Introduction

Roman and medieval communities dedicated much of their time to acquire, produce, process and prepare food which varied according to their various habits, daily routines, social and religious customs and tastes. Plants seem to have occupied a fundamental role in the mundane and ordinary tasks of everyday life. This was particularly true for the people living in the countryside whose daily work must have been governed by the rhythms of agricultural tasks, the care of crops, the gathering of wild plants and the repetitive activities related to processing and preparing food. Plant remains provide a way of exploring and understanding various aspects of the human experience, including food strategies, technological changes, social interactions and power relations (Montanari 2008; Woolgar 2010; Twiss 2012; Chevalier et al. 2014; Hastorf 2017; van der Veen 2018). But plant remains can also inform about their arrival from distant places, of adaptation, innovation and also of choices. Their histories are thus of interest to reconstruct the social and economic conditions of the communities where they were used.

Despite their importance for offering interesting insights into many aspects of Roman and medieval life, there has not been much interest among Iberian specialists in the plants of the 1st millennium ce, with the exception of those (mostly philologists) specialized in the rich evidence from the Islamic botanical and medical texts. Of particular significance is the work of E. García who was responsible for the series Ciencias de la Naturaleza en Al-Andalus (Natural Sciences in Al-Andalus, the parts of Iberia under Muslim rule) published by the CSIC (García Sánchez 1983, 1990, 1992, 1994, 1996, 1998, 2001, 2004, 2014; García Sánchez and Hernández Bermejo 2007), as well as the research carried out by many others such as J. Carabaza (Carabaza Bravo 1991, 2018), Camarero (Camarero Castellano 2008) and J.M. Millás (Millás Vallicrosa 1955) or M. Marín and colleagues (Marín 1990, 2000; Marín and Waines 1994; Marín and de la Puente 2005) on the culinary practices in Al-Andalus. Moreover, apart from some important cases (Alonso et al. 2014; Teira Brión 2022; Teira Brión et al. 2023; Tereso 2009; Tereso et al. 2013a; Vigil-Escalera Guirado et al. 2014; Ros et al. 2018; Peña-Chocarro et al. 2019b; Peña-Chocarro and Pérez-Jordà 2019; Seabra et al. 2022a, b, 2023a), neither have Roman or medieval archaeologists demonstrated particular enthusiasm towards integrating archaeobotany into their research projects, denying the potential that can be unlocked through the study of plant remains. Thus, current knowledge of what plants people actually produced, gathered and ate in Iberia during the 1st millennium ce is essentially based on:

  1. a)

    Information contained in different types of written sources such as the works of Latin authors on agriculture such as Cato, On Agriculture (Hooper 1993), Varro On Agriculture (Hooper 1993), Columella Los Doce Libros de Agricultura (Álvarez de Sotomayor y Rubio 1979) or Pliny, Natural History (Rackham 1968), who wrote mostly for the Roman elites describing types of cultivation, crops or agricultural tasks and processes. For the medieval period there are archival sources including a wide variety of documents such as Christian records, mostly from ecclesiastical institutions and mainly represented by the legal records of property transfers. These provide information on agricultural produce or its use as payments and valuation in kind (Davies 2002) and on land use of the transferred areas of land and agricultural infrastructure, such as water mills. These texts contain valuable information on agricultural practices and the strategies of farmers as well as on the growing and consumption of some commodities such as cereals, wine and fruits. In many cases, however, plants are classified under rather general categories such as legumes, cereals, or fruits, which limit the possibility of grasping the details of the plants involved, their growing cycles or processing requirements, and ultimately the choices made by people. On the other hand, the written records of Al-Andalus are extremely limited. The bulk of the available texts are chronicles, geographical and legal works, bio-bibliographical dictionaries, religious biographies, poetry and literature, and scientific works (Guichard 1999; Torró 2012). Far more interesting and useful for studying farming and food issues is the important collection of agricultural and medical treatises translated and/or published to a large extent, but not exclusively, by colleagues from the CSIC (see bibliography above). Over the past decades, these researchers, supported by a robust philological approach, have translated and studied numerous Islamic texts dedicated to food, medicine and agriculture, contributing enormously to a great advance in the knowledge of Islamic science and agricultural practice.

