Willow are incredibly tenacious. They will regrow from a bare 'wand' if you plant it in anything like a viable spot.
The ones you're seeing at the nursery are probably ornamental hybrids... maybe not as robust. If you don't care how 'pretty' the tree will be I wouldn't pay any money for a willow.
If you can find a person, or a wetland area, near your home that has willow growing, I'm sure you could harvest dozens of viable cuttings at no cost. I have hundreds that I'd love to get rid of... they are a bit of a weed here.
Willow whips are best cut when the tree is dormant, so late Fall or early Spring. But It's probably still worthwhile trying now if you can't wait.
Cut a branch or stem no smaller than 2cm in diameter, about 1.5 metres in length.
Make a diagonal cut above the last node (bud) and a diagonal cut through the bottom.
Place the whips into a
bucket of
water until it's time to plant.
Willow are naturally super high in rooting hormone, so save the water afterward for other rooting projects.
Use a 'dibble' (a long metal bar or rod) to make a hole about 60cm deep, top up with the rooting water and pack the base end of a whip into the hole.
make sure the nodes are pointing upward before soaking or planting.
That's it! I've gotten 80 to 100% survival rate with this method, and the losses were mostly due to
voles girding the whips over Winter. (Use a jug cut to fit around the base if you want to avoid this.)
If the area is pure clay or pure sand you may need to bring in some organic matter. Willow tend to like wet, slightly acidic conditions. Perfect for your grey (and black) water area!
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