In northeastern Germany, there has been hardly any rainfall in recent months. The country's weather service says Saxony-Anhalt received just 15 liters of rainfall per square meter — roughly a quarter of the average. Across Germany, there were just 50 liters of rainfall per square meter, half of the usual amount. Mecklenburg-West Pomerania received more sunshine than any other German state.

The little rain that fell came down very unevenly across Germany. In May, the country's weather service warned of potential forest fires in parts of Lower Saxony. Meanwhile in southwestern Germany, some towns faced torrential rains that flooded cellars and roads, such as here in Fischbach, Rhineland-Palatinate.

The danger of forest fires is extremely high right now throughout the country. The state of Brandenburg faces the biggest threat. In recent weeks, authorities have been forced to put out more than 100 fires. Recently, 100 hectares of forest and wheat crops burned to the ground in the Oder-Spree region. Brandenburg authorities reported that 90 percent of fires are inadvertently caused by humans.

It took 40 firefighters 13 hours to extinguish the flames sweeping through Brandenburg's Oder-Spree region. A fire in Rostock, meanwhile, was not caused by humans — but by a bird. Police say the animal caused an electricity cable to short circuit, which then set a nearby field ablaze.

Saxony-Anhalt's firefighters, meanwhile, are so busy they needed to get creative to find new sources of water. So they headed to a nearby pool to refill their tanks. The dryness, meanwhile, not only makes fires more likely but also poses a major threat to farmers.

The unusually dry weather has forced many farmers to harvest their crops early. The German Farmers' Association has stated that even April was too warm and dry. The following months meant wheat crops ripened much faster than expected, though insufficient rain has produced a low yield. Sudden torrential rainfall, meanwhile, made matters worse by destroying parts of the crops.

Potatoes, sugar cane and corn are usually harvested in autumn. They require much more water than wheat and rapeseed. So due to the unusually dry weather, Germany's corn plants are in bad shape. The German Farmers' Association president, Joachim Rukwied, is pessimistic and fears crop failures could jeopardize the livelihoods of many farmers.

There are two kind of drought: "Drought in a meteorological sense refers to a drop in rainfall within one month below the long-term average," says Stephan Tober of the Helmholtz Center for Environmental Research. This causes a drought in the agricultural sense, meaning that there is too little water in the ground. That's a problem for wheat and meadows on the banks of river Elbe here in Dresden.

"Extreme dry spells can cause long-term damage to trees and recovery takes a long time," says Ingolf Kühn of the Helmholtz Center for Environmental Research. Vegetation has a memory, so to speak, and may adapt if there are several consecutive years with little rainfall. Some German cities have now called on residents to help out in watering trees, so that some day, cacti will not replace trees.

The Rhine River and its tributaries have lowered to dangerous levels, leading to restrictions in shipping. The Mannheim office of the federal Waterway and Shipping Department confirmed that, until conditions change, ships in the upper Rhine can only be loaded with 1500 tons of cargo, down from their usual weight of 3000 or more.

The challenge of feeding a planet that’s set to have 3 billion more people on it by 2050 - made even more acute by climate change as some parts of the planet become wetter, while others drier - means the pressure is on to find ways to feed the planet. So farming has to become more productive – and new areas to grow, especially in dry climates, must be found. One potential solution: hydroponics.

Farming with little space and producing higher crop yields: hydroponics fits the bill. Though it may sound like something out of Star Trek, it's actually been around since the Aztecs – they built floating farms around the city of Tenochtitlan. Hydroponics essentially means growing plants without soil, and instead using a nutrient-rich solution to supply them with water and minerals.

With hydroponics, plants – usually supported by soil – are propped up artificially instead, and a nutrient solution is applied to the suspended roots using a number of different methods, including spraying them with a solution mist. Together with artificial lights, heaters and other equipment, the nutrient solutions help plants develop faster, produce larger yields and grow all year round.

Hydroponics can recycle water, meaning it could use as little as 10 percent of the water a conventional farm uses – making it an option in arid environments. And the closed system means nutrients don't escape, cutting fertilizer down to as much as a quarter of what a conventional farm would use. Also, almost no pesticide is needed, since soil pests aren't an issue for plants grown without soil.

When growing sideways isn't an option, try going upwards: hydroponic growing trays can be piled on top of one another, and plants can be grown more closely next to each than in the soil, making it very efficient in terms of space. As for what kind of space they can grow in, the sky is the limit: with no need for scarce farmland, one possibility could be to have hydroponic farms in skyscrapers.

Running a hydroponic farm can be complex, energy-intensive and expensive. Plants require many essential nutrients, and the farm needs a large amount of equipment. Heat and light, supplied for free by the sun in conventional farms, have to be provided artifically and paid for. And power failures could mean whole crops are destroyed if they go too long without water and light.

Hydroponics can theoretically be used to grow any crop, although the technique lends itself best to plants such as cucumbers, salad greens, tomatoes, peppers and herbs. Given its long history, hydroponics still isn't widely used. But that looks set to change: the global hydroponic farming industry was estimated to be worth $21.2 billion in 2016. That's forecast to grow by 7 per cent each year.