  2. b)

    A limited number of archaeobotanical studies from both periods which in most cases result from particular initiatives. The number of Roman sites studied is very small and the latest advances come from Portugal (Tereso 2009; Tereso et al. 2013a, c, 2020; Tereso and Cruz 2014; Vaz et al. 2016, 2021; López-Dóriga 2020; Seabra et al. 2022a, b, 2023a, b) and Galicia (Teira Brión 2010, 2019, 2022; Tereso et al. 2013b), while some work has been also carried out in the rest of the Iberian peninsula (Peña-Chocarro and Zapata 1996, 1997, 2005; Alonso 2005, 2008; Alonso et al. 2010, 2014; Rodríguez-Ariza and Montes Moya 2010; Montes Moya 2014; Voropaeva and Stika 2018; Peña-Chocarro et al. 2019a). More recently, two papers have provided a general overview of the archaeobotanical results for this period (Peña-Chocarro et al. 2019b, Peña-Chocarro and Pérez-Jordà in press). For the last part of the 1st millennium ce, the development of medieval archaeology over the past three decades has allowed the excavation of considerable number of sites across the Iberian Peninsula, but without integrating archaeobotany in the research programs except for a small number of archaeobotanical studies (see references above). More recently, the field of agrarian archaeology has started with a focus on landscapes, which are providing highly interesting information on the management of crop fields and related issues (Ballesteros Arias et al. 2010; Kirchner 2010; Fernández Mier et al. 2014; Quirós Castillo 2014; Quirós Castillo et al. 2014).

Nevertheless, despite these rather few advances, the study of plant remains in Iberia has been largely overlooked. This situation greatly differs from that of most other European and some Near Eastern countries where the development of Roman and medieval archaeology has been accompanied by a significant expansion of environmental archaeology, and in particular of archaeobotany. In countries like France (Ruas et al. 2005, 2015; Bonnaire et al. 2010; Ros et al. 2020), Ireland (McClatchie et al. 2015), the UK (Moffett 2006; Lodwick 2018; McKerracher 2018; Hamerow et al. 2019, 2020), Italy (Buonincontri et al. 2014, 2017; Rottoli 2014; Primavera 2018) or the Near East (Samuel 2001; Amichay et al. 2019; Fuks et al. 2020) to quote just a few, the archaeobotanical results on the 1st millennium ce have provided interesting insights into diet and plant resource use, fuelling the debate of the development of farming during the Roman and the medieval periods. For an excellent overview, see Lodwick and Rowan (2022).

Methodology, sites and contexts

A recent publication coordinated by the authors (Peña-Chocarro et al. 2019b) has assembled records from 83 published and unpublished sites across Spain and Portugal dated to the Roman and medieval periods, which represents the first corpus of archaeobotanical data from the 1st millennium ce in this region. Based on this paper, on those published afterwards (Ros et al. 2019; Teira Brión 2019, 2022; Lityńska-Zając and Rębkowski 2020; Quirós Castillo et al. 2020; Seabra et al. 2020, 2022a, b, 2023a, b; Tereso et al. 2020; Teira Brión et al. 2023) and on additional unpublished archaeobotanical data from various sites across Iberia studied by the authors, this paper focuses on the plants that were grown or gathered in the Iberian Peninsula during the 1st millennium ce. Particular emphasis is given to the new crops that appeared for the first time in Iberia during this long period.

The data considered in this paper come in most cases from systematic flotation of plant macroremains at the various sites, although some are from hand-picked samples collected during the course of the site excavation. In this paper we concentrate on the first presence of particular taxa and so no information is provided on sample size, subsampling or the total number of samples or items in each sample, which can be found in the original publications. Sites mentioned in the text mainly correspond to those where the taxa discussed have been identified from sites in Iberia dated within the 1st millennium ce. In some cases (see below) the first evidence of a particular plant comes from the beginning of the following millennium (11th-13th centuries), but it has been decided to include these in this review because of the importance of the taxa concerned (Fig. 1; Table 1).

