These days everybody, it seems, is opening an indoor farm! The US company, AeroFarms, is the latest enterprise to hit the news with their soon-to-be biggest indoor vertical farm in the world. As with other iterations of the indoor farm, the idea behind it is to provide more nutritious fresh produce to the local population in a more environmentally-friendly way. It is well-established that as fresh produce sits after harvest, even when refrigerated, the nutritional content begins to degrade, so having to extensively transport produce from distant traditional farms is generally detrimental. In addition, indoor farms do not have to use fertiliser (in the traditional sense), nor do they need any pesticides as the plants are grown in aseptic conditions where pests are kept at bay simply by the plants being isolated indoors. One unusual feature of the AeroFarms set-up is the use of a technique known as aeroponics in place of the more commonly-used hydroponics technologies. So what's the difference? Aeroponics, as the name suggests, delivers water and nutrients to the plants by creating a mist in the air space around the plant roots. This is different from hydroponics which delivers the same feed as a watery solution that bathes the roots. Is aeroponics better than hydroponics? It is not clear. One thing for sure is that it is more difficult (and expensive!) to create an aeroponic set-up than to build a hydroponic system, so it probably won't be the preferred system used by us amateur indoor gardeners just yet.