Over all, willows are fast growers and thus have very weak wood. This means with every storm they are going to be breaking in the wind with from a few twigs to major branches breaking off. They are not, on the whole, long lived. With the exception of a few wonderful examples, they are not going to be in your garden for more than 30 years. This is the bad news. Even given all the perfect places, perfect ground and soil, they are not going to be there forever in your garden.
Salix love rich soil. They love to live in the rich soil on the sides of rivers and streams gathering all the rich nutrients from the soil washed down with the water. They will thrive in soil with lots of compost and love to be fed. The down side is, this means they will grow faster and thus be more brittle for the wind to break. If the soil is not rich to some extent, they will not thrive and, if they live, they will be stunted and never look like a healthy plant.
This is simple. We all know that willows love the water but what about dry areas? I had never thought about willows growing in dry areas until I took a trip to New Mexico and saw this tree growing in the desert. So, being me, I asked and was told they are very short lived and only grow where you can find water close to the soil line. Thus, even in the desert, they are living in a water zone and will die off when the water disappears. There are some wonderful huge trees grown in gardens in arid areas that are watered by faithful gardeners. So can they go without water? Sure they can. They will stay there and they will live for a while but they will have die-back and even death if they go without water for too long.
So why grow them?
Why grow this tree that is so short lived and needs water in a world where there is less and less water? Why plant a tree that will be gone in twenty to thirty years with some exceptions? Simple, really. It is the look the willow gives and the things that can be made from the branches that brings people back to planting this tree in their yards and gardens. Is this a tree I would plant? Not in my garden, but I stand in awe of a well grown willow spreading it's branches over a pond. The romance is still there and if I ever owned a large pond I would be tempted to plant one - just for the few years it would give me that look that I long for.
Thank you to htop for this image.