Fig. 1
figure 1

Map showing the sites mentioned in the text. (1) L’Esquerda, (2) Vilauba, (3) Can Gelats, (4) Camp Vermell, (5) Roc d’Enclar, (6) Balaguer, (7) Las Sillas, (8) Ilerda, (9) Bovalar, (10) Cabezo de la Cisterna, 11. El Quemao, 12. Benaxuai, 13. Pago de El Jarafí, 14. La Gabia, 15. Cueva de la Dehesilla, 16. Mértola, 17. La Ayuela, 18. Albalat, 19. Melque, 20. Carranque, 21. Acedinos, 22. Gózquez, 23. Risco de las Cuevas, 24. Senhora do Barrocal, 25. Monte Mozinho, 26. Freixo/Tongobriga, 27. Crasto de Palheiros, 28. Crastoeiro, 29. Terronha de Pinhovelo, 30. O Areal, 31. Castrolandín, 32. O Bordel, 33. Castro Arxeriz, 34. Castrovite, 35. Castromaior, 36. Tabacalera, 37. El Picón, 38. Castrillo Mota de Judíos, 39. Vitoria/Gasteiz, 40. Irun, 41. La Noguera, 42. Bureta, 43. Ambel, 44. La Mora Encantada

Full size image
Table 1 Sites mentioned in the text, with chronology, type of preservation of the plant material, recovery technique and reference for each site
Full size table

What do we know about 1st millennium ce plant use in Iberia?

As already mentioned, archaeobotanical data are scarce but they suggest that Roman and medieval communities cultivated a wide variety of cereals, legumes, vegetables and fruits which represented their main foodstuffs. During the Roman period several new crops were introduced or at least cultivated and widely spread throughout the peninsula. This is the case of crops such as Secale cereale (rye), Phoenix dactylifera (date palm) and others such as Prunus persica (peach), Morus nigra (black mulberry) and several herbs and spices like Rosmarinus officinalis (rosemary), Mentha spp. (mints), Apium graveolens (celery) and Brassica spp. (cabbages and mustards etc.) which made their first appearance in Roman sites (Peña-Chocarro et al. 2019b).

Exploring plant diversity in medieval Iberia necessarily involves an assessment of the introduction and/or spread of new crops during the Islamic period (Watson 1974). In his seminal work, The Arab Agricultural Revolution, later expanded and reformulated (Watson 1981, 1983), Watson laid the foundation for the widespread idea of a “medieval green agricultural revolution” which occurred between the 7th and the 11th centuries ce after the unprecedented unification by the Arabs of a huge area stretching from regions of Central Asia to the Iberian Peninsula. These circumstances would have allowed the circulation not only of people and ideas, but also of technical knowledge and goods, amongst which crops occupied a central place in Watson’s model. A total of 18 species, mostly foods but also fibre crops, were chosen as examples of crop diffusion, Oryza sativa (rice), Sorghum bicolor (sorghum), Triticum durum (hard wheat), Citrullus lanatus (watermelon), Solanum melongena (eggplant), Gossypium hirsutum (cotton), Saccharum spp. (sugar cane), Cynara cardunculus (globe artichoke), Spinacia oleracea (spinach), Colocasia esculenta (taro etc.), Citrus × aurantium (bitter or Seville orange), C. limon (lemon), Citrus spp. (lime), Musa acuminata (banana), M. × paradisiaca (cooking banana), Mangofera indica (mango) and Cocos nucifera (coconut). Some were already suitable for growing in dry areas, while others needed technical solutions such as irrigation. The model has been criticized for inaccuracies in the attribution of some introductions to the Arabs (Decker 2009). One of the crops under scrutiny is Triticum durum (durum wheat) which was present in Iberia since the Neolithic (Peña-Chocarro et al. 2018) as well as in other parts of Europe (Kirleis and Fischer 2014), and it was present in North Africa (Morales et al. 2013) and the Near East (Fairbairn et al. 2002) already in prehistoric times. Oryza sativa (rice) is another crop which was thought to have been introduced by the Arabs, but archaeobotanical data suggests that by the Roman period rice was being already traded across the Mediterranean, and also appearing in several sites in central Europe (Muthukumaran 2014). Decker (2009) also includes cotton which has been found in pre-Islamic levels of sites in North Africa and the Near East and Cynara scolymus (globe artichoke), which was widely cultivated in Roman times according to written sources. Nevertheless, whether some taxa may have already been present in some of the regions under scrutiny does not invalidate the role that Islamic communities had in their spreading of crops and bringing them to new regions, favouring their adaptation to different environments (Squatriti 2014).

