Willow Whips are they good to be at fence for privacy?

Ectophile

4m is extraordinarily tall for a willow whip.  Maybe they have been specially grown for weaving into living willow fences.  That's something you can do with thin green willow. Maybe plant one half at 45 degrees leaning one way, and the others at 45 degrees the other way.  Weave them together to make a sturdy lattice.

But given how fast willow can grow, I'm not sure there's much need for anything over 2m.

sujsuj

I cut down a Leylandii row that was about 9–10 metres tall. Because of the Leylandii, I couldn’t put a fence next to the neighbouring property. Now that the Leylandii is gone, the fence is in place, but I’ve realised how foolish it was to remove the trees—the neighbourhood now feels like an open field. The neighbour’s roof was never visible when the Leylandii was there.

I want to restore that privacy over the next 2–3 years, but I still can’t visualise how 4-metre plants that I put in this year will look in that time. Leylandii at that height cost around £100 per tree, and I haven’t been able to find a cheaper alternative.

WIAWSNB

Surely you don't miss the leylandii? A 'hedge' of them, in particular, is usually a very unattractive thing, and a 'mare to contain.
There must be some properly attractive medium sized trees you can plant, but keeping them nicely apart so they are individual trees, providing dappled shade and screening, rather than a barrier? 

molerat

A lot of tree varieties in a garden setting are not "low maintenance", in fact they are the exact opposite.  The willows, hazels and eucalyptus we have had needed about 6ft taking off the top every couple of years and leave it too long between maintenance and you are into serious chainsaw territory. As we are getting older it became a bit much getting up there on the ladder so had a complete chainsaw cull a couple of years ago.

Eldi_Dos

@sujsuj

Monty Don has a series on just now about Rhineland Gardens, in episode 1 there was a feature about ' green walls', have a look at that for inspiration. A couple of secure stanchions with wires between them at the right height could provide a framework for climbing plants to soon get to that height and provide screening.

Not sure how DIY fitting stanchions of that height is though.

Section62

Eldi_Dos said:

Monty Don has a series on just now about Rhineland Gardens, in episode 1 there was a feature about ' green walls', have a look at that for inspiration. A couple of secure stanchions with wires between them at the right height could provide a framework for climbing plants to soon get to that height and provide screening.

Not sure how DIY fitting stanchions of that height is though.

Do-able (with help), but the planners are likely to deem it not permitted development and require an application for planning consent.

Eldi_Dos

Section62 said:

Eldi_Dos said:

Monty Don has a series on just now about Rhineland Gardens, in episode 1 there was a feature about ' green walls', have a look at that for inspiration. A couple of secure stanchions with wires between them at the right height could provide a framework for climbing plants to soon get to that height and provide screening.

Not sure how DIY fitting stanchions of that height is though.

Do-able (with help), but the planners are likely to deem it not permitted development and require an application for planning consent.

Even if you told them you where reviving the lost local custom of Hop Growing?

Planners might even be members of Camra.

Section62

Eldi_Dos said:

Section62 said:

Eldi_Dos said:

Monty Don has a series on just now about Rhineland Gardens, in episode 1 there was a feature about ' green walls', have a look at that for inspiration. A couple of secure stanchions with wires between them at the right height could provide a framework for climbing plants to soon get to that height and provide screening.

Not sure how DIY fitting stanchions of that height is though.

Do-able (with help), but the planners are likely to deem it not permitted development and require an application for planning consent.

Even if you told them you where reviving the lost local custom of Hop Growing?

Planners might even be members of Camra.

For your own use, or on a commercial basis?

Eldi_Dos

Section62 said:

Eldi_Dos said:

Section62 said:

Eldi_Dos said:

Monty Don has a series on just now about Rhineland Gardens, in episode 1 there was a feature about ' green walls', have a look at that for inspiration. A couple of secure stanchions with wires between them at the right height could provide a framework for climbing plants to soon get to that height and provide screening.

Not sure how DIY fitting stanchions of that height is though.

Do-able (with help), but the planners are likely to deem it not permitted development and require an application for planning consent.

Even if you told them you where reviving the lost local custom of Hop Growing?

Planners might even be members of Camra.

For your own use, or on a commercial basis?

Jesting apart I do not know if you have ever been to Kent when it is time to harvest the hops.
Some of the local pubs have garlands of them festooned around the bar and what a lovely smell they have.
If you have never been at that time of year its worth a visit.

Section62

Eldi_Dos said:

Section62 said:

Eldi_Dos said:

Section62 said:

Eldi_Dos said:

Monty Don has a series on just now about Rhineland Gardens, in episode 1 there was a feature about ' green walls', have a look at that for inspiration. A couple of secure stanchions with wires between them at the right height could provide a framework for climbing plants to soon get to that height and provide screening.

Not sure how DIY fitting stanchions of that height is though.

Do-able (with help), but the planners are likely to deem it not permitted development and require an application for planning consent.

Even if you told them you where reviving the lost local custom of Hop Growing?

Planners might even be members of Camra.

For your own use, or on a commercial basis?

Jesting apart I do not know if you have ever been to Kent when it is time to harvest the hops.
Some of the local pubs have garlands of them festooned around the bar and what a lovely smell they have.
If you have never been at that time of year its worth a visit.

Yes, I had several friends in Kent so spent a fair bit of time there in my student days.  Coming from a rural area which didn't grow hops it was interesting to see them growing and being harvested.  Also on the family history side, seeing relatives from London doing the hop harvest 'holiday' in Kent.