The best verbena!

I have grown Verbena bonariensis for at least 10 years, if not more. Mind you, I only planted it once -- grown from seed -- but it has been a regular volunteer in my garden ever since. A welcome one at that!

Still, this is not typically a focal plant for me, more like a filler. Until this year that is, when a volunteer showed up in a planter on the deck and has shown me what a magnificent plant this can be!

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This is what Verbena bonariensis usually looks like in my garden:

A tall, narrow plant that needs to be held up by other plants or stakes. Admittedly this one is not growing in full sun so probably is a bit more lanky than it would be, but I have others growing in more sun that look the same.

This deck specimen though...

...well, it's fantastic!  Not that it gets more sun than the others do -- it probably only gets 3-4 hours of direct sunlight. For some reason though, this one branched out at the base and everywhere else, to become a marvel!

So many branches! So many blooms!

So much to like about this one!

Any ideas what I might have done right with this plant? Is it just chance? Is it perhaps the soil type, looser potting mix as opposed to the amended clay of the in-ground plants? Is it maybe because there's a clover growing in the same pot, and is providing more nitrogen?

Whatever is going on here, I hope I can repeat it next year!

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