Useful evidence has been obtained from a particular interesting type of site, cliff granaries, which are found in remote parts of several regions of Iberia (Andalucía, central Spain, Valencia, upper Ebro valley) are providing exciting desiccated plant material which can offer excellent insights into the variety of crops cultivated at the time when they were deposited there. Cliff granaries are inaccessible artificial caves which appear as groups of openings cut into cliff faces that were used by the Islamic people for storing food and probably other items. In some cases, there are visible remnants of external structures such as stone or brick walls and wooden platforms. The interiors consist of series of connecting chambers which sometimes preserve material such as pottery, parchment remains, wooden objects, textile fragments, animal bones etc. (Ribera i Gómez 2010). Recent proposals link these cavities to the management and storage of agricultural products (Ribera i Gómez 2016). The use of these cliff granaries in Iberia appear to be closely connected with the arrival of the first North Africans during the Islamic conquest. In fact, Iberian cliff granaries have astonishing parallels in North Africa, where several examples exist in the Moroccan Atlas and Anti-Atlas regions (Gattefossé 1934). Perhaps, the most important aspect of these features is that due to the extreme dryness of the interior of these caves, extraordinary desiccated archaeobotanical material such as complete cereal ears, grains, chaff, grapes, seeds and fruit stones have been preserved. These materials include taxa and remains that are not usually preserved by charring. Such desiccated remains found buried in the sediment or trapped in the wall plaster, and also as part of daub, offer a unique opportunity not only to explore crop diversity but also to carry out genomic analyses. The samples collected have been checked for aDNA (ancient DNA) yielding positive results (Royo unpublished data). Similar features have been studied in Gran Canaria with contexts dated to the 6th-15th centuries ce (Morales et al. 2014; Henríquez-Valido et al. 2019) from which aDNA has also been recovered (Oliveira et al. 2012; Hagenblad et al. 2017; Hagenblad and Morales 2020), affording interesting insights into the archaeology of these plants.

Cereals

During the 1st millennium ce, cereals were the main food plants. A range of wheat and barley species that had been grown since the Neolithic (Pérez-Jordà 2013; Antolín 2016; Peña-Chocarro et al. 2018) continued to be cultivated during the 1st millennium ce. This cereal ‟package” was dominated by Triticum aestivum and T. durum (free-threshing wheats) and Hordeum vulgare ssp. vulgare (hulled barley) which were the staple crops. Both grains and chaff of these, the commonest cereals, have been retrieved from all over the peninsula. Other cereals, such as the hulled wheats, namely T. monococcum (einkorn), T. dicoccum (emmer) and T. spelta (spelt) were also grown, although much less than the free-threshing wheats. Their presence is uneven in Iberia, where they only appear occasionally as a secondary or residual crop in a few sites (Peña-Chocarro et al. 2019b). An exception is represented by northwest Iberia, where emmer and spelt seem to have played a significant role, particularly during the Iron Age. They appear in several sites in Galicia such as Castrovite and Castrolandín (Teira Brión 2019), Castromaior and Castro Arxeriz (Peña-Chocarro in prep.), and in Portugal, such as Crastoeiro (Seabra et al. 2018), Terronha de Pinhovelo (Tereso 2009) or Crasto de Palheiros (Tereso et al. 2013a), among others.

Secale cereale(rye)

Rye is one of the cereals that spread into Iberia during the 1st millennium ce (Fig. 2; Table 2). The earliest evidence comes from several Iron Age sites in Portugal (Seabra et al. 2018, 2023a, b). Six radiocarbon dates on grains place its introduction between the 3rd and 1st centuries bce (D-AMS 2,139 ± 20, 350 − 55 bce; D-AMS 016318 2,132 ± 31, 350 − 40 bce; D-AMS 011304 2,027 ± 25, 100 bce-70 ce; Beta-596,126 2,120 ± 30, 350 − 40 bce; D-AMS 047814 2,158 ± 21, 355 − 105 bce; D-AMS 042655 2,062 ± 22, 155 bce-10 ce). Recent research (Seabra et al. 2023a) suggests that this early presence of rye represents weedy forms that would have grown in fields of hulled wheat, especially spelt crops. They also point to the fact that when spelt disappeared during the 1st century ce, rye also vanished. Later sites such as Monte Mozinho (Tereso et al. 2013c), Tongobriga (Seabra et al. 2023a) in Portugal, or Vilauba (Colominas et al. 2019), Ilerda (Alonso 2005) in Catalonia, Castromaior in Galicia (authors’ unpublished data) and El Picón (Zamora) (authors’ unpublished data) have also produced rye dated between the 2nd and the 4th centuries ce. In fact, the spread of rye is associated with the Roman period in Hispania (Iberia), as it was introduced then. However, evidence of its cultivation in Spain is scarce and it seems, at least during the Roman period, to have been concentrated in northwestern Iberia with a few examples in the northeastern part (sites of Vilauba and Ilerda). This regional distribution may perhaps be related to the better adaptation of the rye to the poor soils and adverse climatic conditions which characterize the northwestern part of Iberia. Later on, during the 5th century ce, rye was still cultivated in the northeast and from the 6th century it appears from many more sites in this area such as Roc d’Enclar (Andorra) (Buxó 1997), Bovalar (Lleida) (Cubero i Corpas 1988), Vilauba (Girona) (Colominas et al. 2019) and Can Gelats (Girona) (Peña-Chocarro et al. 2019b), but also in central Spain from the sites of Gózquez (Madrid) (Vigil-Escalera Guirado et al. 2014), Melque (Caballero Zoreda et al. 1999), Acedinos (Madrid) (authors’ unpublished data) and Carranque (Toledo) (authors’ unpublished data) where its presence is more limited. In Portugal, several sites have also yielded rye from this period (Seabra et al. 2023a).

