There is no doubt that the method most used for irrigation of the terraces and balconies is watering can. It is an indispensable accessory in any home since it is very practical for watering pots and planters.
Although watering cans usually have a showerhead on the end to hand water well, I advise to remove water directly on the ground without the leaves get wet. The water on the leaves is an ideal breeding ground for fungi cultivation, so unless your plants are free of dust and want to wash the face, it is always best to irrigate on the pot. Also in this way you will save water, because sometimes the showerhead adds more water outside than inside !.
Many experts in the field are advised to spray the leaves with water to increase the humidity, mainly for indoor plants. That's fine if the plants originate in moist habitats, such as ferns, and if the water quality is extra, basically if it is a bottled water with little salt or when mains water is of good quality, which is not always given. in the big cities.
If the mains water carries many dissolved salts, these accumulate on leaves and limit transpiration, so the plants will suffer more if you pulverizas on them if you do not.