely reused in some fashion. Additionally, the amount of pottery and bone found spread around fields and backyards suggests it was intentionally spread there (Pottery and Social Life in Medieval England, B. Jervis, 2014) – probably mixed with food waste – in an attempt to improve soils. Thus – it is safe to say, as a medieval gardener, should you want to turn your food waste into compost, you would not be out of the ordinary.

This is the third in a series of blogs, about ancient soil amendments used in the garden. Each blog will discuss a common and specific type of soil amendment used in the garden, along with documentation for its use, as well as occasionally discussing why a particular soil amendment was chosen, or its relation to modern gardening practices. The original blogs, along with other gardening related blogs, can be found here.

When discussing chaff in relation to soil amendments, it is important to understand what is meant. Chaff is an old word – from Old English ceaf, and in every definition it refers to the removed dry husks or shells of grains through the process of threshing and winnowing.

There is a detailed explanation in the Geoponika of which types of chaff are best to use in soil building from Varro, which mentions bean, barley and wheat husks (p88, Geoponika, trans. A. Dalby) used to help offset salty soil. This is interesting because Varro included bean husk as a type of chaff, where as other Cato separates the two.

Says Didymos in the same chapter (p89), chaff is okay for roots, but harmful to all manner of fruit, shoots, leaves and green vegetables (whose leaves it pierces). He warns to not place it upwind of farm buildings or pleasure gardens as well for it can cause eye-loss.

Cato talks of making a compost which includes straw, bean stalks and husks and “chaff” in Chapter 37, most likely meaning in this case, specifically grain chaff.

Of course, to use chaff as a soil additive straight would likely have been uncommon. Florentinus mentions ash from chaff in manure, but most other mentions within the Geoponika of chaff use it as a bedding for animals, feed for them, or storage substance (for a variety of foods including grapes and onions). The 15th century play Mankind shares the following proverb: “corn servit bredibus, chaffe horsibus, straw firybusque,” reminding us that chaff was supposed to be used as horse-feed.

Among other uses, Hamerow, Hollevoet and Vince (2016) discussed the use of chaff in Anglo-Saxon England to temper pottery. In Frederic Weaver’s book of Somerset Wills from the 14th and 15th centuries there are three instances of chaff-stuffed beds. In Medieval Merchant Ventures: Collected Studies, EM Carus-Wilson mentions a chaff-stuffed pillow. This practice continued into the 19th century, when the steps to fill the beds were outlined, and such beds were considered superior to straight straw. Finally chaff is even found in thatch and daub from medieval buildings (p43, Food in Medieval England: Diet and Nutrition).

Obviously chaff was used for so many other things, using it as a soil additive would only have been preferable if it was necessary – for instance, to help salty soil – or if the chaff was no longer useful for any other thing.