Spain and Portugal share a peninsula that is mostly a high, arid plateau. Portugal’s western coast receives most of the rain. The capital cities of Muslim Andalusia were clustered on the arid plateau; Cordoba gets about 7 inches of rain annually, compared to 28 inches for Lisbon and much higher rainfalls for other Portuguese towns. Northern Spain gets snow, as well; the Christian kingdoms and the city of Barcelona were blessed with rain averages in the range of 40 to 60 inches. Toledo and Madrid? about 15 inches. (documentation for rainfall in our time linked here)
Farming technology was limited before the Muslim period. The new rulers based in Damascus could import water engineers who were used to dealing with scarcity. They also imported new plants that were well-adapted to the climate.
Portugal’s much higher rainfall made it the obvious place to grow tropical plants, so they planted groves of oranges, lemons and limes. These words are from Arabic, though “lemon” in Arabic was probably borrowed from Chinese “limung.” “Orange” came from a Persian root, naranja, via Arabic. Portugal became the tropical-fruit garden of Europe, exporting apricots, plums, and citrus fruits. “Apricot” too is from Arabic, though curiously its original source is a Latin word that meant “early ripening.” English received these fruit names from Spanish and Portuguese importers; apricot trees were able to grow farther north, in the south of England, but the citrus remained a southern export.
Abd al-Rahman particularly missed the date palms of Damascus. He may not have had to send messengers far to find date palm seeds; perhaps they went to Tunis or Carthage. Palm trees were planted in all of the Arab-dominated places; dates became an exported fruit of the arid Spanish plateau.
Spain’s landscape grew much greener under Umayyad rule. Many of the Arabic words that came into Spanish are about irrigation technology. Syrian and Egyptian engineers created a system of canals in Spain to make the most of the water they had. In the ancient world, they had long since created water-lifting mechanisms, but these were new to Spain. The main canal brought water into a place central to various farms, and water-lifting mechanisms poured water into farmers’ personal canals. Spanish water use became sophisticated, including timed canal-gates that opened and closed to permit each farmer a fair share. Spanish words for all of these things came directly from Arabic.
Several other new crops came from the Middle East. “Spinach” is an Arabic word; all of the chard plants, those dark green bitter leaves, were from the East. “Artichoke” comes from Arabic al-kharshoof, via Spanish. They also imported melons, though the word “melon” is not Arabic. “Sandia” is the Spanish for “watermelon,” an Arabic word that just didn’t make it into English. They began to plant rice in Spain, too.
Many of these crops moved out of Andalusia and into the rest of the Mediterranean world. Italy, in particular, had a record of taking whatever it received from Spain and turning it into an industry. Rice only became common in Europe when Italy took over its cultivation. During the Middle Ages, rice was an exotic food that the wealthy used as sustenance for sick people.
A number of herbs came from Al-Andalus: tarragon, carraway and carob are all Arabic words. The Arabic word for yellow gave us both saffron and safflower; saffron, an Arabic import, was soon grown all over Europe. Most importantly, sugar cultivation, learned from Muslim India, came to Spain and Portugal. It was named in Arabic “al-sukkar.” The word had already come into English but the product was very uncommon until the Portuguese became to grow it. Arab rulers had a definite sweet tooth and set up sugar refineries on some of the islands in the Mediterranean. Our word “candy” comes straight from Arabic. Two other sweets, syrup and sherbet/sorbet, come from Arabic “sharab.”