There's an absolutely gargantuan mountainside, with a peculiar climate. It has roughly a kilometer between where the woods stop and the snow falls, where an equally large priory ekes out a living. The various monks never leave the mountain, and live entirely on what they grow. What plants could exist here that can feed a large congregation of people, thrive on the rocky, barren soil, and persist with minimal rainfall?
As well as terracing and growing imported crops in protected environments within and around their monastery there would have been a lot to find in the high alpine valleys further afield. Provided there we’re not too many of them and they had scope to roam over a large enough area they should have been able to find enough food. Some are listed below from this reference http://edoc.unibas.ch/34764/
There are plenty of forgotten wild edible plants and in the past a lot more were probably used. Swiss alpine cantons, especially the canton of Valais, still have a viable tradition. And 98 edible plant species, which belong to 38 families, have been identified.
Plants were classified in eight categories based on the way they were traditionally used including salads, cooked vegetables, spices, alcoholic drinks, teas, syrups, jams, and raw snacks. The categories with the highest number of citations were teas (18%), followed by cooked vegetables (16%), jams (16%), and raw snacks (16%).
Taraxacum officinale, Sambucus nigra, Chenopodium bonus-henricus, and Urtica dioica were the most cited plants and most commonly used in the different valleys. Knowledge on edible plants is found from its origins in agriculture and activities as shepherds. Books written in the XIXth and early XXth centuries have documented these uses and have allowed identification of around 40 food plants, which had already fallen in oblivion (e.g. Bunium bulbocastanum). Two traditional edible plants (Phyteuma orbiculare and Cirsium spinosissimum) were submitted to a thorough phytochemical investigation.
The first species investigated was the round-headed rampion (Phyteuma orbiculare L., Campanulaceae). The sweet flowers of the plant were consumed by shepherds as raw snacks, whereas nutty-tasting leaves (rosettes) were eaten as a salad. 23 substances including different polyphenols, fatty acids, and triterpenes were identified from dried aerial parts. Phyteuma orbiculare contained interesting amounts of ascorbic acid, beta-carotene, polyphenols, polyinsaturated fatty acids, calcium, magnesium and potassium This food plant, which possesses interesting nutritive properties and favorable breeding predispositions, could be an interesting candidate for further agronomic development.
The second plant to be investigated was a thistle, Cirsium spinosissimum (Asteraceae). Surrounding leaves and the pappus hairs were removed before consumption, and the receptacle was eaten in early summer time. Taste of the receptacle is similar to that of an artichoke, and its consistency is tender. A total of 20 substances including polyphenols, a monoterpene lactone, fatty acids and a spermine derivative were identified.
This plant contains vitamins and polyunsaturated fatty acids in low amounts, and an interesting level of potassium. Cirsium spinosissimum is not really convenient for further cultivation due to its spiny morphology.
Other alpine edible plants selected during this work could be interesting with regard to their chemical composition, and for future breeding. They should be the main focus of further investigations. The establishment of alpine plants as new food crops would represent a diversification of the activities in mountain agriculture.
If the monks have been there for several generations, they have probably carved out terraces where soil can be collected and irrigated for farming.
If a warm humid wind usually breaks against the foot of the mountain. much of the wet air would push up along the face of the mountain, settling into the wind breaks caused by the terraces and shedding their moisture along the way. Wet wind which passes over the terraces would cool against the heights above, returning their water as condensation, dripping down the cliff face.
This wouldn't be the kind of farm where food just grows. It would be a work of man; productive only because monks regularly augment its natural resources with freshly composted earth and melted snow water.
If the monks work hard enough to keep the soil fertile, they could pretty much grow anything which can handle their mountainside micro-climate.
It has roughly a kilometer between where the woods stop and the snow falls
The fact that no trees grows in that area suggests that it can be an environment where lichens can grow. And of course they can be used as food, both for man and for animals.
Lichens are eaten by many different cultures across the world. Although some lichens are only eaten in times of famine, others are a staple food or even a delicacy. Two obstacles are often encountered when eating lichens: lichen polysaccharides are generally indigestible to humans, and lichens usually contain mildly toxic secondary compounds that should be removed before eating. Very few lichens are poisonous, but those high in vulpinic acid or usnic acid are toxic. Most poisonous lichens are yellow.
In the past Iceland moss (Cetraria islandica) was an important human food in northern Europe, and was cooked as a bread, porridge, pudding, soup, or salad. Wila (Bryoria fremontii) was an important food in parts of North America, where it was usually pitcooked. Northern peoples in North America and Siberia traditionally eat the partially digested reindeer lichen (Cladina spp.) after they remove it from the rumen of caribou or reindeer that have been killed. Rock tripe (Umbilicaria spp. and Lasalia spp.) is a lichen that has frequently been used as an emergency food in North America, and one species, Umbilicaria esculenta, is used in a variety of traditional Korean and Japanese foods.