Fig. 2
figure 3

Plant remains introduced in Iberia during the 1st and beginning of the 2nd millennium; a Pennisetum glaucum; b Secale cereale; c Oryza sativa; d Cannabis sativa; e Cydonia oblonga; f Mespilus germanica

Full size image
Table 2 Crop introductions during the 1st millennium ce and the first centuries of the 2nd millennium ce in Iberia
Full size table

Rye became more frequent in medieval times, showing a much wider distribution in both Christian and Islamic sites. It has also been found in northeast Iberia from the sites of Camp Vermell (Andorra) (Alonso et al. 2010), L’Esquerda (Barcelona) (Cubero i Corpas et al. 2008) and Las Sillas (Ros et al. 2019) and from various sites in Aragon (Treasure 2020). In northern Spain it is also found from sites of Vitoria, in the País Vasco (Basque Country) (Zapata and Ruiz-Alonso 2013) and in La Noguera farmstead (La Rioja) (López de Calle et al. 2019), in central Spain at the Jewish site of Castrillo Mota de Judíos (Burgos) (authors’ unpublished data), in Extremadura at Albalat (Cáceres) (Ros et al. 2018), in Andalucía from Pago de El Jarafí (Granada) (authors’ unpublished data) and from several sites across Portugal such as Senhora do Barrocal (Seabra et al. 2022b). Despite its presence in many regions, the number of remains is low, perhaps indicating that rye was never widely grown. It is likely that its survival up to recent times in mountainous areas where it is one of the main crops responds to a tradition dating back to the Roman period. Surprisingly, rye has been found in several Islamic sites in the form of desiccated complete ears (grain is absent in most cases) from two cliff granaries (see below) in the provinces of Madrid (Risco de las Cuevas) and Valencia (Cueva de Benaxuai) (authors’ unpublished data).

Millets: the case of Pennisetum glaucum (pearl millet)

During the 1st millennium ce, millets were also widely cultivated in Iberia, particularly in the northwest. Two species, Panicum miliaceum (common millet) and Setaria italica (foxtail millet) were mainly grown. They appeared for the first time in the archaeological record of Iberia during the Bronze Age, but it is during the Iron Age when their cultivation was fully established.

Most recently (work in progress), a new millet species, Pennisetum glaucum (pearl millet) has been identified from Islamic contexts. Complete ears and grains preserved by desiccation have been identified from several Islamic sites in Valencia (Benaxuai cave) (Fig. 2), charred in Granada province (authors’ unpublished data) and by mineralization in Córdoba province (authors’ unpublished data). Although the pearl millet has been dated to the 11th-12th centuries ce (Table 2) we have decided to include this crop in our synthesis because it is likely that it was introduced into Iberia before then, during the 1st millennium ce. This is the first evidence of this species in the western Mediterranean and as far as we know, also in Europe. It seems clear that P. glaucum was domesticated in the Sahel zone of West Africa around the mid 3rd millennium bce, and from there it spread throughout the Sahara region and then into India (Fuller et al. 2021). How it arrived in Iberia is still unknown. In this regard, it is interesting to note that medieval documents from the Valencia region regularly refer to different types of cereals, among which there is a crop named dacsa. Various authors working with these documents have identified this crop as Sorghum bicolor (sorghum) (Alpera 1968) but information is still patchy and the word dacsa may well refer to pearl millet instead (work in progress).

