Remember that amazing Painted Lady invasion of a couple of years ago? Millions (no exaggeration) were thought to have arrived in this country after breeding in enormous numbers in the Atlas mountains.

I've hardly seen one this year, which is very normal for a species that goes from boom to bust and back again. But I did see a smattering in Norfolk when I was there a couple of weeks ago.

And they included this one, nectaring on Erysimum Bowles Mauve at the wonderful West Acre Gardens near Swaffham.

The Erysimums are the wallflowers, which these days tend to include the cultivars of what was formerly known as Cheiranthus cheiri, the familiar sunshine-coloured bedding wallflowers.

But Bowles Mauve with its lilac flowers is a hybrid Erysimum, and was first brought to my attention by an elderly gentleman in Butterfly Conservation as being especially good for butterflies.

He gave me some cuttings in about 2005, and I've taken cuttings off his cuttings every year since. And on they go, year after year, each new plant just as vigorous as its parent was, flowering from about April to October. Wonderful!

And while it doesn't pack the butterflies in like a buddleia, I think it is still a great plant for the wildlife-friendly garden.