I am on the hunt for what to plant in my front doorside garden, which is a pie shaped, south facing sun trap. It is not a huge area, roughly 10" wide at the widest part of the pie, and about the same back to the middle of the pie arc to the back corner. I considered a Japanese Umbrella Pine, so beautiful, but am concerned at how fast it may overgrow the space. I would prefer something columnar, and that would top out at about 15'. And which is realistically available for purchase locally! Open to suggestions! many thanks, all for your help.
A plant that I have 3 of, Golden Irish Yew, might work. In my experience they are bullet-proof and nicely slow growing. The 2 oldest which are about 12 years old are about 15-18" in diameter without any shearing at all. The height is about 10' with only being trimmed twice. I do not give any supplemental water to my garden except for newly planted plants to get them established and the Yews look as good as the day I planted them. They are in full sun and have easily withstood the very hot summers and a few quite cold winters without any issue. Just make sure you get the 'fastigiate' (upright) variety rather than the normal Irish Yew. I purchased mine from Art's Nursery in Surrey and they list them on their website currently. taxus-baccata-fastigiata-aurea
A heat pocket should be seen as a special spot, to be used for something that needs it. Something comparatively unusual this far north. Like a pineapple guava, a pittosporum or a pomegranate. With the columnar requirement shaving the range of choice way down. And likely to produce a stiffly formal, out of context effect. Unless you have the architecture for it, have already made a corresponding formal garden. Also, no woody plants top out - even the tallest redwoods grow taller every year.
The yew is a top contender...I planted two in a bed close by to accentuate wall space on either side of a big window. And yews are affordable! Yes the effect is a bit formal. My other option is a standard form of something evergreen ie. Ceanothus or Ligustrum (Sweet Privet).
You might try and source a dwarf umbrella pine. Sciadopitys verticillata ‘Richie's Cushion’ in particular comes to mind, and has a yellow/gold flush to the new growth. They are all a bit chunky/bushy though, more pyramidal than columnar, and might be too wide for space regardless.