Oryza sativa(rice)

A further introduction of this period is Oryza sativa (rice) which was brought into the Iberian peninsula in the Islamic period (Watson 1981, 1983). In fact, the cultivation of rice in Islamic Spain is already mentioned in the 10th century Cordoba Calendar, a fascinating work which includes meteorological, astronomical and associated agricultural matters (Rincón Álvarez 2003). During the 11th and 12th centuries, agronomists from Al-Andalus such as Ibn Bassal (Millás Vallicrosa 1955), Abu Jayr (Carabaza Bravo 1991), Ibn Al-Awwam or Ibn Luyun (Eguaras Ibáñez 1988) described the methods used for growing rice, providing details on its sowing, the best areas for its cultivation, both under irrigation and on dry land, transplantation and harvesting in September. Despite the finding of rice from several Roman and medieval contexts across Europe (Konen 1999; Zach 2002; Livarda and van der Veen 2008; Reed and Leleković 2019), the only archaeobotanical evidence from Iberia is represented by a single fragmented desiccated hulled rice grain retrieved from the Benaxuai cave in the Valencia region (authors’ unpublished data) dated to the 11th-12th centuries ce (Fig. 2; Table 2).

Legumes

The available data suggests that farmers continued to grow the same variety of legumes as in prehistoric times: Vicia faba (broad bean), Pisum sativum (pea), Lens culinaris (lentil), Lathyrus sativus (grass pea) and several vetches such as Vicia sativa (common vetch) and V. ervilia (bitter vetch) (Pérez-Jordà 2013; Antolín 2016; Peña-Chocarro et al. 2018). As for Cicer arietinum (chickpea), its presence is less common. It has been only found from a couple of sites, La Gabia attributed to the Roman period (Montes Moya 2014) and the medieval site of L’Esquerda (Cubero i Corpas et al. 2008). More recently, chickpea remains have been identified in Extremadura from the site of La Ayuela (authors’ unpublished data). There is no evidence of Lupinus (lupin) or Vigna unguiculata (cow pea).

Fruit

Fruit and nuts were a source of sugars, vitamins, minerals and fibre providing diversity to the usual diet. Many of the taxa already known from the Iron Age were also grown during the 1st millennium ce, such as Prunus armeniaca (apricot), Juglans regia (walnut), Malus pumila (apple), Pyrus communis (pear) Punica granatum (pomegranate), Vitis vinifera (grapevine), Ficus carica (fig) etc. (Pérez-Jordà 2013; Alonso et al. 2016; Pérez-Jordà 2021a, 2021b). Archaeobotanical data from the Roman and medieval periods shows an enormous diversity: grape, fig, Olea europaea (olive), Phoenix dactylifera (date), apple, Prunus persica (peach), P. avium and cerasus (sweet and sour cherry), P. domestica (plum), pomegranate, Morus nigra (black mulberry), Cucumis melo var. flexuosus (Armenian cucumber, alficoz), P. dulcis (almond), Cydonia oblonga (quince), Mespilus germanica (medlar), citrus fruits, walnut, Castanea sativa (chestnut) and almond have been documented (Peña-Chocarro et al. 2019b). Of these, peach, apricot, black mulberry, quince, medlar, date and citrus fruits were possibly introduced in either the Roman or the Islamic period during the 1st millennium ce (Table 2).

The first evidence of peach in Iberia comes from the Roman levels (1st-2nd centuries ce) of the site of Irun (Pais Vasco) where hundreds of stones were found in waterlogged levels of the ancient Roman harbour that most probably represented imports (Peña-Chocarro and Zapata 2005). Remains of similar date were also recovered from Catalunya (Canal et al. 2004), Galicia (Teira Brión 2022), Andalucía (Peña-Chocarro et al. 2019b) and northern Portugal (Fernando de Almeida and da Veiga Ferreira 1967), while later finds are also reported from sites both in Portugal (Vaz et al. 2016) and Spain (Treasure 2020; Teira Brión 2022). Other members of the Rosaceae family such as Prunus domestica (plum), of which several varieties have been identified, only appeared from the Roman period onwards, while almond, sweet and sour cherries and apple were also present in the late 1st millennium bce. Several different Prunus spp. have also been found from several medieval sites in Iberia.

