lack of water is the big killer with hanging baskets, water gel crystals help a lot. a cup full for a 20″ basket dont scrimp , mixed through the compost will hold a lot of water. i always use moss and use an old towel to line mine put the moss in then the towel cut to fit then layer with compost mixed with gel, then start adding plants top off with compost and soak. i have a water butt i take off the lid and lower the basket in about an inch blow the rim dont submerge the whole thing or yo will lose compost. its better than soaking with a watering can as a lot of that just runs off if its very dry. the bigger baskets may get too heavy as the plants grow. but if you have a large bucket that the basket can fit into ou can fill that with water and sit the basket in it that way it takes the water up from below. you can water with a can at the same time to reduce the waiting lol.