The black mulberry, however, seems to be a Roman introduction. It has been identified in Galicia from the site of O Areal (Teira Brión 2022), and later from Vilauba (Girona) (Colominas et al. 2019). It was also found from several medieval Islamic sites in Aragón (Treasure 2020) such as Cabezo de la Cisterna and El Quemao in Teruel province, and in Bureta, La Mora Encantada and Ambel in Zaragoza province. Morus nigra also appeared in Albalat in Cáceres province (Ros et al. 2018). Dates also appear also for the first time in Roman levels (mid 1st-3rd century ce) as an offering in the Temple of Isis (Cádiz province) (Ruas 2008).

The Islamic period brought many novelties not only related to the variety of fruit plants but also to sophisticated grafting techniques and new ways of growing and managing crops such as by irrigation. Textual sources, mostly agricultural treatises written by Hispano-Arab agronomists, include a great diversity of plants among which fruit trees are an important component. Information is provided on methods of planting and cultivation, grafting and on the right seasons for carrying out specific tasks such as manuring, watering, pruning, storage etc., as well as on consumption and uses. Other textual sources provide information on specific plant varieties.

Most of the fruits listed by Watson (1974, 1981, 1983) are absent from the archaeobotanical record of Iberia, probably because the number of Islamic sites analysed is still so limited, but also because some of these plants were introduced to the region much later. There are, however, some data about some new fruit taxa which started to be grown in this period, for instance, Prunus armeniaca (apricot), which is recorded for the first time from Islamic contexts in southern Portugal (Pais 1996). Also of interest is the finding of the first remains of Cydonia oblonga (quince) in southwest Spain from the very beginning of the 11th century ce at cueva La Dehesilla (Cádiz) (García-Rivero et al. 2018) (Fig. 2). Mespilus germanica (medlar) has been identified from Pago de El Jarafí (Granada) (authors’ unpublished data), southern Spain from between the 8th and 12th centuries ce and at O Bordel (A Coruña), north-western Iberia dated to the 11th-12th centuries ce (Fig. 2; Teira-Brión et al. 2023).

Perhaps the most significant finds are those of citrus fruits from the site of Mertola (southern Portugal) from a context of the 11th century ce (authors’ unpublished data). Citrus was already known in the Mediterranean in Roman times, and several classical authors mention Citrus medica (scented citron) which appears to have been the first citrus fruit introduced into Europe. Archaeobotanical data seem to support this hypothesis (Pagnoux et al. 2013). Between the 10th and the 11th centuries ce various Hispano-Arab agronomists mentioned several citrus fruits other than the citron in their texts. These are the Citrus limon (lemon), C. aurantiifolia (lime), C. maxima (pomelo or shaddock) and C. aurantium (bitter or Seville orange) (Ramon-Laca 2003).

The oriental origin of most of the plants listed by Watson is clear, but an issue that has never been addressed is the likely introduction of new varieties of crops already cultivated in Europe or North Africa. In 1981, Watson inquired about the agents responsible for the introduction of new plants, suggesting that these could have been rulers interested in obtaining exotic plants for their gardens or elites importing plants for commercial use. He also put forward the possibility that farmers may have brought their own crops or crop varieties to the conquered areas, either because they were familiar with them, or because of their specific value. Islamic sources are almost silent in this regard, but there are some examples of the mention of novel varieties being introduced. A particular case is the description of the bringing from Damascus to Córdoba, under Abd al-Rahman I, the first emir of Córdoba, of a variety of pomegranate known as safarí, which is still cultivated today (Samsó 1981–1982; Glick 2005). Other examples may be the doñegal fig or even some palm varieties (Nabhan 2014).

Vegetables, herbs and spices

The archaeobotanical record of what can be considered garden plants in Iberia is rather limited for the 1st millennium ce. In most cases, the scarce information comes from waterlogged sites where these plants represent a small part of the botanical assemblage (Peña-Chocarro et al. 2019b; Peña-Chocarro and Pérez-Jordà 2019). Gardens contained many plant categories such as food and medicinal plants, spices, herbs, dye plants, ornamentals and those producing useful materials for crafts, etc. Legumes, fruits, vegetables, tubers, etc. were grown in these gardens, contributing to diversity in the diet but also producing raw material for various purposes. Previous work (Peña-Chocarro et al. 2019b; Peña-Chocarro and Pérez-Jordà 2019) shows the presence of various herbs and flavourings, such as Rosmarinus officinalis (rosemary), Mentha spp. (mints), Coriandrum sativum (coriander), Apium graveolens (celery), Foeniculum vulgare (fennel), Verbena officinalis (common vervain) and Lavandula spp. (lavender) in Roman and medieval times. Moreover, vegetables such as several Brassica spp. (cabbages and mustards) were also present, while Daucus carota (carrot) has been also recovered from several sites across Iberia dated to the Roman period or later. From the medieval period, Nigella spp. (black caraway), Allium sativum (garlic) and Brassica rapa (turnip, etc.) appear for the first time in Iberia (Alonso et al. 2014; Treasure 2020; Teira Brión et al. 2023) (Table 2). One of the big issues when discussing garden crops, particularly when the dataset is limited, relates to the difficulty of deciding whether these plants may have been used for human consumption or if they represent wild plants. Despite the significance of the plant taxa identified in the archaeological record, it is clear that the actual diversity of garden plants must have been much wider, as the Hispano-Arab agronomic literature suggests.

Fibre crops

Flax (Linum usitatissimum) is well known in Iberia since the Neolithic and continued to be cultivated throughout the 1st millennium ce either for its fibres or for its oil or both. In contrast to the results from central and eastern Europe, there is little evidence of the cultivation of Camelina sativa (gold of pleasure). Its seeds are present from the 1st millennium bce (Pérez-Jordà 2013) but it is difficult to ascertain whether these come from wild specimens. Seeds were also retrieved from the medieval Islamic layers of Lleida and Balaguer (Alonso et al. 2014) and from several Islamic sites in Aragon (north-east Spain) (Treasure 2020).

Desiccated seeds from a third fibre crop, Cannabis sativa (hemp), have been recently identified from Islamic sites near Madrid (Risco de las Cuevas) and Valencia (Benaxuai cave) (authors’ unpublished data) (Fig. 2). Although there is evidence of its cultivation in other parts of Europe from the late Iron Age (Bouby 2002) or from Roman times (Larsson and Lagerås 2015), these examples seem to be the earliest evidence from Iberia (Table 2).

Conclusions

Arable farming was a key element of the Roman and medieval economies and cereals were the main foodstuff in the 1st millennium ce. Various wheat species, both hulled and naked, barley and millets (Setaria italica and Panicum miliaceum, Italian and common millet) were widely cultivated across Iberia. Over the past few years there has been growing interest in the role of plants in the Roman and medieval periods and the body of data has grown accordingly. The application of systematic strategies for plant recovery is giving its first results, revealing that a new cereal, rye, became established in Iberia during the Roman period, while the Islamic period saw the arrival of two new species, Pennisetum glaucum (pearl millet) and Oryza sativa (rice). While rice was amongst the crops mentioned in the list of Islamic introductions, pearl millet is a completely new find. In fact, this is the first find of this species in Europe and North Africa.

In addition to the cereals, pulses were also widely grown. No evidence of new arrivals has been detected so far, but the variety of legumes identified is high, including broad beans, lentils, peas, grass pea, vetches and chickpeas. Among the fruits, peach and black mulberry were introduced in the Roman period while apricot, quince, medlar and citrus appear for the first time in Islamic sites in Iberia, but most of the fruit taxa mentioned by Watson (1974, 1981, 1983) are still absent. Garden plants were certainly much more numerous than the small number in the Iberian archaeobotanical dataset. This group is greatly biased by preservation, but the few waterlogged contexts have provided information about the presence of herbs, spices and vegetables. Nevertheless, comparison with other contemporary sites in Europe shows that the diversity of garden plants there is much greater than that found in Iberian sites. Finally, oil and/or fibre plants include Linum usitatissimum (flax), Camelina sativa (gold of pleasure) and Cannabis sativa (hemp). While flax is well known since prehistoric times and gold of pleasure appeared from the 1st millennium bce, hemp is only found in medieval contexts.

The above data suggest that the main cereals and legumes that had been grown over millennia in Iberia continued to be cultivated during the Roman and medieval periods. During the 1st and the beginning of the 2nd millennium ce there were several crop introductions of cereals, fruits, vegetables which were integrated into the Roman and medieval economies and became part of the normal diet (Table 2). However, these new data are only the beginning of a fascinating journey of discovery through a millennium of history. Current research projects by different Iberian archaeobotanists and a new ERC project (Medieval appetites: food plants in multicultural Iberia, 500–1100 ce-MEDAPP) directed by one of the authors (LP-CH) will certainly provide much more data and opportunities for advances in our knowledge of plant use in the medieval period.